{"id":56813,"date":"2026-09-11T08:27:57","date_gmt":"2026-09-11T08:27:57","guid":{"rendered":"https:\/\/zobai.com\/?p=56813"},"modified":"2026-10-27T04:22:36","modified_gmt":"2026-10-27T04:22:36","slug":"pilot-operated-safety-valve-seat-tightness-near-set-pressure","status":"publish","type":"post","link":"https:\/\/zobai.com\/ar\/blog\/pilot-operated-safety-valve-seat-tightness-near-set-pressure\/","title":{"rendered":"\u0625\u062d\u0643\u0627\u0645 \u0645\u0642\u0639\u062f \u0635\u0645\u0627\u0645 \u0627\u0644\u0623\u0645\u0627\u0646 \u0627\u0644\u0630\u064a \u064a\u0639\u0645\u0644 \u0628\u0627\u0644\u0628\u0627\u064a\u0644\u0648\u062a \u0642\u0631\u0628 \u0636\u063a\u0637 \u0627\u0644\u0636\u0628\u0637"},"content":{"rendered":"<style>\n.zobai-seat-tightness-article { max-width: 100%; }\n.zobai-seat-tightness-article .zobai-table-wrap { width: 100%; max-width: 100%; overflow-x: auto; -webkit-overflow-scrolling: touch; margin: 1.25rem 0; }\n.zobai-seat-tightness-article .zobai-table-wrap table { width: 100%; min-width: 680px; border-collapse: collapse; }\n.zobai-seat-tightness-article .zobai-table-wrap th, .zobai-seat-tightness-article .zobai-table-wrap td { padding: 0.75rem; vertical-align: top; text-align: left; }\n.zobai-seat-tightness-article a { overflow-wrap: anywhere; }\n.zobai-seat-tightness-article .zobai-engineering-note { margin: 1.5rem 0; padding: 1rem 1.25rem; border-left: 3px solid currentColor; }\n.zobai-seat-tightness-article .zobai-cta { margin-top: 2rem; padding: 1.25rem; border: 1px solid currentColor; }\n.zobai-seat-tightness-article .zobai-scenario { margin: 1.5rem 0; padding: 1rem 1.25rem; border-left: 3px solid currentColor; background: rgba(127, 127, 127, 0.06); }\n.zobai-seat-tightness-article .zobai-source-note { margin: 1rem 0; padding: 0.875rem 1rem; background: rgba(127, 127, 127, 0.06); }\n.zobai-seat-tightness-article .zobai-faq-item { margin: 1.25rem 0; }\n.zobai-seat-tightness-article blockquote { margin: 1rem 0; padding-left: 1rem; border-left: 3px solid currentColor; }\n@media (max-width: 390px) {\n  .zobai-seat-tightness-article .zobai-table-wrap th, .zobai-seat-tightness-article .zobai-table-wrap td { padding: 0.625rem; }\n  .zobai-seat-tightness-article .zobai-engineering-note, .zobai-seat-tightness-article .zobai-cta, .zobai-seat-tightness-article .zobai-scenario { padding: 1rem; }\n}\n<\/style>\n<article class=\"zobai-seat-tightness-article\">\n<p>\u0641\u064a \u0628\u0639\u0636 \u0627\u0644\u062a\u0635\u0627\u0645\u064a\u0645\u060c \u064a\u0645\u0643\u0646 \u0644\u0635\u0645\u0627\u0645 \u0623\u0645\u0627\u0646 \u064a\u0639\u0645\u0644 \u0628\u0627\u0644\u0628\u0627\u064a\u0644\u0648\u062a \u0627\u0644\u062d\u0641\u0627\u0638 \u0639\u0644\u0649 \u0625\u063a\u0644\u0627\u0642 \u0645\u062d\u0643\u0645 \u0628\u064a\u0646\u0645\u0627 \u064a\u0643\u0648\u0646 \u0636\u063a\u0637 \u0627\u0644\u062a\u0634\u063a\u064a\u0644 \u0642\u0631\u064a\u0628\u064b\u0627 \u0646\u0633\u0628\u064a\u064b\u0627 \u0645\u0646 \u0636\u063a\u0637 \u0627\u0644\u0636\u0628\u0637. \u0648\u0647\u0630\u0627 \u0644\u0627 <strong>\u064a\u062d\u062f\u062f<\/strong> \u064a\u0639\u0646\u064a \u0623\u0646 \u0643\u0644 \u0635\u0645\u0627\u0645 \u064a\u0639\u0645\u0644 \u0628\u0627\u0644\u0628\u0627\u064a\u0644\u0648\u062a \u0644\u0647 \u0646\u0641\u0633 \u0647\u0627\u0645\u0634 \u0627\u0644\u062a\u0634\u063a\u064a\u0644 \u0627\u0644\u0645\u0633\u0645\u0648\u062d\u060c \u0643\u0645\u0627 \u0623\u0646 \u0646\u062a\u064a\u062c\u0629 \u0625\u062d\u0643\u0627\u0645 \u0627\u0644\u0645\u0642\u0639\u062f \u0648\u0641\u0642 API 527 \u0644\u0627 \u062a\u062d\u062f\u062f \u0628\u062d\u062f \u0630\u0627\u062a\u0647\u0627 \u0645\u062f\u0649 \u0642\u0631\u0628 \u0627\u0644\u062a\u0634\u063a\u064a\u0644 \u0627\u0644\u0637\u0628\u064a\u0639\u064a \u0644\u0646\u0638\u0627\u0645 \u0645\u0631\u0643\u0651\u0628 \u0645\u0646 \u0636\u063a\u0637 \u0627\u0644\u0636\u0628\u0637.<\/p>\n<p>\u064a\u062c\u0628 \u0623\u0646 \u062a\u0628\u0642\u0649 \u0623\u0631\u0628\u0639 \u0642\u064a\u0645 \u0645\u0646\u0641\u0635\u0644\u0629 \u0637\u0648\u0627\u0644 \u0627\u0644\u0645\u0631\u0627\u062c\u0639\u0629: <strong>\u0636\u063a\u0637 \u0627\u0644\u062a\u0634\u063a\u064a\u0644 \u0627\u0644\u0639\u0627\u062f\u064a<\/strong>, <strong>\u0636\u063a\u0637 \u0627\u0644\u0636\u0628\u0637<\/strong>, \u0627\u0644 <strong>\u0636\u063a\u0637 \u0627\u062e\u062a\u0628\u0627\u0631 \u0625\u062d\u0643\u0627\u0645 \u0627\u0644\u0645\u0642\u0639\u062f \u0648\u0645\u0639\u064a\u0627\u0631 \u0627\u0644\u0642\u0628\u0648\u0644<\/strong>, \u060c \u0648 <strong>\u0627\u0644\u062a\u0633\u0631\u0628 \u0627\u0644\u0645\u0644\u0627\u062d\u0638 \u0641\u064a \u0627\u0644\u062e\u062f\u0645\u0629 \u0627\u0644\u0641\u0639\u0644\u064a\u0629<\/strong>. \u0642\u062f \u062a\u0643\u0648\u0646 \u0645\u062a\u0631\u0627\u0628\u0637\u0629\u060c \u0644\u0643\u0646\u0647\u0627 \u062a\u062c\u064a\u0628 \u0639\u0646 \u0623\u0633\u0626\u0644\u0629 \u0647\u0646\u062f\u0633\u064a\u0629 \u0645\u062e\u062a\u0644\u0641\u0629 \u0648\u0644\u064a\u0633\u062a \u0642\u0627\u0628\u0644\u0629 \u0644\u0644\u062a\u0628\u0627\u062f\u0644.<\/p>\n<div class=\"zobai-table-wrap\" role=\"region\" aria-label=\"Operating pressure set pressure API 527 test and field leakage distinction\" tabindex=\"0\">\n<table>\n<thead>\n<tr>\n<th scope=\"col\">\u0627\u0644\u0628\u0646\u062f<\/th>\n<th scope=\"col\">\u0645\u0627 \u0627\u0644\u0630\u064a \u062a\u062e\u0628\u0631\u0643 \u0628\u0647<\/th>\n<th scope=\"col\">\u0645\u0627 \u0644\u0627 \u064a\u062d\u062f\u062f\u0647 \u0628\u062d\u062f \u0630\u0627\u062a\u0647<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>\u0636\u063a\u0637 \u0627\u0644\u062a\u0634\u063a\u064a\u0644 \u0627\u0644\u0639\u0627\u062f\u064a<\/td>\n<td>\u0636\u063a\u0637 \u0627\u0644\u0639\u0645\u0644\u064a\u0629 \u0627\u0644\u0641\u0639\u0644\u064a \u0623\u062b\u0646\u0627\u0621 \u0627\u0644\u062e\u062f\u0645\u0629 \u063a\u064a\u0631 \u0627\u0644\u062a\u0646\u0641\u064a\u0633\u064a\u0629\u060c \u0628\u0645\u0627 \u0641\u064a \u0630\u0644\u0643 \u0645\u0627 \u0625\u0630\u0627 \u0643\u0627\u0646\u062a \u0627\u0644\u0639\u0645\u0644\u064a\u0629 \u0645\u0633\u062a\u0642\u0631\u0629 \u0623\u0645 \u0645\u062a\u063a\u064a\u0631\u0629 \u062f\u0648\u0631\u064a\u064b\u0627.<\/td>\n<td>\u0646\u062a\u064a\u062c\u0629 \u0627\u062e\u062a\u0628\u0627\u0631 API 527 \u0644\u0644\u0635\u0645\u0627\u0645\u060c \u0623\u0648 \u0636\u063a\u0637 \u0627\u0644\u0636\u0628\u0637\u060c \u0623\u0648 \u0646\u0633\u0628\u0629 \u062a\u0634\u063a\u064a\u0644 \u0645\u0633\u0645\u0648\u062d \u0628\u0647\u0627 \u0639\u0627\u0644\u0645\u064a\u0629.<\/td>\n<\/tr>\n<tr>\n<td>\u0636\u063a\u0637 \u0627\u0644\u0636\u0628\u0637<\/td>\n<td>\u0636\u0628\u0637 \u0627\u0644\u0636\u063a\u0637 \u0627\u0644\u0645\u062d\u062f\u062f \u0627\u0644\u0645\u0631\u062a\u0628\u0637 \u0628\u0633\u0644\u0648\u0643 \u0627\u0644\u062a\u0634\u063a\u064a\u0644 \u0623\u0648 \u0627\u0644\u0641\u062a\u062d \u0627\u0644\u0645\u062d\u062f\u062f \u0644\u0644\u0635\u0645\u0627\u0645.<\/td>\n<td>\u0645\u0642\u062f\u0627\u0631 \u0627\u0644\u062a\u0633\u0631\u0628 \u0627\u0644\u0645\u0642\u0628\u0648\u0644 \u0641\u064a \u0627\u062e\u062a\u0628\u0627\u0631 \u0625\u062d\u0643\u0627\u0645 \u0627\u0644\u0645\u0642\u0639\u062f \u0623\u0648 \u0641\u064a \u0627\u0644\u062e\u062f\u0645\u0629 \u0627\u0644\u0645\u064a\u062f\u0627\u0646\u064a\u0629.<\/td>\n<\/tr>\n<tr>\n<td>\u0636\u063a\u0637 \u0627\u062e\u062a\u0628\u0627\u0631 \u0625\u062d\u0643\u0627\u0645 \u0627\u0644\u0645\u0642\u0639\u062f \u0648\u0641\u0642 API 527 \u0648\u0645\u0639\u0627\u064a\u064a\u0631\u0647<\/td>\n<td>\u062d\u0627\u0644\u0629 \u0627\u062e\u062a\u0628\u0627\u0631 \u0645\u062e\u0628\u0631\u064a\u0629 \u0645\u0636\u0628\u0648\u0637\u0629 \u0648\u0623\u0633\u0627\u0633 \u0642\u0628\u0648\u0644 \u0644\u0644\u062a\u0633\u0631\u0628 \u0645\u062d\u062f\u062f\u0627\u0646 \u0648\u0641\u0642 \u0627\u0644\u0645\u0639\u064a\u0627\u0631 \u0648\u0637\u0631\u064a\u0642\u0629 \u0627\u0644\u0627\u062e\u062a\u0628\u0627\u0631 \u0627\u0644\u0645\u0639\u0645\u0648\u0644 \u0628\u0647\u0645\u0627.<\/td>\n<td>The maximum normal operating pressure for every installed pilot-operated valve.<\/td>\n<\/tr>\n<tr>\n<td>Observed field leakage<\/td>\n<td>A real symptom at a known pressure, temperature, medium and operating state.<\/td>\n<td>An API 527 pass\/fail result until the leak path and the applicable controlled test basis are established.<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<p>\u064a\u062c\u0628 \u0641\u0635\u0644 \u062b\u0644\u0627\u062b\u0629 \u0623\u0633\u0626\u0644\u0629:<\/p>\n<ul>\n<li>\u0647\u0644 \u064a\u0633\u062a\u0648\u0641\u064a \u0627\u0644\u0635\u0645\u0627\u0645 <strong>\u0627\u062e\u062a\u0628\u0627\u0631 \u0625\u062d\u0643\u0627\u0645 \u0627\u0644\u0645\u0642\u0639\u062f<\/strong>?<\/li>\n<li>\u0647\u0644 <strong>\u062a\u0635\u0645\u064a\u0645 \u0627\u0644\u0635\u0645\u0627\u0645 \u0627\u0644\u0645\u062d\u062f\u062f<\/strong> \u0645\u062e\u0635\u0635 \u0644\u0644\u0639\u0645\u0644 \u0639\u0646\u062f \u0639\u0644\u0627\u0642\u0629 \u0636\u063a\u0637 \u0627\u0644\u062a\u0634\u063a\u064a\u0644 \u0627\u0644\u0641\u0639\u0644\u064a \u0625\u0644\u0649 \u0636\u063a\u0637 \u0627\u0644\u0636\u0628\u0637\u061f<\/li>\n<li>\u0647\u0644 \u064a\u0634\u064a\u0631 \u0627\u0644\u062a\u0633\u0631\u0628 \u0627\u0644\u0645\u0644\u0627\u062d\u0638 \u0623\u062b\u0646\u0627\u0621 \u0627\u0644\u062e\u062f\u0645\u0629 \u0625\u0644\u0649 \u0645\u0634\u0643\u0644\u0629 \u0641\u064a \u0627\u0644\u0635\u0645\u0627\u0645\u060c \u0623\u0648 \u0645\u0634\u0643\u0644\u0629 \u0641\u064a \u0645\u0633\u0627\u0631 \u0627\u0644\u0628\u0627\u064a\u0644\u0648\u062a\/\u0627\u0644\u062a\u062d\u0643\u0645\u060c \u0623\u0648 \u0645\u0633\u0627\u0631 \u0625\u062d\u0643\u0627\u0645 \u0622\u062e\u0631\u060c \u0623\u0648 \u0645\u0644\u0627\u062d\u0638\u0629 \u0644\u0627 \u062a\u0632\u0627\u0644 \u0628\u062d\u0627\u062c\u0629 \u0625\u0644\u0649 \u062a\u062d\u062f\u064a\u062f \u0645\u0648\u0636\u0639\u0647\u0627\u061f<\/li>\n<\/ul>\n<p>That distinction matters more than finding a single 95%, 97% or 98% number. Manufacturer percentages are product claims for identified designs; API 527 is a test standard; actual field leakage is an operating observation.<\/p>\n<p>For an engineering review, start with the actual set pressure, normal operating pressure, valve and pilot configuration, observed leakage location, service medium, operating state, and applicable test or acceptance basis.<\/p>\n<section>\n<h2>\u0645\u0627\u0630\u0627 \u064a\u0639\u0646\u064a \u201c\u0625\u062d\u0643\u0627\u0645 \u0627\u0644\u0645\u0642\u0639\u062f \u0642\u0631\u0628 \u0636\u063a\u0637 \u0627\u0644\u0636\u0628\u0637\u201d \u0641\u0639\u0644\u064a\u064b\u0627\u061f<\/h2>\n<p>\u201c\u0625\u062d\u0643\u0627\u0645 \u0627\u0644\u0645\u0642\u0639\u062f \u0642\u0631\u0628 \u0636\u063a\u0637 \u0627\u0644\u0636\u0628\u0637\u201d \u0644\u064a\u0633 \u062d\u0627\u0644\u0629 \u0647\u0646\u062f\u0633\u064a\u0629 \u0648\u0627\u062d\u062f\u0629.<\/p>\n<p><strong>\u0636\u063a\u0637 \u0627\u0644\u0636\u0628\u0637<\/strong> \u064a\u062d\u062f\u062f \u0636\u063a\u0637 \u0627\u0644\u0636\u0628\u0637 \u0627\u0644\u0645\u0631\u062a\u0628\u0637 \u0628\u0633\u0644\u0648\u0643 \u0627\u0644\u0641\u062a\u062d \u0623\u0648 \u0627\u0644\u062a\u0634\u063a\u064a\u0644 \u0627\u0644\u0645\u062d\u062f\u062f \u0644\u0644\u0635\u0645\u0627\u0645. <strong>\u0636\u063a\u0637 \u0627\u0644\u062a\u0634\u063a\u064a\u0644 \u0627\u0644\u0639\u0627\u062f\u064a<\/strong> \u0647\u0648 \u0636\u063a\u0637 \u0627\u0644\u0639\u0645\u0644\u064a\u0629 \u0623\u062b\u0646\u0627\u0621 \u0627\u0644\u062a\u0634\u063a\u064a\u0644. A <strong>\u0636\u063a\u0637 \u0627\u062e\u062a\u0628\u0627\u0631 \u0625\u062d\u0643\u0627\u0645 \u0627\u0644\u0645\u0642\u0639\u062f<\/strong> is the controlled inlet pressure used when leakage is evaluated under a specified test procedure. The <strong>acceptance criterion<\/strong> is the permitted leakage under that procedure; it is not a synonym for normal process leakage.<\/p>\n<p>Those pressures may be related, but they answer different questions. The current API publications catalog lists API Standard 527, Fifth Edition (2020), as <em>\u0625\u062d\u0643\u0627\u0645 \u0645\u0642\u0639\u062f \u0635\u0645\u0627\u0645\u0627\u062a \u062a\u062e\u0641\u064a\u0641 \u0627\u0644\u0636\u063a\u0637<\/em> and describes it as covering conventional, bellows and pilot-operated designs. It also states that the test medium is tied to the medium used to determine set pressure. <a href=\"https:\/\/www.api.org\/-\/media\/files\/publications\/2025-catalog\/06_refining_2025.pdf\" target=\"_blank\" rel=\"noopener noreferrer nofollow\">API 2025 refining publications catalog<\/a>.<\/p>\n<p>\u0644\u0627 \u064a\u062b\u0628\u062a \u0646\u062c\u0627\u062d \u0627\u062e\u062a\u0628\u0627\u0631 \u0627\u0644\u0625\u062d\u0643\u0627\u0645 \u0639\u0644\u0649 \u0627\u0644\u0645\u0646\u0635\u0629\u060c \u0628\u062d\u062f \u0630\u0627\u062a\u0647\u060c \u0627\u0644\u062d\u062f \u0627\u0644\u0623\u0642\u0635\u0649 \u0644\u0636\u063a\u0637 \u0627\u0644\u062a\u0634\u063a\u064a\u0644 \u0627\u0644\u0637\u0628\u064a\u0639\u064a \u0644\u0644\u0646\u0638\u0627\u0645 \u0627\u0644\u0645\u0631\u0643\u0628. \u0648\u0628\u0627\u0644\u0645\u062b\u0644\u060c \u0641\u0625\u0646 \u0628\u064a\u0627\u0646 \u0627\u0644\u0645\u0635\u0646\u0639 \u0628\u0623\u0646 \u0635\u0645\u0627\u0645\u064b\u0627 \u0645\u0639\u064a\u0646\u064b\u0627 \u064a\u0639\u0645\u0644 \u0628\u0627\u0644\u0628\u0627\u064a\u0644\u0648\u062a \u064a\u0645\u0643\u0646\u0647 \u0627\u0644\u0639\u0645\u0644 \u0642\u0631\u064a\u0628\u064b\u0627 \u0645\u0646 \u0636\u063a\u0637 \u0627\u0644\u0636\u0628\u0637 \u0644\u0627 \u064a\u062d\u062f\u062f \u062a\u0644\u0642\u0627\u0626\u064a\u064b\u0627 \u0645\u0639\u0627\u064a\u064a\u0631 \u0627\u0644\u0642\u0628\u0648\u0644 \u0644\u0627\u062e\u062a\u0628\u0627\u0631 API 527.<\/p>\n<h3>\u0627\u062e\u062a\u0628\u0627\u0631 \u0625\u062d\u0643\u0627\u0645 \u0627\u0644\u0645\u0642\u0639\u062f \u0648\u0627\u0644\u062a\u0634\u063a\u064a\u0644 \u0627\u0644\u0645\u0631\u0643\u0628 \u0645\u0633\u0623\u0644\u062a\u0627\u0646 \u0645\u062e\u062a\u0644\u0641\u062a\u0627\u0646<\/h3>\n<p>\u064a\u0633\u0623\u0644 \u0627\u062e\u062a\u0628\u0627\u0631 \u0625\u062d\u0643\u0627\u0645 \u0627\u0644\u0645\u0642\u0639\u062f:<\/p>\n<blockquote>\n<p>Does leakage satisfy the applicable acceptance basis under the defined test pressure, test medium, seat type, valve configuration and measurement method?<\/p>\n<\/blockquote>\n<p>\u062a\u0633\u0623\u0644 \u0645\u0631\u0627\u062c\u0639\u0629 \u0627\u0644\u062a\u0634\u063a\u064a\u0644 \u0627\u0644\u0645\u0631\u0643\u0628:<\/p>\n<blockquote>\n<p>Is the actual operating condition within the documented application and operating basis of this valve configuration, and is any observed leakage coming from the path being evaluated?<\/p>\n<\/blockquote>\n<p>The second question requires more than a leakage test report. The engineer also needs the valve design, normal operating pressure, set pressure, pilot configuration, pressure history, service medium, downstream condition and the manufacturer&#8217;s documented operating envelope.<\/p>\n<div class=\"zobai-source-note\">\n<p><strong>Test-basis boundary:<\/strong> do not convert a familiar API 527 test point into a universal operating-pressure rule. The exact current test pressure and allowable leakage must come from the controlled edition of API 527 or an OEM procedure that explicitly implements the applicable criteria. A field pressure ratio is not a substitute for that test basis.<\/p>\n<\/div>\n<h3>\u062d\u062f\u062f \u0623\u0648\u0644\u0627\u064b \u0645\u0633\u0627\u0631 \u0627\u0644\u062a\u0633\u0631\u0628 \u0627\u0644\u0630\u064a \u062a\u062a\u0645 \u0645\u0646\u0627\u0642\u0634\u062a\u0647<\/h3>\n<p>\u201cValve leakage\u201d is too broad for a useful diagnosis. A pilot-operated valve has more than one possible path that can be mistaken for main-seat leakage.<\/p>\n<div class=\"zobai-table-wrap\" role=\"region\" aria-label=\"\u062c\u062f\u0648\u0644 \u0645\u0644\u0627\u062d\u0638\u0629 \u0627\u0644\u062a\u0633\u0631\u0628 \u0648\u062a\u0641\u0633\u064a\u0631\u0647\" tabindex=\"0\">\n<table>\n<thead>\n<tr>\n<th scope=\"col\">\u0627\u0644\u0645\u0644\u0627\u062d\u0638\u0629<\/th>\n<th scope=\"col\">\u0645\u0627 \u0642\u062f \u064a\u0634\u064a\u0631 \u0625\u0644\u064a\u0647<\/th>\n<th scope=\"col\">\u0645\u0627 \u0627\u0644\u0630\u064a \u0644\u0627 \u064a\u062b\u0628\u062a\u0647 \u0628\u0645\u0641\u0631\u062f\u0647<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>\u0627\u0644\u062a\u062f\u0641\u0642 \u0627\u0644\u0645\u0644\u0627\u062d\u0638 \u0639\u0646\u062f \u0627\u0644\u0645\u062e\u0631\u062c \u0627\u0644\u0631\u0626\u064a\u0633\u064a<\/td>\n<td>\u062a\u062f\u0641\u0642 \u062f\u0627\u062e\u0644\u064a \u0639\u0628\u0631 \u0645\u0633\u0627\u0631 \u0625\u062d\u0643\u0627\u0645 \u0627\u0644\u0635\u0645\u0627\u0645 \u0627\u0644\u0631\u0626\u064a\u0633\u064a<\/td>\n<td>\u0623\u0646 \u0627\u0644\u0645\u0642\u0639\u062f \u0627\u0644\u0631\u0626\u064a\u0633\u064a \u0648\u062d\u062f\u0647 \u062a\u0627\u0644\u0641<\/td>\n<\/tr>\n<tr>\n<td>\u062a\u062f\u0641\u0642 \u0623\u0648 \u062a\u0633\u0631\u0628 \u0639\u0646\u062f \u0645\u0633\u0627\u0631 \u062a\u0647\u0648\u064a\u0629\/\u062a\u062d\u0643\u0645 \u0627\u0644\u0628\u0627\u064a\u0644\u0648\u062a<\/td>\n<td>\u062a\u0634\u063a\u064a\u0644 \u0627\u0644\u0628\u0627\u064a\u0644\u0648\u062a \u0623\u0648 \u062a\u0633\u0631\u0628 \u0627\u0644\u0628\u0627\u064a\u0644\u0648\u062a\/\u0627\u0644\u062a\u062d\u0643\u0645\u060c \u062d\u0633\u0628 \u0627\u0644\u062a\u0635\u0645\u064a\u0645 \u0648\u0627\u0644\u062d\u0627\u0644\u0629<\/td>\n<td>\u062a\u0633\u0631\u0628 \u0645\u0642\u0639\u062f \u0627\u0644\u0635\u0645\u0627\u0645 \u0627\u0644\u0631\u0626\u064a\u0633\u064a<\/td>\n<\/tr>\n<tr>\n<td>\u062a\u0633\u0631\u0628 \u0639\u0646\u062f \u0627\u0644\u0623\u0646\u0627\u0628\u064a\u0628 \u0623\u0648 \u0627\u0644\u0648\u0635\u0644\u0627\u062a \u0623\u0648 \u0627\u0644\u0648\u0635\u0644\u0627\u062a \u0627\u0644\u062e\u0627\u0631\u062c\u064a\u0629<\/td>\n<td>\u0645\u0634\u0643\u0644\u0629 \u0641\u064a \u0627\u0644\u0648\u0635\u0644\u0629 \u0627\u0644\u062e\u0627\u0631\u062c\u064a\u0629 \u0623\u0648 \u0627\u0644\u0625\u062d\u0643\u0627\u0645<\/td>\n<td>\u0641\u0634\u0644 \u062f\u0627\u062e\u0644\u064a \u0641\u064a \u0627\u0644\u0645\u0642\u0639\u062f \u0627\u0644\u0631\u0626\u064a\u0633\u064a<\/td>\n<\/tr>\n<tr>\n<td>\u0644\u0627 \u064a\u0645\u0643\u0646 \u062a\u062d\u062f\u064a\u062f \u0645\u0648\u0642\u0639 \u0627\u0644\u062a\u0633\u0631\u0628<\/td>\n<td>\u0645\u0639\u0644\u0648\u0645\u0627\u062a \u0627\u0644\u062a\u0634\u062e\u064a\u0635 \u063a\u064a\u0631 \u0645\u0643\u062a\u0645\u0644\u0629<\/td>\n<td>\u0623\u064a \u0639\u064a\u0628 \u0645\u062d\u062f\u062f \u0641\u064a \u0627\u0644\u0635\u0645\u0627\u0645<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<p>\u064a\u062c\u0628 \u062a\u0648\u0636\u064a\u062d \u0647\u0630\u0627 \u0627\u0644\u062a\u0645\u064a\u064a\u0632 \u0642\u0628\u0644 \u0645\u0646\u0627\u0642\u0634\u0629 \u0627\u0644\u0625\u0635\u0644\u0627\u062d \u0623\u0648 \u0627\u0644\u0631\u0641\u0636 \u0623\u0648 \u0647\u0627\u0645\u0634 \u0627\u0644\u062a\u0634\u063a\u064a\u0644.<\/p>\n<aside class=\"zobai-scenario\">\n<p><strong>\u0633\u064a\u0646\u0627\u0631\u064a\u0648 \u0647\u0646\u062f\u0633\u064a \u062a\u0648\u0636\u064a\u062d\u064a:<\/strong> a valve passes a controlled seat-tightness test after maintenance, but leakage is later reported in service as pressure rises close to set pressure. The bench result and the field observation are not automatically contradictory. The field review still has to identify the leak path, actual pressure history, pilot state, downstream condition and whether the installed operating point is inside the manufacturer&#8217;s documented range. The prevention is to record both the test basis and the actual operating condition instead of comparing only two percentage numbers.<\/p>\n<\/aside>\n<\/section>\n<section>\n<h2>\u0644\u0645\u0627\u0630\u0627 \u064a\u0645\u0643\u0646 \u0623\u0646 \u064a\u0628\u0642\u0649 \u0627\u0644\u0635\u0645\u0627\u0645 \u0627\u0644\u0630\u064a \u064a\u0639\u0645\u0644 \u0628\u0627\u0644\u0628\u0627\u064a\u0644\u0648\u062a \u0645\u062d\u0643\u0645 \u0627\u0644\u0625\u063a\u0644\u0627\u0642 \u0645\u0639 \u0627\u0642\u062a\u0631\u0627\u0628 \u0627\u0644\u0636\u063a\u0637 \u0645\u0646 \u0636\u063a\u0637 \u0627\u0644\u0636\u0628\u0637\u061f<\/h2>\n<p>\u062a\u0643\u0645\u0646 \u0627\u0644\u0625\u062c\u0627\u0628\u0629 \u0641\u064a \u062a\u0631\u062a\u064a\u0628 \u0642\u0648\u0649 \u0627\u0644\u0625\u063a\u0644\u0627\u0642 \u0641\u064a \u0627\u0644\u062a\u0635\u0645\u064a\u0645 \u0627\u0644\u0645\u062d\u062f\u062f \u0644\u0644\u0635\u0645\u0627\u0645 \u0627\u0644\u0630\u064a \u064a\u0639\u0645\u0644 \u0628\u0627\u0644\u0628\u0627\u064a\u0644\u0648\u062a.<\/p>\n<p>In a common piston-type arrangement, system pressure is routed to a dome or control chamber above the main piston. When pressure acts over a larger effective closing area than the area producing the opening force at the seat, the resulting force balance can hold the main valve closed while the pilot maintains the required dome pressure.<\/p>\n<p>For this type of architecture, increasing inlet pressure can therefore continue to contribute to net seating force rather than reducing seating force in the same way as a conventional direct spring-loaded arrangement. The actual behavior still depends on the pilot architecture, seals, sensing arrangement, main-valve geometry and manufacturer design.<\/p>\n<p>LESER explains its High Efficiency pilot-operated design using this differential-area principle and publishes near-set operating capability for identified products. The mechanism is useful for understanding why near-set tightness can be possible, but its exact pressure limits remain product-specific. <a href=\"https:\/\/www.leser.com\/-\/media\/files\/catalogue\/english\/high_efficiency_catalog_en.pdf?hash=F01B537D5CC808C8AB28A552FD6B5A97&amp;mw=570\" target=\"_blank\" rel=\"noopener noreferrer nofollow\">\u0645\u0639\u0644\u0648\u0645\u0627\u062a LESER \u0627\u0644\u0641\u0646\u064a\u0629 \u0639\u0646 POSV \u0639\u0627\u0644\u064a \u0627\u0644\u0643\u0641\u0627\u0621\u0629<\/a>.<\/p>\n<aside class=\"zobai-engineering-note\">\n<p><strong>\u0627\u0644\u062d\u062f \u0627\u0644\u0647\u0646\u062f\u0633\u064a:<\/strong> the force-balance mechanism can explain why close-to-set-pressure tightness is possible. It does not establish the allowable operating margin for an unverified valve, nor does it convert a manufacturer operating claim into an API 527 acceptance criterion.<\/p>\n<\/aside>\n<figure class=\"wp-block-image size-full zobai-figure\" data-image-slot=\"IMG-01\"><img loading=\"lazy\" src=\"https:\/\/zobai.com\/wp-content\/uploads\/2026\/09\/pilot-operated-seat-tightness-img-01.webp\" alt=\"\u0645\u062e\u0637\u0637 \u0645\u0628\u0633\u0637 \u0644\u062a\u0648\u0627\u0632\u0646 \u0627\u0644\u0642\u0648\u0649 \u0644\u0635\u0645\u0627\u0645 \u0623\u0645\u0627\u0646 \u064a\u0639\u0645\u0644 \u0628\u0627\u0644\u0628\u0627\u064a\u0644\u0648\u062a \u0645\u0646 \u0646\u0648\u0639 \u0627\u0644\u0645\u0643\u0628\u0633 \u064a\u0648\u0636\u062d \u0636\u063a\u0637 \u0627\u0644\u0645\u062f\u062e\u0644 \u0648\u0636\u063a\u0637 \u0627\u0644\u0642\u0628\u0629 \u0648\u0635\u0627\u0641\u064a \u0642\u0648\u0629 \u0627\u0644\u0625\u063a\u0644\u0627\u0642 \u0639\u0644\u0649 \u0627\u0644\u0635\u0645\u0627\u0645 \u0627\u0644\u0631\u0626\u064a\u0633\u064a.\" title=\"\u0625\u062d\u0643\u0627\u0645 \u0645\u0642\u0639\u062f \u0635\u0645\u0627\u0645 \u0623\u0645\u0627\u0646 \u064a\u0639\u0645\u0644 \u0628\u0627\u0644\u0628\u0627\u064a\u0644\u0648\u062a \u0642\u0631\u0628 \u0636\u063a\u0637 \u0627\u0644\u0636\u0628\u0637 - IMG-01\" width=\"1200\" height=\"900\" class=\"wp-image-56879\" decoding=\"async\" srcset=\"https:\/\/zobai.com\/wp-content\/uploads\/2026\/09\/pilot-operated-seat-tightness-img-01.webp 1200w, https:\/\/zobai.com\/wp-content\/uploads\/2026\/09\/pilot-operated-seat-tightness-img-01-300x225.webp 300w, https:\/\/zobai.com\/wp-content\/uploads\/2026\/09\/pilot-operated-seat-tightness-img-01-1024x768.webp 1024w, https:\/\/zobai.com\/wp-content\/uploads\/2026\/09\/pilot-operated-seat-tightness-img-01-768x576.webp 768w, https:\/\/zobai.com\/wp-content\/uploads\/2026\/09\/pilot-operated-seat-tightness-img-01-16x12.webp 16w, https:\/\/zobai.com\/wp-content\/uploads\/2026\/09\/pilot-operated-seat-tightness-img-01-400x300.webp 400w\" sizes=\"auto, (max-width: 1200px) 100vw, 1200px\" \/><figcaption>\u0645\u062e\u0637\u0637 \u0645\u0628\u0633\u0637 \u0644\u062a\u0648\u0627\u0632\u0646 \u0627\u0644\u0642\u0648\u0649 \u0644\u0635\u0645\u0627\u0645 \u0623\u0645\u0627\u0646 \u064a\u0639\u0645\u0644 \u0628\u0627\u0644\u0628\u0627\u064a\u0644\u0648\u062a \u0645\u0646 \u0646\u0648\u0639 \u0627\u0644\u0645\u0643\u0628\u0633 \u064a\u0648\u0636\u062d \u0636\u063a\u0637 \u0627\u0644\u0645\u062f\u062e\u0644 \u0648\u0636\u063a\u0637 \u0627\u0644\u0642\u0628\u0629 \u0648\u0635\u0627\u0641\u064a \u0642\u0648\u0629 \u0627\u0644\u0625\u063a\u0644\u0627\u0642 \u0639\u0644\u0649 \u0627\u0644\u0635\u0645\u0627\u0645 \u0627\u0644\u0631\u0626\u064a\u0633\u064a.<\/figcaption><\/figure>\n<p>\u0644\u0645\u0632\u064a\u062f \u0645\u0646 \u0627\u0644\u062a\u0641\u0627\u0635\u064a\u0644 \u062d\u0648\u0644 \u062a\u0633\u0644\u0633\u0644 \u0627\u0644\u062a\u0634\u063a\u064a\u0644 \u0627\u0644\u0643\u0627\u0645\u0644 \u0648\u0644\u064a\u0633 \u0641\u0642\u0637 \u0622\u0644\u064a\u0629 \u0625\u062d\u0643\u0627\u0645 \u0627\u0644\u0645\u0642\u0639\u062f\u060c \u0631\u0627\u062c\u0639 <a href=\"https:\/\/zobai.com\/ar\/blog\/how-does-a-pilot-operated-safety-valve-work\/\">\u0643\u064a\u0641 \u064a\u0639\u0645\u0644 \u0635\u0645\u0627\u0645 \u0627\u0644\u0623\u0645\u0627\u0646 \u0627\u0644\u0630\u064a \u064a\u0639\u0645\u0644 \u0628\u0627\u0644\u0628\u0627\u064a\u0644\u0648\u062a<\/a>.<\/p>\n<h3>\u0639\u0645\u0644 \u0627\u0644\u0628\u0627\u064a\u0644\u0648\u062a \u0648\u0641\u062a\u062d \u0627\u0644\u0635\u0645\u0627\u0645 \u0627\u0644\u0631\u0626\u064a\u0633\u064a \u0644\u064a\u0633\u0627 \u062f\u0627\u0626\u0645\u064b\u0627 \u062d\u062f\u062b\u064b\u0627 \u0648\u0627\u062d\u062f\u064b\u0627<\/h3>\n<p>Pilot-operated designs differ in how pressure is controlled as the system approaches set pressure. A pop-action pilot and a modulating pilot do not necessarily change dome pressure in the same sequence, and the presence of pilot vent flow does not by itself prove that the main valve seat is passing.<\/p>\n<p>A modulating pilot may begin changing the control pressure before the main valve reaches a fully relieving state. Other pilot arrangements can follow different sequences. The manufacturer operating description for the exact pilot must therefore be used when interpreting vent flow or pressure changes near set pressure.<\/p>\n<p>\u0644\u0647\u0630\u0627 \u0627\u0644\u0633\u0628\u0628\u060c \u0644\u0627 \u064a\u0646\u0628\u063a\u064a \u0627\u0644\u062a\u0639\u0627\u0645\u0644 \u0645\u0639 \u0646\u0634\u0627\u0637 \u0627\u0644\u0628\u0627\u064a\u0644\u0648\u062a \u0648\u062a\u062f\u0641\u0642 \u062a\u0646\u0641\u064a\u0633 \u0627\u0644\u0628\u0627\u064a\u0644\u0648\u062a \u0648\u062a\u0633\u0631\u0628 \u0645\u0642\u0639\u062f \u0627\u0644\u0635\u0645\u0627\u0645 \u0627\u0644\u0631\u0626\u064a\u0633\u064a \u0639\u0644\u0649 \u0623\u0646\u0647\u0627 \u0645\u0635\u0637\u0644\u062d\u0627\u062a \u0645\u062a\u0631\u0627\u062f\u0641\u0629.<\/p>\n<p><strong>\u0627\u0633\u062a\u062e\u062f\u0645 \u0633\u0644\u0648\u0643 \u0627\u0644\u062a\u0634\u063a\u064a\u0644 \u0627\u0644\u0645\u0648\u062b\u0642 \u0644\u062a\u0643\u0648\u064a\u0646 \u0627\u0644\u0628\u0627\u064a\u0644\u0648\u062a \u0648\u0627\u0644\u0635\u0645\u0627\u0645 \u0627\u0644\u0631\u0626\u064a\u0633\u064a \u0627\u0644\u0641\u0639\u0644\u064a\u060c \u0648\u0644\u064a\u0633 \u0627\u0641\u062a\u0631\u0627\u0636\u064b\u0627 \u0639\u0627\u0645\u064b\u0627 \u064a\u0646\u0637\u0628\u0642 \u0639\u0644\u0649 \u062c\u0645\u064a\u0639 \u0627\u0644\u0635\u0645\u0627\u0645\u0627\u062a \u0627\u0644\u062a\u064a \u062a\u0639\u0645\u0644 \u0628\u0627\u0644\u0628\u0627\u064a\u0644\u0648\u062a.<\/strong><\/p>\n<aside class=\"zobai-scenario\">\n<p><strong>\u0633\u064a\u0646\u0627\u0631\u064a\u0648 \u0647\u0646\u062f\u0633\u064a \u062a\u0648\u0636\u064a\u062d\u064a:<\/strong> gas is noticed at a pilot vent while the main outlet shows no confirmed flow. Calling that \u201cmain-seat leakage\u201d would skip the first diagnostic step. The engineer should confirm the pilot type, current pressure relative to set pressure, expected pilot vent behavior and the main-outlet condition before assigning a main-seat defect.<\/p>\n<\/aside>\n<\/section>\n<section>\n<h2>\u0647\u0644 \u064a\u064f\u0639\u062f 95% \u0623\u0648 98% \u0645\u0646 \u0636\u063a\u0637 \u0627\u0644\u0636\u0628\u0637 \u0642\u0627\u0639\u062f\u0629 \u0639\u0627\u0645\u0629 \u0644\u0625\u062d\u0643\u0627\u0645 \u0627\u0644\u0645\u0642\u0639\u062f\u061f<\/h2>\n<p><strong>\u0644\u0627. \u0625\u0646 \u0642\u064a\u0645\u0629 95% \u0623\u0648 97% \u0623\u0648 98% \u0644\u064a\u0633\u062a \u0642\u0627\u0639\u062f\u0629 \u0639\u0627\u0645\u0629 \u062a\u0646\u0637\u0628\u0642 \u0639\u0644\u0649 \u062c\u0645\u064a\u0639 \u0635\u0645\u0627\u0645\u0627\u062a \u0627\u0644\u0623\u0645\u0627\u0646 \u0627\u0644\u062a\u064a \u062a\u0639\u0645\u0644 \u0628\u0627\u0644\u0628\u0627\u064a\u0644\u0648\u062a.<\/strong><\/p>\n<p>\u064a\u0648\u0636\u062d \u0627\u0644\u062a\u0641\u0627\u0648\u062a \u0628\u064a\u0646 \u0645\u0646\u0634\u0648\u0631\u0627\u062a \u0627\u0644\u0645\u0635\u0646\u0639\u064a\u0646 \u0627\u0644\u0623\u0635\u0644\u064a\u064a\u0646 \u0633\u0628\u0628 \u0630\u0644\u0643. \u062a\u0634\u064a\u0631 \u0633\u0644\u0633\u0644\u0629 Anderson Greenwood Series 200 \u0645\u0646 Emerson \u0625\u0644\u0649 \u0625\u062d\u0643\u0627\u0645 \u0643\u0627\u0645\u0644 \u0644\u0644\u0635\u0645\u0627\u0645 \u062d\u062a\u0649 <strong>95% \u0645\u0646 \u0636\u063a\u0637 \u0627\u0644\u0636\u0628\u0637<\/strong> for that series. LESER&#8217;s current High Efficiency pilot-operated product group advertises operating pressures up to <strong>97% \u0645\u0646 \u0636\u063a\u0637 \u0627\u0644\u0636\u0628\u0637<\/strong>, while individual valve-type pages publish their own limits. Baker Hughes states main-valve and pilot-seat tightness up to <strong>98% \u0645\u0646 \u0636\u063a\u0637 \u0627\u0644\u0636\u0628\u0637<\/strong> for its Consolidated pilot-operated valves. These are manufacturer- and product-specific claims, not API 527 test-pressure definitions and not category-wide operating rules.<\/p>\n<p>\u0627\u0644\u0645\u0635\u0627\u062f\u0631: <a href=\"https:\/\/www.emerson.com\/is\/content\/emerson\/en\/final-control\/pressure-management\/prv\/general\/documents\/PRM-TDS-Series-200_400_500_700_800-Pilot-Operated-Relief-Valves-VCTDS-00543-EN.pdf\" target=\"_blank\" rel=\"noopener noreferrer nofollow\">\u0633\u0644\u0633\u0644\u0629 Emerson Anderson Greenwood 200<\/a>, <a href=\"https:\/\/www.leser.com\/en\/products\/high-efficiency-posv\/\" target=\"_blank\" rel=\"noopener noreferrer nofollow\">\u0635\u0645\u0627\u0645 \u0623\u0645\u0627\u0646 \u064a\u0639\u0645\u0644 \u0628\u0627\u0644\u0628\u0627\u064a\u0644\u0648\u062a \u0639\u0627\u0644\u064a \u0627\u0644\u0643\u0641\u0627\u0621\u0629 \u0645\u0646 LESER<\/a>, \u060c \u0648 <a href=\"https:\/\/valves.bakerhughes.com\/consolidatedpilot-operated-safety-relief-valves\" target=\"_blank\" rel=\"noopener noreferrer nofollow\">\u0635\u0645\u0627\u0645 \u062a\u0646\u0641\u064a\u0633 \u0636\u063a\u0637 \u064a\u0639\u0645\u0644 \u0628\u0627\u0644\u0628\u0627\u064a\u0644\u0648\u062a \u0645\u0646 Baker Hughes Consolidated<\/a>.<\/p>\n<div class=\"zobai-table-wrap\" role=\"region\" aria-label=\"Manufacturer near set pressure statements and what they mean\" tabindex=\"0\">\n<table>\n<thead>\n<tr>\n<th scope=\"col\">Published statement<\/th>\n<th scope=\"col\">\u0645\u0627 \u064a\u0645\u0643\u0646 \u0623\u0646 \u064a\u062f\u0639\u0645\u0647<\/th>\n<th scope=\"col\">What it cannot support<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Anderson Greenwood Series 200: total valve tightness to at least 95% of set pressure<\/td>\n<td>A product-family performance statement for that identified Series 200 design<\/td>\n<td>A universal 95% POSV rule or the API 527 test pressure<\/td>\n<\/tr>\n<tr>\n<td>LESER High Efficiency POSV group: operating pressures up to 97% of set pressure<\/td>\n<td>A manufacturer operating-envelope statement at the product-group level; exact type still requires confirmation<\/td>\n<td>A promise that every LESER POSV or every POSV from any maker operates at 97%<\/td>\n<\/tr>\n<tr>\n<td>Baker Hughes Consolidated POSRV: main-valve and pilot-seat tightness up to 98% of set pressure<\/td>\n<td>A manufacturer-specific tightness capability for the stated product family<\/td>\n<td>An API 527 acceptance criterion or an industry-wide 98% requirement<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<h3>\u0623\u0631\u0628\u0639\u0629 \u0623\u0633\u0626\u0644\u0629 \u064a\u062c\u0628 \u0637\u0631\u062d\u0647\u0627 \u0642\u0628\u0644 \u0627\u0633\u062a\u062e\u062f\u0627\u0645 \u0623\u064a \u0646\u0633\u0628\u0629 \u0645\u0626\u0648\u064a\u0629<\/h3>\n<ol>\n<li><strong>\u0645\u0646 \u064a\u0645\u0644\u0643 \u0627\u0644\u0631\u0642\u0645\u061f<\/strong> Is it the exact valve manufacturer and product family, a project specification, a controlled test procedure or another source?<\/li>\n<li><strong>\u0645\u0627\u0630\u0627 \u062a\u0635\u0641 \u0627\u0644\u0646\u0633\u0628\u0629 \u0627\u0644\u0645\u0626\u0648\u064a\u0629\u061f<\/strong> Normal operating pressure, a manufacturer&#8217;s seat-tightness capability, API 527 test pressure, pilot actuation behavior and blowdown are different parameters.<\/li>\n<li><strong>\u0645\u0627 \u0647\u0648 \u062a\u0643\u0648\u064a\u0646 \u0627\u0644\u0635\u0645\u0627\u0645 \u0627\u0644\u0630\u064a \u062a\u0646\u0637\u0628\u0642 \u0639\u0644\u064a\u0647\u061f<\/strong> Confirm the series, pilot type, main-seat design, sensing method and relevant options.<\/li>\n<li><strong>\u062a\u062d\u062a \u0623\u064a \u0638\u0631\u0641 \u062a\u0646\u0637\u0628\u0642\u061f<\/strong> A bench test, a product performance statement and an installed operating recommendation are not automatically equivalent.<\/li>\n<\/ol>\n<p>\u064a\u0645\u0646\u0639 \u0647\u0630\u0627 \u062e\u0637\u0623 \u062a\u0648\u0631\u064a\u062f \u0634\u0627\u0626\u0639\u064b\u0627: \u0627\u0644\u0639\u062b\u0648\u0631 \u0639\u0644\u0649 \u0623\u0639\u0644\u0649 \u0646\u0633\u0628\u0629 \u0645\u0626\u0648\u064a\u0629 \u0645\u0646\u0634\u0648\u0631\u0629 \u0645\u0646 \u0645\u0648\u0631\u062f \u0648\u0627\u062d\u062f \u0648\u0627\u0633\u062a\u062e\u062f\u0627\u0645\u0647\u0627 \u0644\u062a\u0642\u064a\u064a\u0645 \u0635\u0645\u0627\u0645 \u0645\u062e\u062a\u0644\u0641.<\/p>\n<h3>\u0644\u0627 \u062a\u062d\u0648\u0651\u0644 \u0642\u062f\u0631\u0629 \u0645\u0646\u062a\u062c \u0625\u0644\u0649 \u0642\u0627\u0639\u062f\u0629 \u0635\u0646\u0627\u0639\u064a\u0629<\/h3>\n<p>A statement such as \u201ctight to 98% of set pressure\u201d can be meaningful when it belongs to the exact valve family being evaluated and the stated conditions are understood.<\/p>\n<p>\u062a\u0635\u0628\u062d \u063a\u064a\u0631 \u0645\u0648\u062b\u0648\u0642\u0629 \u062a\u0642\u0646\u064a\u064b\u0627 \u0639\u0646\u062f \u0625\u0639\u0627\u062f\u0629 \u0635\u064a\u0627\u063a\u062a\u0647\u0627 \u0639\u0644\u0649 \u0627\u0644\u0646\u062d\u0648 \u0627\u0644\u062a\u0627\u0644\u064a:<\/p>\n<blockquote>\n<p>\u064a\u0645\u0643\u0646 \u0644\u062c\u0645\u064a\u0639 \u0635\u0645\u0627\u0645\u0627\u062a \u0627\u0644\u0623\u0645\u0627\u0646 \u0627\u0644\u062a\u064a \u062a\u0639\u0645\u0644 \u0628\u0627\u0644\u0628\u0627\u064a\u0644\u0648\u062a \u0623\u0646 \u062a\u0639\u0645\u0644 \u0639\u0646\u062f 98% \u0645\u0646 \u0636\u063a\u0637 \u0627\u0644\u0636\u0628\u0637 \u062f\u0648\u0646 \u062a\u0633\u0631\u0628.<\/p>\n<\/blockquote>\n<p>\u0644\u0627 \u062a\u062f\u0639\u0645 \u0627\u0644\u0623\u062f\u0644\u0629 \u0647\u0630\u0627 \u0627\u0644\u062a\u0639\u0645\u064a\u0645.<\/p>\n<aside class=\"zobai-scenario\">\n<p><strong>\u0633\u064a\u0646\u0627\u0631\u064a\u0648 \u0647\u0646\u062f\u0633\u064a \u062a\u0648\u0636\u064a\u062d\u064a:<\/strong> a procurement specification copies a near-set percentage from one manufacturer&#8217;s catalog and applies it as the acceptance threshold for a different POSV family. The number now has the wrong owner and possibly the wrong meaning. The corrective action is to separate the required plant operating margin from the seat-tightness test basis and require the proposed supplier to document both for the exact configuration.<\/p>\n<\/aside>\n<p>For ZOBAI product discussions, do not assign an unverified 95%, 97% or 98% near-set operating claim to a valve simply because another manufacturer publishes that number. Use the exact proposed model documentation and the applicable test basis.<\/p>\n<\/section>\n<section>\n<h2>\u0627\u062e\u062a\u0628\u0627\u0631 \u0625\u062d\u0643\u0627\u0645 \u0627\u0644\u0645\u0642\u0639\u062f \u0648\u0641\u0642 API 527 \u0645\u0642\u0627\u0628\u0644 \u0627\u0644\u062a\u0634\u063a\u064a\u0644 \u0627\u0644\u0641\u0639\u0644\u064a \u0642\u0631\u0628 \u0636\u063a\u0637 \u0627\u0644\u0636\u0628\u0637<\/h2>\n<p>\u0627\u0644\u0645\u0639\u064a\u0627\u0631 API 527 \u064a\u062d\u0645\u0644 \u062a\u062d\u062f\u064a\u062f\u064b\u0627 \u0627\u0644\u0639\u0646\u0648\u0627\u0646 <em>\u0625\u062d\u0643\u0627\u0645 \u0645\u0642\u0639\u062f \u0635\u0645\u0627\u0645\u0627\u062a \u062a\u062e\u0641\u064a\u0641 \u0627\u0644\u0636\u063a\u0637<\/em>. API&#8217;s current standards plan and publications catalog list Standard 527 as the <strong>fifth edition issued in 2020<\/strong>. <a href=\"https:\/\/www.api.org\/products-and-services\/standards\/standards-plan\" target=\"_blank\" rel=\"noopener noreferrer nofollow\">\u062e\u0637\u0629 \u0645\u0639\u0627\u064a\u064a\u0631 API<\/a>.<\/p>\n<p>The official API publications catalog describes API 527 as covering seat-tightness methods for metal- and soft-seated pressure-relief valves, including conventional, bellows and pilot-operated designs. It also states that maximum acceptable leakage rates are defined within the standard and that the seat-tightness test medium is tied to the medium used to determine set pressure. <a href=\"https:\/\/www.api.org\/-\/media\/files\/publications\/2025-catalog\/06_refining_2025.pdf\" target=\"_blank\" rel=\"noopener noreferrer nofollow\">API Standard 527 description in the API publications catalog<\/a>.<\/p>\n<p>The current API 527 scope is also indexed by standards distributors, including the existing reference retained here: <a href=\"https:\/\/www.intertekinform.com\/en-us\/standards\/api-std-527-2020-r2025--96977_saig_api_api_3652878\/\" target=\"_blank\" rel=\"noopener noreferrer nofollow\">\u0642\u0627\u0626\u0645\u0629 \u0646\u0637\u0627\u0642 API STD 527 \u0627\u0644\u062d\u0627\u0644\u064a<\/a>. For the actual test-pressure table, leakage limits and procedural details, the controlled API document or an approved OEM test procedure is the governing source\u2014not a secondary summary.<\/p>\n<p>\u0648\u0647\u0630\u0627 \u064a\u062c\u0639\u0644 API 527 \u0648\u062b\u064a\u0642\u0629 \u0627\u0644\u0635\u0644\u0629 \u0645\u0628\u0627\u0634\u0631\u0629 \u0628\u0647\u0630\u0627 \u0627\u0644\u0645\u0642\u0627\u0644 \u2014 \u0648\u0644\u0643\u0646 \u0641\u0642\u0637 \u0644\u0644\u0648\u0638\u064a\u0641\u0629 \u0627\u0644\u062a\u064a \u064a\u0624\u062f\u064a\u0647\u0627 \u0641\u0639\u0644\u064a\u064b\u0627.<\/p>\n<h3>\u0645\u0627 \u064a\u0645\u0643\u0646 \u0623\u0646 \u064a\u062b\u0628\u062a\u0647 \u062f\u0644\u064a\u0644 API 527<\/h3>\n<p>An applicable API 527 test can provide evidence that the valve met the relevant seat-tightness acceptance basis under the prescribed bench-test conditions. The evidence is only meaningful when the test pressure, test medium, seat type, valve configuration, stabilization\/observation method and leakage criterion are the ones required by the applicable procedure.<\/p>\n<p>For procurement and QA, that is useful because it gives the buyer and supplier a defined basis for discussing leakage acceptance. It should be recorded as test evidence, not rewritten as a normal operating-pressure recommendation.<\/p>\n<p>\u0644\u0645\u0639\u0627\u0644\u062c\u0629 \u0623\u0639\u0645\u0642 \u0644\u0644\u0627\u062e\u062a\u0628\u0627\u0631 \u0646\u0641\u0633\u0647\u060c \u0631\u0627\u062c\u0639 <a href=\"https:\/\/zobai.com\/ar\/standards\/api-527-seat-tightness-test\/\">\u062f\u0644\u064a\u0644 \u0627\u062e\u062a\u0628\u0627\u0631 \u0625\u062d\u0643\u0627\u0645 \u0627\u0644\u0645\u0642\u0639\u062f \u0648\u0641\u0642 API 527<\/a>.<\/p>\n<div class=\"zobai-table-wrap\" role=\"region\" aria-label=\"Which source answers which seat tightness question\" tabindex=\"0\">\n<table>\n<thead>\n<tr>\n<th scope=\"col\">\u0633\u0624\u0627\u0644<\/th>\n<th scope=\"col\">Primary evidence to use<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>What is the API 527 test pressure and allowable leakage for this test case?<\/td>\n<td>The controlled current edition of API 527, plus the approved test procedure implementing it<\/td>\n<\/tr>\n<tr>\n<td>How close to set pressure may this valve normally operate?<\/td>\n<td>The exact manufacturer&#8217;s operating envelope and project operating basis<\/td>\n<\/tr>\n<tr>\n<td>What behavior is expected from the pilot and main valve near set pressure?<\/td>\n<td>The OEM operating\/IOM documentation for the exact pilot-main-valve configuration<\/td>\n<\/tr>\n<tr>\n<td>Does the valve meet the required overpressure-protection code basis?<\/td>\n<td>The applicable project code and device certification\/marking evidence; ASME BPVC Section XIII is one current overpressure-protection framework<\/td>\n<\/tr>\n<tr>\n<td>What general product requirements apply to a pilot-operated safety valve under ISO?<\/td>\n<td>ISO 4126-4 for product requirements; ISO states that Part 4 is not an application standard<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<p><a href=\"https:\/\/www.asme.org\/codes-standards\/find-codes-standards\/bpvc-section-xiii-rules-for-overpressure-protection\" target=\"_blank\" rel=\"noopener noreferrer nofollow\">ASME BPVC \u0627\u0644\u0642\u0633\u0645 XIII<\/a> covers overpressure-protection rules including pressure-relief-valve design, testing, marking, capacity certification and installation. That broader code role should not be confused with API 527&#8217;s seat-tightness acceptance function.<\/p>\n<h3>\u0645\u0627 \u0644\u0627 \u064a\u062d\u062f\u062f\u0647 \u0628\u062d\u062f \u0630\u0627\u062a\u0647<\/h3>\n<p>\u0646\u062a\u064a\u062c\u0629 API 527 \u0644\u0627 <strong>\u064a\u062d\u062f\u062f<\/strong>, \u060c \u0628\u062d\u062f \u0630\u0627\u062a\u0647\u0627\u060c \u062a\u062b\u0628\u062a:<\/p>\n<ul>\n<li>\u0623\u0642\u0635\u0649 \u0636\u063a\u0637 \u062a\u0634\u063a\u064a\u0644 \u0637\u0628\u064a\u0639\u064a \u0644\u0644\u0639\u0645\u0644\u064a\u0629 \u0627\u0644\u0645\u0631\u0643\u0651\u0628\u0629\u061b;<\/li>\n<li>\u062d\u062f \u062a\u0634\u063a\u064a\u0644 \u0639\u0627\u0644\u0645\u064a \u0628\u0646\u0633\u0628\u0629 95% \u0623\u0648 97% \u0623\u0648 98%\u061b;<\/li>\n<li>\u0636\u0645\u0627\u0646 \u0639\u062f\u0645 \u0648\u062c\u0648\u062f \u062a\u0633\u0631\u0628 \u0645\u064a\u062f\u0627\u0646\u064a \u062a\u062d\u062a \u0623\u064a \u0638\u0631\u0641 \u062e\u062f\u0645\u0629\u061b;<\/li>\n<li>\u0623\u0646 \u0627\u0644\u0628\u0627\u064a\u0644\u0648\u062a \u0623\u0648 \u0627\u0644\u0627\u0633\u062a\u0634\u0639\u0627\u0631 \u0623\u0648 \u0627\u0644\u0623\u062e\u062a\u0627\u0645 \u0627\u0644\u062e\u0627\u0631\u062c\u064a\u0629 \u0623\u0648 \u0638\u0631\u0648\u0641 \u0627\u0644\u0645\u0635\u0628 \u0644\u0627 \u064a\u0645\u0643\u0646 \u0623\u0646 \u062a\u0633\u0627\u0647\u0645 \u0641\u064a \u0645\u0634\u0643\u0644\u0629 \u062a\u0633\u0631\u0628\u061b;<\/li>\n<li>\u0623\u0646 \u0643\u0644 \u0635\u0645\u0627\u0645 \u064a\u0639\u0645\u0644 \u0628\u0627\u0644\u0628\u0627\u064a\u0644\u0648\u062a \u0648\u064a\u0634\u064a\u0631 \u0625\u0644\u0649 API 527 \u0644\u0647 \u0646\u0641\u0633 \u0647\u0627\u0645\u0634 \u0627\u0644\u062a\u0634\u063a\u064a\u0644.<\/li>\n<\/ul>\n<p>ISO 4126-4 reinforces the need to separate product requirements from application decisions. ISO describes Part 4 as a product standard for pilot-operated safety valves and states that it is not an application standard; the current 2013 edition was reviewed and confirmed by ISO in 2025. <a href=\"https:\/\/www.iso.org\/standard\/50827.html\" target=\"_blank\" rel=\"noopener noreferrer nofollow\">ISO 4126-4<\/a>.<\/p>\n<aside class=\"zobai-engineering-note\">\n<p><strong>\u0627\u0644\u062a\u0641\u0633\u064a\u0631 \u0627\u0644\u0647\u0646\u062f\u0633\u064a:<\/strong> seat-tightness evidence answers a controlled test question. The allowable installed operating condition requires the applicable valve design, OEM operating envelope and project basis. Passing API 527 and operating acceptably near set pressure are related only when the applicable documentation explicitly connects them.<\/p>\n<\/aside>\n<h3>\u062a\u062c\u0646\u0628 \u062a\u062d\u0648\u064a\u0644 \u0645\u0631\u062c\u0639 \u0627\u062e\u062a\u0628\u0627\u0631 \u0625\u0644\u0649 \u0627\u062f\u0639\u0627\u0621 \u0627\u0639\u062a\u0645\u0627\u062f<\/h3>\n<p>\u0625\u0630\u0627 \u0630\u0643\u0631 \u0643\u062a\u0627\u0644\u0648\u062c \u0623\u0648 \u0645\u0633\u062a\u0646\u062f \u0627\u062e\u062a\u0628\u0627\u0631 \u0623\u0646 \u0627\u0644\u0625\u062d\u0643\u0627\u0645 \u0645\u0637\u0627\u0628\u0642 \u0644\u0640 API 527 \u0623\u0648 \u0645\u064f\u062e\u062a\u0628\u0631 \u0628\u0627\u0633\u062a\u062e\u062f\u0627\u0645\u0647\u060c \u0641\u0627\u062d\u062a\u0641\u0638 \u0628\u0647\u0630\u0627 \u0627\u0644\u0646\u0637\u0627\u0642 \u0643\u0645\u0627 \u0647\u0648.<\/p>\n<p>\u0644\u0627 \u062a\u0639\u062f \u0635\u064a\u0627\u063a\u062a\u0647 \u0636\u0645\u0646\u064a\u064b\u0627 \u0639\u0644\u0649 \u0627\u0644\u0646\u062d\u0648 \u0627\u0644\u062a\u0627\u0644\u064a:<\/p>\n<blockquote>\n<p>\u0627\u0644\u0635\u0645\u0627\u0645 \u0645\u0639\u062a\u0645\u062f \u0648\u0641\u0642 API 527.<\/p>\n<\/blockquote>\n<p>A test-standard reference, a completed seat-tightness test, a product capability statement, a code stamp and project approval are different forms of evidence.<\/p>\n<\/section>\n<section>\n<h2>\u0625\u0630\u0627 \u0638\u0647\u0631 \u062a\u0633\u0631\u0628 \u0642\u0631\u0628 \u0636\u063a\u0637 \u0627\u0644\u0636\u0628\u0637\u060c \u062d\u062f\u062f \u0645\u0633\u0627\u0631 \u0627\u0644\u062a\u0633\u0631\u0628 \u0642\u0628\u0644 \u062a\u0634\u062e\u064a\u0635 \u0627\u0644\u0635\u0645\u0627\u0645<\/h2>\n<p>\u0627\u0644\u062a\u0633\u0631\u0628 \u0642\u0631\u0628 \u0636\u063a\u0637 \u0627\u0644\u0636\u0628\u0637 \u0647\u0648 <strong>\u0639\u064e\u0631\u064e\u0636<\/strong>, \u060c \u0648\u0644\u064a\u0633 \u062a\u0634\u062e\u064a\u0635\u064b\u0627 \u0644\u0644\u0633\u0628\u0628 \u0627\u0644\u062c\u0630\u0631\u064a.<\/p>\n<p>\u0627\u0644\u0633\u0624\u0627\u0644 \u0627\u0644\u0645\u0641\u064a\u062f \u0627\u0644\u0623\u0648\u0644 \u0647\u0648:<\/p>\n<blockquote>\n<p>\u0623\u064a\u0646 \u064a\u064f\u0644\u0627\u062d\u0638 \u0627\u0644\u062a\u0633\u0631\u0628 \u0641\u0639\u0644\u064a\u064b\u0627\u060c \u0648\u0645\u0627 \u0643\u0627\u0646 \u0627\u0644\u0636\u063a\u0637 \u0648\u062d\u0627\u0644\u0629 \u0627\u0644\u062a\u0634\u063a\u064a\u0644 \u0639\u0646\u062f \u0638\u0647\u0648\u0631\u0647\u061f<\/p>\n<\/blockquote>\n<p>Only after that observation is clear should the engineer begin narrowing the possible cause. Manufacturer maintenance procedures reinforce this separation: for example, Emerson&#8217;s Anderson Greenwood Series 727 instructions check pilot vent leakage, manual blowdown leakage, field-test connection leakage and the main-valve outlet as distinct points during an internal leak test. <a href=\"https:\/\/www.emerson.com\/is\/content\/emerson\/en\/final-control\/pressure-management\/documents\/manuals-series-727-pilot-operated-safety-relief-valves-anderson-greenwood-en.pdf\" target=\"_blank\" rel=\"noopener noreferrer nofollow\">\u062a\u0639\u0644\u064a\u0645\u0627\u062a \u0635\u064a\u0627\u0646\u0629 Anderson Greenwood Series 727<\/a>.<\/p>\n<h3>\u0627\u0628\u062f\u0623 \u0628\u0627\u0644\u0645\u0644\u0627\u062d\u0638\u0629\u060c \u0644\u0627 \u0628\u0627\u0644\u0625\u0635\u0644\u0627\u062d<\/h3>\n<div class=\"zobai-table-wrap\" role=\"region\" aria-label=\"\u062c\u062f\u0648\u0644 \u0641\u0631\u0632 \u0627\u0633\u062a\u0643\u0634\u0627\u0641 \u0623\u062e\u0637\u0627\u0621 \u0627\u0644\u062a\u0633\u0631\u0628 \u0648\u0625\u0635\u0644\u0627\u062d\u0647\u0627\" tabindex=\"0\">\n<table>\n<thead>\n<tr>\n<th scope=\"col\">\u0645\u0627 \u0627\u0644\u0630\u064a \u062a\u0644\u0627\u062d\u0638\u0647<\/th>\n<th scope=\"col\">\u0645\u0627 \u064a\u062c\u0628 \u0627\u0644\u062a\u062d\u0642\u0642 \u0645\u0646\u0647 \u0628\u0639\u062f \u0630\u0644\u0643<\/th>\n<th scope=\"col\">\u0644\u0645\u0627\u0630\u0627<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>\u0627\u0644\u062a\u0633\u0631\u0628 \u0639\u0646\u062f \u0627\u0644\u0645\u062e\u0631\u062c \u0627\u0644\u0631\u0626\u064a\u0633\u064a<\/td>\n<td>\u0627\u0644\u0636\u063a\u0637 \u0627\u0644\u0641\u0639\u0644\u064a\u060c \u0648\u0636\u063a\u0637 \u0627\u0644\u0636\u0628\u0637\u060c \u0648\u0623\u0633\u0627\u0633 \u0627\u0644\u0625\u062d\u0643\u0627\u0645 \u0627\u0644\u0645\u0637\u0628\u0642\u060c \u0648\u062d\u0627\u0644\u0629 \u0627\u0644\u0635\u0645\u0627\u0645<\/td>\n<td>\u062a\u062f\u0641\u0642 \u0627\u0644\u0645\u062e\u0631\u062c \u0648\u062d\u062f\u0647 \u0644\u0627 \u064a\u062d\u062f\u062f \u0645\u0633\u0627\u0631 \u0627\u0644\u0625\u062d\u0643\u0627\u0645 \u0627\u0644\u062f\u0627\u062e\u0644\u064a \u0627\u0644\u062f\u0642\u064a\u0642<\/td>\n<\/tr>\n<tr>\n<td>\u0627\u0644\u062a\u062f\u0641\u0642 \u0639\u0646\u062f \u0645\u0633\u0627\u0631 \u062a\u0646\u0641\u064a\u0633\/\u062a\u062d\u0643\u0645 \u0627\u0644\u0628\u0627\u064a\u0644\u0648\u062a<\/td>\n<td>\u0646\u0648\u0639 \u0627\u0644\u0628\u0627\u064a\u0644\u0648\u062a\u060c \u0648\u062d\u0627\u0644\u0629 \u0627\u0644\u062a\u0634\u063a\u064a\u0644\u060c \u0648\u0633\u0644\u0648\u0643 \u0627\u0644\u0628\u0627\u064a\u0644\u0648\u062a \u0627\u0644\u0645\u0648\u062b\u0642<\/td>\n<td>\u0646\u0634\u0627\u0637 \u0627\u0644\u0628\u0627\u064a\u0644\u0648\u062a \u0644\u0627 \u064a\u062b\u0628\u062a \u062a\u0644\u0642\u0627\u0626\u064a\u064b\u0627 \u0648\u062c\u0648\u062f \u062a\u0633\u0631\u0628 \u0641\u064a \u0627\u0644\u0645\u0642\u0639\u062f \u0627\u0644\u0631\u0626\u064a\u0633\u064a<\/td>\n<\/tr>\n<tr>\n<td>\u062a\u0633\u0631\u0628 \u0639\u0646\u062f \u0648\u0635\u0644\u0629 \u062e\u0627\u0631\u062c\u064a\u0629 \u0623\u0648 \u0648\u0635\u0644\u0629 \u0623\u0646\u0627\u0628\u064a\u0628<\/td>\n<td>\u062d\u0627\u0644\u0629 \u0627\u0644\u062a\u0648\u0635\u064a\u0644 \u0648\u0627\u0644\u0625\u062d\u0643\u0627\u0645 \u0627\u0644\u062e\u0627\u0631\u062c\u064a<\/td>\n<td>\u0625\u0646\u0647 \u0645\u0633\u0627\u0631 \u0645\u062e\u062a\u0644\u0641 \u0639\u0646 \u0627\u0644\u062a\u0633\u0631\u0628 \u0645\u0646 \u0627\u0644\u0645\u0642\u0639\u062f \u0627\u0644\u0631\u0626\u064a\u0633\u064a<\/td>\n<\/tr>\n<tr>\n<td>\u064a\u0638\u0647\u0631 \u0627\u0644\u062a\u0633\u0631\u0628 \u0641\u0642\u0637 \u0642\u0631\u0628 \u0636\u063a\u0637 \u0627\u0644\u0636\u0628\u0637<\/td>\n<td>\u0639\u0644\u0627\u0642\u0629 \u0636\u063a\u0637 \u0627\u0644\u062a\u0634\u063a\u064a\u0644 \u0627\u0644\u0641\u0639\u0644\u064a \u0628\u0636\u063a\u0637 \u0627\u0644\u0636\u0628\u0637 \u0648\u0623\u0633\u0627\u0633 \u0627\u0644\u062a\u0634\u063a\u064a\u0644 \u0627\u0644\u062e\u0627\u0635 \u0628\u0627\u0644\u0645\u0646\u062a\u062c<\/td>\n<td>\u0642\u062f \u062a\u0643\u0648\u0646 \u0647\u0627\u0645\u0634 \u0627\u0644\u062a\u0634\u063a\u064a\u0644 \u0627\u0644\u0645\u0648\u062b\u0642 \u0644\u0644\u0635\u0645\u0627\u0645 \u0645\u0647\u0645\u064b\u0627<\/td>\n<\/tr>\n<tr>\n<td>\u064a\u0638\u0647\u0631 \u0627\u0644\u062a\u0633\u0631\u0628 \u0628\u0639\u062f \u062d\u062f\u062b \u0631\u0641\u0639 \u0623\u0648 \u0635\u064a\u0627\u0646\u0629<\/td>\n<td>Event history and applicable OEM inspection\/test basis<\/td>\n<td>\u0642\u062f \u062a\u062a\u063a\u064a\u0631 \u0627\u0644\u0641\u062d\u0648\u0635\u0627\u062a \u0630\u0627\u062a \u0627\u0644\u0635\u0644\u0629 \u0628\u0639\u062f \u062d\u062f\u062b \u062a\u0646\u0641\u064a\u0633 \u0623\u0648 \u062e\u062f\u0645\u0629<\/td>\n<\/tr>\n<tr>\n<td>\u0645\u0633\u0627\u0631 \u0627\u0644\u062a\u0633\u0631\u0628 \u0644\u0627 \u064a\u0632\u0627\u0644 \u063a\u064a\u0631 \u0645\u0639\u0631\u0648\u0641<\/td>\n<td>\u062a\u062d\u0633\u064a\u0646 \u0627\u0644\u0645\u0631\u0627\u0642\u0628\u0629 \u0623\u0648 \u062a\u0635\u0639\u064a\u062f \u0627\u0644\u0645\u0631\u0627\u062c\u0639\u0629<\/td>\n<td>\u0627\u0644\u062a\u0634\u062e\u064a\u0635 \u062f\u0648\u0646 \u0645\u0639\u0631\u0641\u0629 \u0627\u0644\u0645\u0633\u0627\u0631 \u062a\u062e\u0645\u064a\u0646<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<aside class=\"zobai-scenario\">\n<p><strong>\u0633\u064a\u0646\u0627\u0631\u064a\u0648 \u0647\u0646\u062f\u0633\u064a \u062a\u0648\u0636\u064a\u062d\u064a:<\/strong> leakage is reported after maintenance, but the only evidence is gas detected near the valve assembly. Before changing set pressure or pilot adjustment, separate the main outlet, pilot vent, tubing\/fittings and other external joints as observation points. If the leak cannot be localized safely, the correct next step is controlled testing or OEM-qualified inspection\u2014not adjustment by inference.<\/p>\n<\/aside>\n<h3>\u062b\u0645 \u0627\u0641\u0635\u0644 \u0628\u064a\u0646 \u0638\u0631\u0648\u0641 \u0627\u0644\u0646\u0638\u0627\u0645 \u0648\u0638\u0631\u0648\u0641 \u0627\u0644\u0635\u0645\u0627\u0645<\/h3>\n<p>\u0645\u0645\u0643\u0646 <strong>\u0645\u062a\u063a\u064a\u0631\u0627\u062a \u0627\u0644\u0646\u0638\u0627\u0645 \u0623\u0648 \u0627\u0644\u062a\u0634\u063a\u064a\u0644<\/strong> \u064a\u062a\u0636\u0645\u0646:<\/p>\n<ul>\n<li>\u0627\u0644\u0636\u063a\u0637 \u0627\u0644\u0641\u0639\u0644\u064a \u0628\u0627\u0644\u0646\u0633\u0628\u0629 \u0625\u0644\u0649 \u0636\u063a\u0637 \u0627\u0644\u0636\u0628\u0637\u061b;<\/li>\n<li>steady versus transient or cycling pressure;<\/li>\n<li>\u0627\u0644\u0636\u063a\u0637 \u0627\u0644\u062e\u0644\u0641\u064a \u0623\u0648 \u0636\u063a\u0637 \u0627\u0644\u062c\u0627\u0646\u0628 \u0627\u0644\u0633\u0641\u0644\u064a \u0639\u0646\u062f \u0627\u0644\u0627\u0642\u062a\u0636\u0627\u0621\u061b;<\/li>\n<li>internal versus remote sensing arrangement;<\/li>\n<li>temperature and medium state where they affect the selected valve;<\/li>\n<li>dirty, wet, contaminated, polymerizing or particulate-laden service where the pilot\/control path may be sensitive.<\/li>\n<\/ul>\n<p>\u0645\u0645\u0643\u0646 <strong>\u0645\u062a\u063a\u064a\u0631\u0627\u062a \u0627\u0644\u0635\u0645\u0627\u0645\/\u0627\u0644\u062a\u0643\u0648\u064a\u0646<\/strong> \u064a\u062a\u0636\u0645\u0646:<\/p>\n<ul>\n<li>pilot type and action;<\/li>\n<li>\u062d\u0627\u0644\u0629 \u0627\u0644\u0645\u0642\u0639\u062f \u0627\u0644\u0631\u0626\u064a\u0633\u064a \u0623\u0648 \u0627\u0644\u0633\u062f\u0627\u062f\u061b;<\/li>\n<li>\u062d\u0627\u0644\u0629 \u0645\u0633\u0627\u0631 \u0627\u0644\u0628\u0627\u064a\u0644\u0648\u062a\/\u0627\u0644\u062a\u062d\u0643\u0645\u061b;<\/li>\n<li>filter, sensing line or small control passage condition where fitted;<\/li>\n<li>relevant internal seals and soft goods;<\/li>\n<li>the documented main-valve and pilot leakage test points.<\/li>\n<\/ul>\n<p>\u0647\u0630\u0647 \u0641\u0626\u0627\u062a \u062a\u062d\u0642\u064a\u0642 \u0648\u0644\u064a\u0633\u062a \u0623\u0633\u0628\u0627\u0628\u064b\u0627 \u062c\u0630\u0631\u064a\u0629 \u062a\u0644\u0642\u0627\u0626\u064a\u0629.<\/p>\n<p>A high operating pressure does not prove the valve is defective. Contaminated service does not prove contamination caused the leakage. A pilot vent does not prove the main seat is leaking. Conversely, a previous API 527 pass does not prove that every later in-service leak observation is acceptable.<\/p>\n<h3>\u062a\u0648\u0642\u0641 \u0642\u0628\u0644 \u0623\u0646 \u064a\u062a\u062d\u0648\u0644 \u0627\u0644\u062a\u0634\u062e\u064a\u0635 \u0627\u0644\u0639\u0627\u0645 \u0625\u0644\u0649 \u0646\u0635\u064a\u062d\u0629 \u0636\u0628\u0637 \u063a\u064a\u0631 \u0622\u0645\u0646\u0629<\/h3>\n<p>\u0644\u0627 \u064a\u0646\u0628\u063a\u064a \u0644\u0645\u0642\u0627\u0644 \u0639\u0627\u0645 \u0623\u0646 \u064a\u0648\u062c\u0651\u0647 \u0627\u0644\u0642\u0627\u0631\u0626 \u0625\u0644\u0649 \u062a\u063a\u064a\u064a\u0631:<\/p>\n<ul>\n<li>\u0636\u0628\u0637 \u0627\u0644\u0636\u063a\u0637\u061b;<\/li>\n<li>\u0636\u0628\u0637 \u0627\u0644\u0628\u0627\u064a\u0644\u0648\u062a\u061b;<\/li>\n<li>\u0627\u0644\u0628\u0644\u0648\u062f\u0627\u0648\u0646\u061b;<\/li>\n<li>\u0625\u0639\u062f\u0627\u062f\u0627\u062a \u0627\u0644\u0646\u0627\u0628\u0636 \u0623\u0648 \u0627\u0644\u0633\u064a\u0644 \u0627\u0644\u062f\u0627\u062e\u0644\u064a\u0629\u061b;<\/li>\n<li>\u062a\u0643\u0648\u064a\u0646 \u0627\u0644\u0627\u0633\u062a\u0634\u0639\u0627\u0631.<\/li>\n<\/ul>\n<p>Those actions require the correct valve procedure and qualified review because they can affect the protection function and can invalidate the comparison between observed field behavior and the original test basis.<\/p>\n<p>\u0625\u0630\u0627 \u062a\u0639\u0627\u0631\u0636 \u0627\u0644\u0633\u0644\u0648\u0643 \u0627\u0644\u0645\u0644\u0627\u062d\u0638 \u0645\u0639 \u0623\u0633\u0627\u0633 OEM \u0623\u0648 \u0623\u0633\u0627\u0633 \u0627\u0644\u0627\u062e\u062a\u0628\u0627\u0631 \u0627\u0644\u0645\u0639\u0645\u0648\u0644 \u0628\u0647\u060c \u0623\u0648 \u062a\u0639\u0630\u0651\u0631 \u062a\u062d\u062f\u064a\u062f \u0645\u0633\u0627\u0631 \u0627\u0644\u062a\u0633\u0631\u0628 \u0628\u0623\u0645\u0627\u0646\u060c \u0641\u0627\u0646\u062a\u0642\u0644 \u0625\u0644\u0649 \u0645\u0631\u0627\u062c\u0639\u0629 \u0647\u0646\u062f\u0633\u064a\u0629 \u0623\u0648 \u062e\u062f\u0645\u064a\u0629 \u062e\u0627\u0635\u0629 \u0628\u0627\u0644\u0645\u0646\u062a\u062c \u0628\u062f\u0644\u064b\u0627 \u0645\u0646 \u0627\u0644\u0627\u0633\u062a\u0645\u0631\u0627\u0631 \u0628\u0646\u0627\u0621\u064b \u0639\u0644\u0649 \u0627\u0644\u0627\u0641\u062a\u0631\u0627\u0636.<\/p>\n<\/section>\n<section>\n<h2>\u0645\u0627 \u0627\u0644\u0630\u064a \u064a\u062c\u0628 \u0627\u0644\u062a\u062d\u0642\u0642 \u0645\u0646\u0647 \u0642\u0628\u0644 \u0642\u0628\u0648\u0644 \u0627\u0644\u0635\u0645\u0627\u0645 \u0623\u0648 \u0631\u0641\u0636\u0647 \u0623\u0648 \u062a\u0635\u0639\u064a\u062f\u0647\u061f<\/h2>\n<p>A technically useful supplier inquiry should allow the engineer to reconstruct the condition in which the leakage was observed and compare it with the correct test or operating basis.<\/p>\n<p>\u0625\u0631\u0633\u0627\u0644 \u0641\u0642\u0637:<\/p>\n<blockquote>\n<p>\u0635\u0645\u0627\u0645 \u0623\u0645\u0627\u0646 \u064a\u0639\u0645\u0644 \u0628\u0627\u0644\u0628\u0627\u064a\u0644\u0648\u062a \u064a\u062a\u0633\u0631\u0628 \u0642\u0631\u0628 \u0636\u063a\u0637 \u0627\u0644\u0636\u0628\u0637 \u2014 \u064a\u0631\u062c\u0649 \u0627\u0644\u0625\u0641\u0627\u062f\u0629.<\/p>\n<\/blockquote>\n<p>\u064a\u062a\u0631\u0643 \u0645\u062a\u063a\u064a\u0631\u0627\u062a \u0643\u062b\u064a\u0631\u0629 \u062f\u0648\u0646 \u062d\u0644.<\/p>\n<h3>1. \u062d\u0627\u0644\u0629 \u0627\u0644\u0636\u063a\u0637<\/h3>\n<p>\u064a\u0631\u062c\u0649 \u062a\u0642\u062f\u064a\u0645:<\/p>\n<ul>\n<li>\u0636\u063a\u0637 \u0627\u0644\u0636\u0628\u0637 \u0627\u0644\u0645\u062d\u062f\u062f\u061b;<\/li>\n<li>\u0636\u063a\u0637 \u0627\u0644\u062a\u0634\u063a\u064a\u0644 \u0627\u0644\u0637\u0628\u064a\u0639\u064a \u0627\u0644\u0641\u0639\u0644\u064a\u061b;<\/li>\n<li>\u0627\u0644\u0636\u063a\u0637 \u0627\u0644\u0630\u064a \u064a\u0638\u0647\u0631 \u0639\u0646\u062f\u0647 \u0627\u0644\u062a\u0633\u0631\u0628\u061b;<\/li>\n<li>\u0645\u0627 \u0625\u0630\u0627 \u0643\u0627\u0646 \u0627\u0644\u0636\u063a\u0637 \u062b\u0627\u0628\u062a\u064b\u0627 \u0623\u0645 \u0645\u062a\u0632\u0627\u064a\u062f\u064b\u0627 \u0623\u0645 \u0645\u062a\u0646\u0627\u0642\u0635\u064b\u0627 \u0623\u0645 \u0645\u062a\u0630\u0628\u0630\u0628\u064b\u0627\u061b;<\/li>\n<li>\u0636\u063a\u0637 \u0627\u0644\u0645\u062e\u0631\u062c\/\u0627\u0644\u0636\u063a\u0637 \u0627\u0644\u062e\u0644\u0641\u064a \u062d\u064a\u062b \u064a\u0646\u0637\u0628\u0642 \u0630\u0644\u0643.<\/li>\n<\/ul>\n<p>The pressure ratio only becomes useful when compared against documentation for the actual valve. Do not compare a field operating ratio directly with an API 527 test-pressure ratio unless the governing procedure explicitly makes that comparison.<\/p>\n<h3>2. \u062a\u0643\u0648\u064a\u0646 \u0627\u0644\u0635\u0645\u0627\u0645 \u0648\u0627\u0644\u0628\u0627\u064a\u0644\u0648\u062a \u0627\u0644\u062f\u0642\u064a\u0642<\/h3>\n<p>\u062d\u062f\u062f:<\/p>\n<ul>\n<li>\u0627\u0644\u062c\u0647\u0629 \u0627\u0644\u0645\u0635\u0646\u0639\u0629\u061b;<\/li>\n<li>\u0633\u0644\u0633\u0644\u0629\/\u0637\u0631\u0627\u0632 \u0627\u0644\u0635\u0645\u0627\u0645\u061b;<\/li>\n<li>\u0646\u0648\u0639 \u0627\u0644\u0628\u0627\u064a\u0644\u0648\u062a\u061b;<\/li>\n<li>\u062a\u0631\u062a\u064a\u0628 \u0627\u0644\u0641\u062a\u062d \u0627\u0644\u0633\u0631\u064a\u0639 \u0623\u0648 \u0627\u0644\u062a\u0639\u062f\u064a\u0644\u064a \u062d\u064a\u062b \u064a\u0646\u0637\u0628\u0642\u061b;<\/li>\n<li>\u062a\u0631\u0643\u064a\u0628 \u0627\u0644\u0645\u0642\u0639\u062f\/\u0627\u0644\u0639\u0646\u0635\u0631 \u0627\u0644\u0645\u062d\u0643\u0645 \u0625\u0630\u0627 \u0643\u0627\u0646 \u0630\u0627 \u0635\u0644\u0629\u061b;<\/li>\n<li>\u062a\u0631\u062a\u064a\u0628 \u0627\u0633\u062a\u0634\u0639\u0627\u0631 \u0627\u0644\u0636\u063a\u0637\u061b;<\/li>\n<li>\u0627\u0644\u062e\u064a\u0627\u0631\u0627\u062a \u0623\u0648 \u0627\u0644\u0645\u0644\u062d\u0642\u0627\u062a \u0630\u0627\u062a \u0627\u0644\u0635\u0644\u0629.<\/li>\n<\/ul>\n<p>Configuration matters because near-set behavior is not a category-wide property. ZOBAI&#8217;s current pilot-operated safety-valve page, for example, distinguishes multiple pilot actions, sensing methods and seat\/seal options rather than one universal arrangement. That product-page taxonomy is useful for defining an RFQ, but it is not evidence for an unlisted near-set tightness percentage.<\/p>\n<p>\u0625\u0630\u0627 \u0627\u0646\u062a\u0642\u0644\u062a \u0627\u0644\u0645\u0647\u0645\u0629 \u0645\u0646 \u0627\u0644\u062a\u0634\u062e\u064a\u0635 \u0625\u0644\u0649 \u0627\u062e\u062a\u064a\u0627\u0631 \u0627\u0644\u0645\u0646\u062a\u062c\u060c \u0631\u0627\u062c\u0639 <a href=\"https:\/\/zobai.com\/ar\/safety-valves\/pilot-operated-safety-valves\/\">\u0635\u0645\u0627\u0645\u0627\u062a \u0627\u0644\u0623\u0645\u0627\u0646 \u0627\u0644\u062a\u064a \u062a\u0639\u0645\u0644 \u0628\u0627\u0644\u0628\u0627\u064a\u0644\u0648\u062a \u0645\u0646 ZOBAI<\/a>.<\/p>\n<h3>3. \u0633\u064a\u0627\u0642 \u0627\u0644\u062e\u062f\u0645\u0629 \u0648\u0627\u0644\u0627\u062e\u062a\u0628\u0627\u0631<\/h3>\n<p>\u0648\u0636\u0651\u062d \u0645\u0627 \u0625\u0630\u0627 \u0644\u0648\u062d\u0638 \u0627\u0644\u062a\u0633\u0631\u064a\u0628 \u0623\u062b\u0646\u0627\u0621:<\/p>\n<ul>\n<li>\u0627\u062e\u062a\u0628\u0627\u0631 \u0625\u062d\u0643\u0627\u0645 \u0627\u0644\u0645\u0642\u0639\u062f \u0639\u0644\u0649 \u0645\u0646\u0635\u0629 \u0627\u0644\u0627\u062e\u062a\u0628\u0627\u0631\u061b;<\/li>\n<li>\u0627\u0644\u062a\u062d\u0642\u0642 \u0627\u0644\u0645\u064a\u062f\u0627\u0646\u064a\u061b;<\/li>\n<li>\u0627\u0644\u062a\u0634\u063a\u064a\u0644 \u0627\u0644\u0639\u0627\u062f\u064a \u0644\u0644\u0645\u0635\u0646\u0639\u061b;<\/li>\n<li>\u0628\u062f\u0621 \u0627\u0644\u062a\u0634\u063a\u064a\u0644 \u0623\u0648 \u0623\u064a \u062d\u0627\u0644\u0629 \u0639\u0627\u0628\u0631\u0629 \u0623\u062e\u0631\u0649\u061b;<\/li>\n<li>\u062d\u0627\u0644\u0629 \u0628\u0639\u062f \u0631\u0641\u0639 \u0627\u0644\u0635\u0645\u0627\u0645.<\/li>\n<\/ul>\n<p>Include the medium, relevant phase\/state, temperature, contamination condition, and whether the test medium and procedure match the required acceptance basis.<\/p>\n<h3>4. \u0648\u0635\u0641 \u0627\u0644\u062a\u0633\u0631\u064a\u0628 \u0646\u0641\u0633\u0647<\/h3>\n<p>\u0633\u062c\u0651\u0644:<\/p>\n<ul>\n<li>\u0645\u0643\u0627\u0646 \u0645\u0644\u0627\u062d\u0638\u062a\u0647\u061b;<\/li>\n<li>how it was observed or measured;<\/li>\n<li>whether it is continuous, intermittent or associated with pilot action;<\/li>\n<li>the pressure at which it begins or stops, if known;<\/li>\n<li>whether the main outlet, pilot vent and external joints were distinguished.<\/li>\n<\/ul>\n<p>\u201c\u062a\u0633\u0631\u0628 \u0639\u0646\u062f \u0627\u0644\u0645\u062e\u0631\u062c \u0627\u0644\u0631\u0626\u064a\u0633\u064a \u0639\u0646\u062f \u0636\u063a\u0637 \u062a\u0634\u063a\u064a\u0644 \u0645\u0639\u0631\u0648\u0641\u201d \u0623\u0643\u062b\u0631 \u0642\u0627\u0628\u0644\u064a\u0629 \u0644\u0644\u062a\u0646\u0641\u064a\u0630 \u0645\u0646 \u201c\u0627\u0644\u0635\u0645\u0627\u0645 \u064a\u062a\u0633\u0631\u0628\u201d.\u201d<\/p>\n<h3>5. \u062a\u062d\u062f\u064a\u062f \u0623\u0633\u0627\u0633 \u0627\u0644\u0642\u0628\u0648\u0644<\/h3>\n<p>\u0642\u062f\u0651\u0645 \u0645\u0627 \u064a\u0646\u0637\u0628\u0642:<\/p>\n<ul>\n<li>\u0645\u062a\u0637\u0644\u0628 \u0627\u0644\u0625\u062d\u0643\u0627\u0645 \u0627\u0644\u062e\u0627\u0635 \u0628\u0627\u0644\u0645\u0634\u0631\u0648\u0639\u061b;<\/li>\n<li>controlled API 527 edition and test basis where used;<\/li>\n<li>\u0625\u062c\u0631\u0627\u0621 \u0627\u062e\u062a\u0628\u0627\u0631 \u0627\u0644\u062c\u0647\u0629 \u0627\u0644\u0645\u0635\u0646\u0639\u0629 \u0627\u0644\u0623\u0635\u0644\u064a\u0629 (OEM)\u061b;<\/li>\n<li>\u0645\u0648\u0627\u0635\u0641\u0627\u062a \u0627\u0644\u0645\u0634\u062a\u0631\u064a\u061b;<\/li>\n<li>available supplier test report, including test medium, test pressure and acceptance result;<\/li>\n<li>manufacturer operating-pressure claim for the exact valve, if one is being relied upon.<\/li>\n<\/ul>\n<p>\u0628\u062f\u0648\u0646 \u0623\u0633\u0627\u0633 \u0642\u0628\u0648\u0644\u060c \u0644\u0627 \u064a\u0645\u0643\u0646 \u062a\u062d\u0648\u064a\u0644 \u0627\u0644\u0645\u0644\u0627\u062d\u0638\u0629 \u0628\u0634\u0643\u0644 \u0645\u0648\u062b\u0648\u0642 \u0625\u0644\u0649 \u201c\u0646\u0627\u062c\u062d\u201d \u0623\u0648 \u201c\u0641\u0627\u0634\u0644\u201d \u0627\u0633\u062a\u0646\u0627\u062f\u064b\u0627 \u0641\u0642\u0637 \u0625\u0644\u0649 \u0646\u0633\u0628\u0629 \u0645\u0626\u0648\u064a\u0629 \u0639\u0627\u0645\u0629 \u0639\u0644\u0649 \u0627\u0644\u0625\u0646\u062a\u0631\u0646\u062a.<\/p>\n<h3>\u0642\u0631\u0627\u0631 \u0641\u0631\u0632 \u0647\u0646\u062f\u0633\u064a \u0639\u0645\u0644\u064a<\/h3>\n<p><strong>\u0648\u0627\u0635\u0644 \u0627\u0644\u062a\u0642\u064a\u064a\u0645<\/strong> \u0639\u0646\u062f\u0645\u0627 \u062a\u0643\u0648\u0646 \u0647\u0648\u064a\u0629 \u0627\u0644\u0635\u0645\u0627\u0645 \u0648\u062d\u0627\u0644\u0629 \u0627\u0644\u0636\u063a\u0637 \u0648\u0645\u0633\u0627\u0631 \u0627\u0644\u062a\u0633\u0631\u0628 \u0648\u0623\u0633\u0627\u0633 \u0627\u0644\u0642\u0628\u0648\u0644 \u0627\u0644\u0645\u0639\u0645\u0648\u0644 \u0628\u0647 \u0645\u0639\u0631\u0648\u0641\u0629.<\/p>\n<p><strong>\u0623\u0648\u0642\u0641 \u0627\u0644\u062d\u0643\u0645<\/strong> when a critical input is still unknown\u2014for example, if \u201cleakage\u201d has not been localized or if the only available percentage belongs to another valve family.<\/p>\n<p><strong>\u0635\u0639\u0651\u062f \u0644\u0644\u0645\u0631\u0627\u062c\u0639\u0629 \u0627\u0644\u062e\u0627\u0635\u0629 \u0628\u0627\u0644\u0645\u0646\u062a\u062c<\/strong> when the observed behavior conflicts with documented valve or test requirements, when the exact API 527\/OEM acceptance basis cannot be reconstructed, or when diagnosis would require OEM-specific inspection or adjustment.<\/p>\n<p>These are article-level engineering screening labels, not API, ASME, ISO or regulatory classifications.<\/p>\n<aside class=\"zobai-cta\">\n<p><strong>\u0647\u0644 \u062a\u062d\u062a\u0627\u062c \u0625\u0644\u0649 \u0645\u0631\u0627\u062c\u0639\u0629 \u0635\u0645\u0627\u0645 \u064a\u0639\u0645\u0644 \u0628\u0627\u0644\u0628\u0627\u064a\u0644\u0648\u062a \u064a\u0633\u0631\u0651\u0628 \u0642\u0631\u0628 \u0636\u063a\u0637 \u0627\u0644\u0636\u0628\u0637\u061f<\/strong><\/p>\n<p>\u0642\u062f\u0651\u0645 \u0628\u064a\u0627\u0646\u0627\u062a \u0627\u0644\u0634\u0631\u0643\u0629 \u0627\u0644\u0645\u0635\u0646\u0639\u0629 \u0644\u0644\u0635\u0645\u0627\u0645 \u0648\u0627\u0644\u0637\u0631\u0627\u0632\u060c \u0648\u062a\u0643\u0648\u064a\u0646 \u0627\u0644\u0628\u0627\u064a\u0644\u0648\u062a\u060c \u0648\u0636\u063a\u0637 \u0627\u0644\u0636\u0628\u0637\u060c \u0648\u0636\u063a\u0637 \u0627\u0644\u062a\u0634\u063a\u064a\u0644 \u0627\u0644\u0641\u0639\u0644\u064a\u060c \u0648\u0627\u0644\u0648\u0633\u0637 \u0627\u0644\u062e\u062f\u0645\u064a\u060c \u0648\u0645\u0648\u0636\u0639 \u0627\u0644\u062a\u0633\u0631\u0628 \u0627\u0644\u0645\u0644\u0627\u062d\u0638\u060c \u0648\u0623\u0633\u0627\u0633 \u0625\u062d\u0643\u0627\u0645 \u0627\u0644\u0645\u0642\u0639\u062f \u0623\u0648 \u0627\u0644\u0627\u062e\u062a\u0628\u0627\u0631 \u0627\u0644\u0645\u0639\u0645\u0648\u0644 \u0628\u0647. \u064a\u0645\u0643\u0646 \u0644\u0640 ZOBAI \u0627\u0633\u062a\u062e\u062f\u0627\u0645 \u0647\u0630\u0647 \u0627\u0644\u0645\u062f\u062e\u0644\u0627\u062a \u0644\u0645\u0646\u0627\u0642\u0634\u0629 \u0647\u0646\u062f\u0633\u064a\u0629 \u0623\u0648\u0644\u064a\u0629 \u0648\u0637\u0644\u0628 \u0639\u0631\u0636 \u0633\u0639\u0631. \u064a\u062c\u0628 \u0623\u0646 \u062a\u062a\u0628\u0639 \u0642\u0631\u0627\u0631\u0627\u062a \u0627\u0644\u0642\u0628\u0648\u0644 \u0623\u0648 \u0627\u0644\u0636\u0628\u0637 \u0623\u0648 \u0627\u0644\u0635\u064a\u0627\u0646\u0629 \u0627\u0644\u0646\u0647\u0627\u0626\u064a\u0629 \u0648\u062b\u0627\u0626\u0642 \u0627\u0644\u0635\u0645\u0627\u0645 \u0627\u0644\u0645\u0639\u0645\u0648\u0644 \u0628\u0647\u0627 \u0648\u0645\u062a\u0637\u0644\u0628\u0627\u062a \u0627\u0644\u0645\u0634\u0631\u0648\u0639 \u0648\u0627\u0644\u0645\u0631\u0627\u062c\u0639\u0629 \u0627\u0644\u0647\u0646\u062f\u0633\u064a\u0629 \u0627\u0644\u0645\u0624\u0647\u0644\u0629.<\/p>\n<p><a href=\"https:\/\/zobai.com\/ar\/ask-an-engineer\/\">\u0627\u0633\u0623\u0644 \u0645\u0647\u0646\u062f\u0633 \u0635\u0645\u0627\u0645\u0627\u062a \u0627\u0644\u0623\u0645\u0627\u0646<\/a><\/p>\n<\/aside>\n<\/section>\n<p><!-- ZOBAI_CONTENT_ENHANCEMENT_20260924 --><\/p>\n<section class=\"zobai-architecture-example\" aria-labelledby=\"balanced-architecture-example\">\n<h2 id=\"balanced-architecture-example\">\u0645\u062b\u0627\u0644 \u0639\u0644\u0649 \u0627\u0644\u0642\u0631\u0627\u0631: \u0645\u0642\u0627\u0631\u0646\u0629 \u0628\u064a\u0646 \u062a\u0635\u0645\u064a\u0645\u064a\u0646 \u0645\u062a\u0648\u0627\u0632\u0646\u064a\u0646<\/h2>\n<p>If near-set leakage leads a project to compare a pilot-operated valve with a balanced spring-loaded alternative, keep the comparison tied to the actual leakage problem. The question is not which architecture is \u201cbetter\u201d; it is which design can document the required operating margin, seat-tightness basis and leak-path behavior for the service.<\/p>\n<div class=\"zobai-table-wrap\" role=\"region\" aria-label=\"Seat tightness comparison questions for pilot operated and balanced bellows alternatives\" tabindex=\"0\">\n<table>\n<thead>\n<tr>\n<th scope=\"col\">\u0639\u0627\u0645\u0644 \u0627\u0644\u0642\u0631\u0627\u0631<\/th>\n<th scope=\"col\">Pilot-operated question<\/th>\n<th scope=\"col\">Balanced-bellows alternative question<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Near-set operating claim<\/td>\n<td>What operating-pressure-to-set-pressure relationship is documented for the exact pilot and main-valve configuration?<\/td>\n<td>What normal operating margin and seat-tightness behavior are documented for the exact spring-loaded design?<\/td>\n<\/tr>\n<tr>\n<td>Leak-path diagnosis<\/td>\n<td>Can the main outlet, pilot vent, sensing path and external joints be distinguished during the review?<\/td>\n<td>Can main-seat leakage be separated from bonnet\/bellows vent or external leakage paths?<\/td>\n<\/tr>\n<tr>\n<td>Contamination sensitivity<\/td>\n<td>Can the service foul the pilot, filter, sensing line or control passages and thereby affect closing pressure or pilot behavior?<\/td>\n<td>Can deposits or corrosion affect the seat, guide, bellows movement or vent condition?<\/td>\n<\/tr>\n<tr>\n<td>\u062f\u0644\u064a\u0644 \u0625\u062d\u0643\u0627\u0645 \u0627\u0644\u0645\u0642\u0639\u062f<\/td>\n<td>What API 527 or OEM procedure applies to the assembled pilot\/main-valve configuration?<\/td>\n<td>What API 527 or OEM procedure applies to the spring-loaded valve and its seat type?<\/td>\n<\/tr>\n<tr>\n<td>Maintenance after leakage<\/td>\n<td>What OEM procedure governs inspection of the main seat, pilot seats, seals and sensing components?<\/td>\n<td>What OEM procedure governs seat condition, bellows integrity, guide condition and recalibration?<\/td>\n<\/tr>\n<tr>\n<td>Acceptance decision<\/td>\n<td>Can the supplier demonstrate both the required operating envelope and the applicable leakage-test result?<\/td>\n<td>Can the supplier demonstrate the required operating margin and applicable seat-tightness result without relying on a generic architecture claim?<\/td>\n<\/tr>\n<\/tbody>\n<\/table><\/div>\n<p>If a bellows design is being considered because a pilot-operated valve cannot document the required near-set operating behavior or service suitability, also review <a href=\"https:\/\/zobai.com\/ar\/blog\/when-a-bellows-balanced-valve-is-not-the-right-solution\/\">\u0645\u062a\u0649 \u0644\u0627 \u064a\u0643\u0648\u0646 \u0627\u0644\u0635\u0645\u0627\u0645 \u0627\u0644\u0645\u062a\u0648\u0627\u0632\u0646 \u0628\u0645\u0646\u0641\u0627\u062e \u0647\u0648 \u0627\u0644\u062d\u0644 \u0627\u0644\u0645\u0646\u0627\u0633\u0628<\/a>. That comparison should be treated as a separate architecture decision, not as a workaround for an unresolved API 527 or leak-path question.<\/p>\n<\/section>\n<section class=\"zobai-faq-section\" aria-labelledby=\"pilot-seat-tightness-faq\">\n<h2 id=\"pilot-seat-tightness-faq\">Frequently Asked Questions About Pilot-Operated Safety Valve Seat Tightness Near Set Pressure<\/h2>\n<div class=\"zobai-faq-item\">\n<h3>Is API 527 test pressure the same as normal operating pressure?<\/h3>\n<p>No. API 527 defines controlled seat-tightness testing, while normal operating pressure is the real process pressure during service. A test pressure used for API 527 acceptance should not be reused as a plant operating recommendation unless the applicable valve documentation explicitly supports that operating condition.<\/p>\n<\/p><\/div>\n<div class=\"zobai-faq-item\">\n<h3>Does \u201ctight to 98% of set pressure\u201d mean every pilot-operated safety valve can operate there?<\/h3>\n<p>No. Near-set percentages published by manufacturers belong to identified product families and conditions. They do not create a universal POSV operating rule and they are not automatically the API 527 test-pressure criterion.<\/p>\n<\/p><\/div>\n<div class=\"zobai-faq-item\">\n<h3>Can a pilot-operated safety valve pass API 527 and still leak in service?<\/h3>\n<p>Yes, because a controlled bench test and installed operation are different conditions. A field leak still has to be localized and reviewed against the actual pressure history, service medium, pilot state, downstream condition, valve condition and OEM operating envelope.<\/p>\n<\/p><\/div>\n<div class=\"zobai-faq-item\">\n<h3>Does flow from the pilot vent prove the main valve seat is leaking?<\/h3>\n<p>No. Pilot vent flow can be associated with pilot operation or a pilot\/control-path leak depending on the design and operating state. Main-seat leakage should be confirmed at the main outlet or by the applicable controlled test procedure.<\/p>\n<\/p><\/div>\n<div class=\"zobai-faq-item\">\n<h3>What information should be recorded before judging near-set leakage?<\/h3>\n<p>Record the valve manufacturer and model, pilot type, set pressure, actual operating pressure, pressure trend, service medium and temperature, back pressure where relevant, leak location, operating state, seat\/seal configuration, and the exact API 527, OEM or project acceptance basis being used.<\/p>\n<\/p><\/div>\n<div class=\"zobai-faq-item\">\n<h3>Should set pressure or pilot adjustment be changed to stop leakage?<\/h3>\n<p>Not from a general article or a percentage comparison. Adjustment can change the protection function and must follow the correct OEM procedure, applicable project requirements and qualified engineering or service review.<\/p>\n<\/p><\/div>\n<\/section>\n<\/article>","protected":false},"excerpt":{"rendered":"<p>\u062a\u0639\u0631\u0651\u0641 \u0639\u0644\u0649 \u0643\u064a\u0641\u064a\u0629 \u062a\u0642\u064a\u064a\u0645 \u0625\u062d\u0643\u0627\u0645 \u0645\u0642\u0639\u062f \u0635\u0645\u0627\u0645 \u0627\u0644\u0623\u0645\u0627\u0646 \u0627\u0644\u0630\u064a \u064a\u0639\u0645\u0644 \u0628\u0627\u0644\u0628\u0627\u064a\u0644\u0648\u062a \u0642\u0631\u0628 \u0636\u063a\u0637 \u0627\u0644\u0636\u0628\u0637\u060c \u0648\u062a\u0641\u0633\u064a\u0631 API 527\u060c \u0648\u0627\u0644\u062a\u062d\u0642\u0642 \u0645\u0646 \u062d\u062f\u0648\u062f \u0627\u0644\u062a\u0633\u0631\u064a\u0628 \u0627\u0644\u062e\u0627\u0635\u0629 \u0628\u0627\u0644\u0645\u0646\u062a\u062c.<\/p>","protected":false},"author":2,"featured_media":56879,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[75],"tags":[],"class_list":["post-56813","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-installation-maintenance-troubleshooting"],"_links":{"self":[{"href":"https:\/\/zobai.com\/ar\/wp-json\/wp\/v2\/posts\/56813","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/zobai.com\/ar\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/zobai.com\/ar\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/zobai.com\/ar\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/zobai.com\/ar\/wp-json\/wp\/v2\/comments?post=56813"}],"version-history":[{"count":0,"href":"https:\/\/zobai.com\/ar\/wp-json\/wp\/v2\/posts\/56813\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/zobai.com\/ar\/wp-json\/wp\/v2\/media\/56879"}],"wp:attachment":[{"href":"https:\/\/zobai.com\/ar\/wp-json\/wp\/v2\/media?parent=56813"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/zobai.com\/ar\/wp-json\/wp\/v2\/categories?post=56813"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/zobai.com\/ar\/wp-json\/wp\/v2\/tags?post=56813"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}