{"id":56806,"date":"2026-09-11T08:27:30","date_gmt":"2026-09-11T08:27:30","guid":{"rendered":"https:\/\/zobai.com\/?p=56806"},"modified":"2026-09-11T10:14:06","modified_gmt":"2026-09-11T10:14:06","slug":"thermal-expansion-relief-valve-for-blocked-in-liquid-lines","status":"publish","type":"post","link":"https:\/\/zobai.com\/zh\/blog\/thermal-expansion-relief-valve-for-blocked-in-liquid-lines\/","title":{"rendered":"\u7528\u4e8e\u5c01\u95ed\u6db2\u4f53\u7ba1\u9053\u7684\u70ed\u81a8\u80c0\u6cc4\u538b\u9600"},"content":{"rendered":"<style> .zobai-trv-guide { max-width: 100%; overflow-wrap: anywhere; } .zobai-trv-guide .z-table-wrap { width: 100%; overflow-x: auto; -webkit-overflow-scrolling: touch; margin: 1.25rem 0; } .zobai-trv-guide .z-table-wrap table { width: 100%; min-width: 680px; border-collapse: collapse; } .zobai-trv-guide .z-table-wrap th, .zobai-trv-guide .z-table-wrap td { vertical-align: top; padding: 0.75rem; } .zobai-trv-guide blockquote { margin: 1.25rem 0; padding-left: 1rem; } .zobai-trv-guide .z-decision-chain { margin: 1.25rem 0; font-weight: 600; } .zobai-trv-guide .z-cta { margin-top: 2rem; padding: 1.25rem; } @media (max-width: 767px) { .zobai-trv-guide .z-table-wrap table { min-width: 620px; } .zobai-trv-guide .z-table-wrap th, .zobai-trv-guide .z-table-wrap td { padding: 0.625rem; } } <\/style>\n<article class=\"zobai-trv-guide\">\n<p> \u5c01\u95ed\u6db2\u4f53\u7ba1\u7ebf\u4e2d\uff0c\u5f53\u6db2\u4f53\u88ab\u56f0\u5728\u786e\u5b9a\u7684\u538b\u529b\u8fb9\u754c\u5185\uff0c\u4e14\u6e29\u5ea6\u5347\u9ad8\u65f6\u6ca1\u6709\u8db3\u591f\u7a7a\u95f4\u6216\u5176\u4ed6\u9002\u5f53\u9014\u5f84\u5bb9\u7eb3\u81a8\u80c0\uff0c\u5c31\u53ef\u80fd\u5f62\u6210\u8d85\u538b\u95ee\u9898\u3002\u56e0\u6b64\uff0c\u9996\u8981\u7684\u5de5\u7a0b\u95ee\u9898\u5e76\u4e0d\u662f <strong>\u201c\u6211\u5e94\u8be5\u8d2d\u4e70\u54ea\u79cd\u70ed\u81a8\u80c0\u6cc4\u538b\u9600\uff1f\u201d<\/strong> \u800c\u662f <strong>\u201c\u8be5\u7ba1\u6bb5\u662f\u5426\u786e\u5b9e\u6784\u6210\u53ef\u4fe1\u7684\u70ed\u81a8\u80c0\u6cc4\u653e\u5de5\u51b5\uff1f\u201d<\/strong> <\/p>\n<p> \u9600\u95e8\u5173\u95ed\u672c\u8eab\u5e76\u4e0d\u80fd\u786e\u7acb\u5b8c\u6574\u7684\u6cc4\u653e\u5de5\u51b5\u3002\u7ba1\u9053\u5c3a\u5bf8\u4e0d\u80fd\u51b3\u5b9a\u6240\u9700\u6cc4\u653e\u91cf\u3002\u5e38\u89c4\u6db2\u4f53\u5de5\u51b5\u5e76\u4e0d\u80fd\u8bc1\u660e\u6d41\u4f53\u5728\u6574\u4e2a\u6cc4\u653e\u88c5\u7f6e\u4e2d\u59cb\u7ec8\u4fdd\u6301\u5355\u76f8\u3002\u5373\u4f7f\u5b89\u5168\u9600\u9009\u578b\u6b63\u786e\uff0c\u4ecd\u987b\u7ed3\u5408\u5176\u6392\u653e\u7ba1\u8def\u548c\u9884\u671f\u80cc\u538b\u8fdb\u884c\u590d\u6838\u3002. <\/p>\n<p class=\"z-decision-chain\"> \u786e\u5b9a\u5c01\u95ed\u8fb9\u754c \u2192 \u786e\u8ba4\u70ed\u81a8\u80c0\u5de5\u51b5 \u2192 \u786e\u5b9a\u6240\u9700\u6cc4\u653e\u8d1f\u8377 \u2192 \u786e\u5b9a\u538b\u529b\u57fa\u51c6 \u2192 \u6838\u5b9e\u6cc4\u653e\u6d41\u4f53\u72b6\u6001 \u2192 \u590d\u6838\u51fa\u53e3\u7cfb\u7edf \u2192 \u8bc4\u4f30\u5b89\u5168\u9600\u9009\u578b\u65b9\u6848\u4e0e\u8be2\u4ef7\u8d44\u6599\u3002. <\/p>\n<p> \u82f1\u56fd HSE \u5de5\u827a\u7ba1\u9053\u6307\u5357\u6307\u51fa\uff0c\u6db2\u4f53\u53ef\u80fd\u88ab\u5c01\u95ed\u5728\u5173\u95ed\u7684\u9600\u95e8\u4e4b\u95f4\uff0c\u6e29\u5ea6\u53d8\u5316\u968f\u540e\u4f1a\u5f15\u8d77\u70ed\u81a8\u80c0\u5e76\u5bfc\u81f4\u5b8c\u6574\u6027\u4e27\u5931\u3002\u8be5\u6307\u5357\u8fd8\u5f3a\u8c03\uff0c\u538b\u529b\u6cc4\u653e\u5e94\u57fa\u4e8e\u5b9e\u9645\u8fd0\u884c\u548c\u9694\u79bb\u5de5\u51b5\uff0c\u800c\u975e\u4ec5\u51ed\u662f\u5426\u5b89\u88c5\u4e86\u9600\u95e8\u6765\u5224\u65ad\u3002. <a href=\"https:\/\/www.hse.gov.uk\/comah\/sragtech\/techmeaspipework.htm\" target=\"_blank\" rel=\"noopener noreferrer\">HSE \u7ba1\u9053\u6307\u5357<\/a>. <\/p>\n<p> \u5982\u9700\u4e86\u89e3\u66f4\u5e7f\u6cdb\u7684\u7ba1\u9053\u8d85\u538b\u80cc\u666f\uff0c\u8bf7\u53c2\u9605 <a href=\"https:\/\/zobai.com\/zh\/applications\/pipelines\/\">ZOBAI \u7684\u7ba1\u9053\u6cc4\u653e\u5e94\u7528\u6307\u5357<\/a>. \u8be5\u9875\u9762\u6db5\u76d6\u591a\u79cd\u7ba1\u9053\u8d85\u538b\u5de5\u51b5\uff1b\u672c\u6587\u5219\u805a\u7126\u4e8e\u5c01\u95ed\u6db2\u4f53\u7ba1\u8def\u7684\u70ed\u81a8\u80c0\u95ee\u9898\u3002. <\/p>\n<section id=\"blocked-in-liquid-thermal-expansion-case\">\n<h2>\u5c01\u95ed\u6db2\u4f53\u7ba1\u8def\u4f55\u65f6\u6784\u6210\u70ed\u81a8\u80c0\u8d85\u538b\u5de5\u51b5\uff1f<\/h2>\n<p>\n  \u70ed\u81a8\u80c0\u5de5\u51b5\u7684\u8d77\u70b9\u662f <strong>\u771f\u5b9e\u5b58\u5728\u7684\u5c01\u95ed\u6db2\u4f53\u538b\u529b\u8fb9\u754c\uff0c<\/strong>,<br \/>\n  \u800c\u4e0d\u4ec5\u4ec5\u662f\u4f4e\u6d41\u91cf\u6216\u5355\u4e2a\u9600\u95e8\u5173\u95ed\u3002.\n<\/p>\n<ol>\n<li>\n    <strong>\u786e\u5b9a\u9694\u79bb\u8fb9\u754c\u3002.<\/strong><br \/>\n    \u8bc6\u522b\u53ef\u80fd\u5b58\u7559\u6db2\u4f53\u7684\u9600\u95e8\u3001\u8bbe\u5907\u63a5\u53e3\u6216\u5176\u4ed6\u9694\u79bb\u70b9\u3002.\n  <\/li>\n<li>\n    <strong>\u786e\u5b9a\u88ab\u5c01\u95ed\u7684\u4ecb\u8d28\u3002.<\/strong><br \/>\n    \u5224\u65ad\u8be5\u7ba1\u6bb5\u662f\u5426\u53ef\u80fd\u8fbe\u5230\u6ee1\u6db2\u72b6\u6001\uff0c\u6216\u4ee5\u5176\u4ed6\u65b9\u5f0f\u53d7\u5230\u8db3\u591f\u7ea6\u675f\uff0c<br \/>\n    \u4ece\u800c\u4f7f\u70ed\u81a8\u80c0\u6210\u4e3a\u9700\u8981\u8003\u8651\u7684\u56e0\u7d20\u3002.\n  <\/li>\n<li>\n    <strong>\u786e\u5b9a\u53ef\u4fe1\u7684\u6e29\u5ea6\u5347\u9ad8\u3002.<\/strong><br \/>\n    \u8003\u8651\u53ef\u80fd\u4f7f\u5c01\u95ed\u6db2\u4f53\u5347\u6e29\u7684\u76f8\u5173\u8fd0\u884c\u3001\u505c\u8f66\u3001\u5907\u7528\u6216\u73af\u5883\u6761\u4ef6\u3002<br \/>\n    \u5c01\u95ed\u6db2\u4f53\u3002.\n  <\/li>\n<li>\n    <strong>\u5c06\u8be5\u5de5\u51b5\u4e0e\u88ab\u4fdd\u62a4\u7684\u538b\u529b\u8fb9\u754c\u8fdb\u884c\u5bf9\u6bd4\u3002.<\/strong><br \/>\n    \u5224\u65ad\u7531\u6b64\u4ea7\u751f\u7684\u5de5\u51b5\u662f\u5426\u4f1a\u8d85\u51fa\u9002\u7528\u7684\u538b\u529b\u57fa\u51c6\uff0c\u8be5\u57fa\u51c6\u9488\u5bf9<br \/>\n    \u7ba1\u9053\u6216\u8bbe\u5907\u3002.\n  <\/li>\n<\/ol>\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\/thermal-expansion-relief-valve-img-01.webp\" alt=\"\u6db2\u4f53\u5145\u6ee1\u7684\u7ba1\u9053\u6bb5\u88ab\u9694\u79bb\u70b9\u5c01\u95ed\u5e76\u53ef\u80fd\u56e0\u6e29\u5ea6\u5347\u9ad8\u800c\u8d85\u538b\u7684\u793a\u610f\u56fe\u3002.\" title=\"Thermal Expansion Relief Valve for Blocked-In Liquid Lines - IMG-01\" width=\"1200\" height=\"900\" class=\"wp-image-56863\" decoding=\"async\" srcset=\"https:\/\/zobai.com\/wp-content\/uploads\/2026\/09\/thermal-expansion-relief-valve-img-01.webp 1200w, https:\/\/zobai.com\/wp-content\/uploads\/2026\/09\/thermal-expansion-relief-valve-img-01-300x225.webp 300w, https:\/\/zobai.com\/wp-content\/uploads\/2026\/09\/thermal-expansion-relief-valve-img-01-1024x768.webp 1024w, https:\/\/zobai.com\/wp-content\/uploads\/2026\/09\/thermal-expansion-relief-valve-img-01-768x576.webp 768w, https:\/\/zobai.com\/wp-content\/uploads\/2026\/09\/thermal-expansion-relief-valve-img-01-16x12.webp 16w, https:\/\/zobai.com\/wp-content\/uploads\/2026\/09\/thermal-expansion-relief-valve-img-01-400x300.webp 400w\" sizes=\"auto, (max-width: 1200px) 100vw, 1200px\" \/><figcaption>\u6db2\u4f53\u5145\u6ee1\u7684\u7ba1\u9053\u6bb5\u88ab\u9694\u79bb\u70b9\u5c01\u95ed\u5e76\u53ef\u80fd\u56e0\u6e29\u5ea6\u5347\u9ad8\u800c\u8d85\u538b\u7684\u793a\u610f\u56fe\u3002.<\/figcaption><\/figure>\n<p>\n  \u6db2\u4f53\u7684\u53ef\u538b\u7f29\u6027\u8fdc\u4f4e\u4e8e\u6c14\u4f53\u3002\u5f53\u9694\u79bb\u5bb9\u79ef\u5185\u57fa\u672c\u5145\u6ee1<br \/>\n  \u6db2\u4f53\u65f6\uff0c\u5347\u6e29\u4ea7\u751f\u7684\u989d\u5916\u6db2\u4f53\u4f53\u79ef\u53ef\u80fd\u56e0\u6b64\u8f6c\u5316\u4e3a<br \/>\n  \u6025\u5267\u7684\u538b\u529b\u5347\u9ad8\uff0c\u9664\u975e\u7cfb\u7edf\u5177\u5907\u8db3\u591f\u7684\u65b9\u5f0f\u6765\u5bb9\u7eb3\u6216\u6cc4\u653e\u8be5\u538b\u529b\u3002.\n<\/p>\n<p>\n  \u70ed\u91cf\u8f93\u5165\u56e0\u88c5\u7f6e\u800c\u5f02\u3002\u6839\u636e\u7cfb\u7edf\u7684\u4e0d\u540c\uff0c\u76f8\u5173\u6765\u6e90\u53ef\u80fd\u5305\u62ec<br \/>\n  \u73af\u5883\u6216\u65e5\u7167\u5347\u6e29\u3001\u4f34\u70ed\u3001\u5468\u56f4\u53d7\u70ed\u533a\u57df\u6216\u76f8\u90bb\u5de5\u827a<br \/>\n  \u8bbe\u5907\u3002\u5b58\u5728\u5176\u4e2d\u67d0\u4e00\u6765\u6e90\u5e76\u4e0d\u81ea\u52a8\u4f7f\u5176\u6210\u4e3a\u63a7\u5236<br \/>\n  \u5de5\u51b5\uff1b\u5fc5\u987b\u9488\u5bf9\u5b9e\u9645\u88c5\u7f6e\u786e\u5b9a\u53ef\u4fe1\u5de5\u51b5\u3002.\n<\/p>\n<blockquote>\n<p>\n    <strong>\u5c01\u95ed\u5e76\u4e0d\u53ea\u662f\u6307\u201c\u65e0\u6d41\u52a8\u201d\u3002\u201d<\/strong><br \/>\n    \u5b83\u662f\u6307\u7cfb\u7edf\u5728\u70ed\u81a8\u80c0\u53ef\u80fd\u5bf9\u8be5\u8fb9\u754c\u6784\u6210\u6311\u6218\u7684\u6761\u4ef6\u4e0b<br \/>\n    \u80fd\u591f\u5f62\u6210\u53d7\u7ea6\u675f\u7684\u6db2\u4f53\u538b\u529b\u8fb9\u754c\u3002.\n  <\/p>\n<\/blockquote>\n<p>\n  \u8fd9\u662f\u5728\u786e\u5b9a\u6cc4\u653e\u88c5\u7f6e\u5c3a\u5bf8\u6216\u9009\u578b\u4e4b\u524d\u9700\u8981\u786e\u7acb\u7684\u6761\u4ef6\u3002.\n<\/p>\n<\/section>\n<section id=\"dedicated-thermal-relief-valve-decision\">\n<h2>\u662f\u5426\u6bcf\u4e2a\u88ab\u9694\u79bb\u7684\u6db2\u4f53\u7ba1\u6bb5\u90fd\u9700\u8981\u4e13\u7528\u70ed\u81a8\u80c0\u6cc4\u538b\u9600\uff1f<\/h2>\n<p><strong>\u5e76\u975e\u81ea\u52a8\u5982\u6b64\u3002.<\/strong><\/p>\n<p>\n  \u8bc6\u522b\u51fa\u53ef\u4fe1\u7684\u70ed\u81a8\u80c0\u5de5\u51b5\uff0c\u5373\u53ef\u786e\u8ba4\u8d85\u538b\u98ce\u9669<br \/>\n  \u9700\u8981\u91c7\u53d6\u9002\u5f53\u7684\u5de5\u7a0b\u5e94\u5bf9\u63aa\u65bd\u3002\u8fd9\u5e76\u4e0d\u80fd\u4ec5\u51ed\u8be5\u5de5\u51b5\u5c31\u8bc1\u660e<br \/>\n  \u67d0\u4e00\u7279\u5b9a\u7684\u4e13\u7528\u70ed\u81a8\u80c0\u6cc4\u538b\u9600\u914d\u7f6e\u662f\u552f\u4e00\u53ef\u63a5\u53d7\u7684\u65b9\u6848\u3002.\n<\/p>\n<div class=\"z-table-wrap\"\n     role=\"region\"\n     aria-label=\"Difference between identifying the thermal expansion scenario and selecting a relief valve\"\n     tabindex=\"0\"><\/p>\n<table>\n<thead>\n<tr>\n<th scope=\"col\">\u5de5\u7a0b\u95ee\u9898<\/th>\n<th scope=\"col\">\u5b9e\u9645\u5df2\u786e\u7acb\u7684\u662f\u4ec0\u4e48\uff1f<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>\u6db2\u4f53\u662f\u5426\u53ef\u80fd\u88ab\u5c01\u95ed\u5e76\u5347\u6e29\uff1f<\/td>\n<td>\u5b58\u5728\u6f5c\u5728\u7684\u70ed\u81a8\u80c0\u5de5\u51b5\u3002.<\/td>\n<\/tr>\n<tr>\n<td>\u8be5\u5de5\u51b5\u662f\u5426\u4f1a\u5a01\u80c1\u53d7\u4fdd\u62a4\u7684\u627f\u538b\u8fb9\u754c\uff1f<\/td>\n<td>\u5fc5\u987b\u8bc4\u4f30\u8d85\u538b\u4fdd\u62a4\u63aa\u65bd\u3002.<\/td>\n<\/tr>\n<tr>\n<td>\u89e3\u51b3\u65b9\u6848\u662f\u5426\u5fc5\u987b\u91c7\u7528\u4e13\u7528\u70ed\u81a8\u80c0\u6cc4\u538b\u9600\uff1f<\/td>\n<td>\u8fd9\u53d6\u51b3\u4e8e\u6240\u91c7\u7528\u7684\u4fdd\u62a4\u7b56\u7565\u548c\u9879\u76ee\u4f9d\u636e\u3002.<\/td>\n<\/tr>\n<tr>\n<td>\u7279\u5b9a\u9600\u95e8\u662f\u5426\u9002\u7528\uff1f<\/td>\n<td>\u8fd9\u9700\u8981\u660e\u786e\u7684\u5de5\u51b5\u6761\u4ef6\u4ee5\u53ca\u9488\u5bf9\u8be5\u4ea7\u54c1\u7684\u5177\u4f53\u4f9d\u636e\u3002.<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<p>\n  \u6839\u636e\u7cfb\u7edf\u53ca\u9002\u7528\u7684\u5de5\u7a0b\u4f9d\u636e\uff0c\u4fdd\u62a4\u63aa\u65bd\u53ef\u91c7\u7528<br \/>\n  \u6cc4\u538b\u88c5\u7f6e\u6216\u5176\u4ed6\u5de5\u7a0b\u914d\u7f6e\uff0c\u4ee5\u9632\u6b62\u4ea7\u751f\u4e0d\u53ef\u63a5\u53d7\u7684<br \/>\n  \u538b\u529b\u3002\u9002\u7528\u4e8e\u67d0\u4e00\u5de5\u51b5\u6216\u67d0\u4e00\u53f8\u6cd5\u7ba1\u8f96\u533a\u7684\u65b9\u6848\uff0c\u4e0d\u5e94<br \/>\n  \u63a8\u5e7f\u81f3\u6240\u6709\u5de5\u827a\u7ba1\u7ebf\u3002.\n<\/p>\n<p>\n  API 521 \u6807\u51c6\u662f\u77f3\u6cb9\u3001,<br \/>\n  \u77f3\u5316\u3001LNG \u53ca\u76f8\u5173\u8bbe\u65bd\u7684\u7cfb\u7edf\u7ea7\u538b\u529b\u6cc4\u653e\u4e0e\u964d\u538b\u53c2\u8003\u4f9d\u636e\u3002\u5176\u8303\u56f4\u652f\u6301\u5728\u5c06\u67d0\u4e00\u4ea7\u54c1\u540d\u79f0\u4f5c\u4e3a\u8bbe\u8ba1\u51b3\u7b56\u4e4b\u524d\uff0c<br \/>\n  \u5bf9\u6cc4\u653e\u5de5\u51b5\u548c\u7cfb\u7edf\u8fdb\u884c\u8bc4\u4f30\u3002.<br \/>\n  <a href=\"https:\/\/www.api.org\/products-and-services\/standards\/important-standards-announcements\/standard521\" target=\"_blank\" rel=\"noopener noreferrer\">API 521 \u6807\u51c6\u4fe1\u606f<\/a>.\n<\/p>\n<p>\n  \u672f\u8bed\u4e5f\u53ef\u80fd\u5bf9\u91c7\u8d2d\u4ea7\u751f\u8bef\u5bfc\u3002. <strong>\u9759\u6c34\u6cc4\u653e\u9600<\/strong><br \/>\n  \u5728\u67d0\u4e9b\u884c\u4e1a\u4e2d\u7528\u4e8e\u4fdd\u62a4\u53ef\u80fd\u56e0\u622a\u65ad\u9600\u4e4b\u95f4\u79ef\u6db2\u800c\u8d85\u538b\u7684\u7ba1\u9053<br \/>\n  \u88c5\u7f6e\u3002\u8fd9\u79cd\u5b9e\u9645\u672f\u8bed\u91cd\u53e0\u5e76\u4e0d\u610f\u5473\u7740<br \/>\n  \u201c\u9759\u6c34\u538b\u6cc4\u538b\u9600\u201d\u4e0e\u201c\u70ed\u81a8\u80c0\u6cc4\u538b\u9600\u201d\u5728\u6240\u6709<br \/>\n  \u9002\u7528\u4e8e\u5404\u79cd\u6d41\u4f53\u3001\u89c4\u8303\u6216\u884c\u4e1a\u3002.\n<\/p>\n<p class=\"z-decision-chain\">\n  \u5de5\u51b5\u786e\u8ba4 \u2192 \u4fdd\u62a4\u7b56\u7565\u786e\u5b9a \u2192 \u6838\u67e5\u9002\u7528\u9879\u76ee\/\u89c4\u8303\u4f9d\u636e<br \/>\n  \u2192 \u9009\u5b9a\u5e76\u9a8c\u8bc1\u6cc4\u653e\u88c5\u7f6e\u3002.\n<\/p>\n<p>\n  \u5982\u9700\u4e86\u89e3\u66f4\u5168\u9762\u7684\u6807\u51c6\u80cc\u666f\uff0c\u8bf7\u53c2\u9605<br \/>\n  <a href=\"https:\/\/zobai.com\/zh\/standards\/api-521-pressure-relief-systems\/\"><br \/>\n    ZOBAI \u7684 API 521 \u538b\u529b\u6cc4\u653e\u7cfb\u7edf\u6307\u5357<br \/>\n  <\/a>.\n<\/p>\n<\/section>\n<section id=\"thermal-relief-rate-valve-capacity\">\n<h2>\u70ed\u81a8\u80c0\u6cc4\u653e\u91cf\u4e0e\u5b89\u5168\u9600\u6392\u91cf\u7531\u54ea\u4e9b\u56e0\u7d20\u51b3\u5b9a\uff1f<\/h2>\n<p>\n  \u70ed\u81a8\u80c0\u6cc4\u538b\u9600\u5e94\u6839\u636e<br \/>\n  <strong>\u6240\u9700\u6cc4\u653e\u8d1f\u8377<\/strong>, \u9009\u578b\uff0c\u800c\u4e0d\u662f\u6839\u636e\u7ba1\u9053\u76f4\u5f84\u6216\u4e60\u60ef\u6027\u7684<br \/>\n  \u201c\u5c0f\u578b\u70ed\u81a8\u80c0\u9600\u201d\u89c4\u683c\u3002.\n<\/p>\n<p>\n  \u5bf9\u4e8e\u5145\u6ee1\u6db2\u4f53\u7684\u70ed\u81a8\u80c0\u5de5\u51b5\uff0c\u6cc4\u653e\u8981\u6c42\u53d6\u51b3\u4e8e\u70ed<br \/>\n  \u6761\u4ef6\u4ee5\u53ca\u51b3\u5b9a\u6db2\u4f53\u968f\u6e29\u5ea6\u53d8\u5316\u54cd\u5e94\u7684\u6d41\u4f53\u7269\u6027<br \/>\n  \u786e\u5b9a\u6240\u9700\u6cc4\u653e\u6d41\u91cf\u540e\uff0c\u5b9e\u9645\u9600\u95e8\u5b9a\u5f84\u8fd8\u53d6\u51b3\u4e8e<br \/>\n  \u9002\u7528\u7684\u6cc4\u653e\u538b\u529b\u3001\u6e29\u5ea6\u3001\u51fa\u53e3\/\u80cc\u538b\u5de5\u51b5\u53ca<br \/>\n  \u6d41\u4f53\u72b6\u6001\u3002.\n<\/p>\n<p class=\"z-decision-chain\">\n  \u53ef\u4fe1\u70ed\u5de5\u51b5 \u2192 \u9002\u7528\u6d41\u4f53\u7269\u6027 \u2192 \u6240\u9700\u6cc4\u653e\u901f\u7387<br \/>\n  \u2192 \u6cc4\u653e\u538b\u529b\u4e0e\u51fa\u53e3\u5de5\u51b5 \u2192 \u9002\u7528\u5b9a\u5f84\u65b9\u6cd5<br \/>\n  \u2192 \u6240\u9700\u6d41\u901a\u9762\u79ef\/\u6392\u91cf \u2192 \u5019\u9009\u9600\u95e8\u6392\u91cf\u6821\u6838\u3002.\n<\/p>\n<figure class=\"wp-block-image size-full zobai-figure\" data-image-slot=\"IMG-02\"><img loading=\"lazy\" src=\"https:\/\/zobai.com\/wp-content\/uploads\/2026\/09\/thermal-expansion-relief-valve-img-02.webp\" alt=\"\u6d41\u7a0b\u56fe\u5c55\u793a\u5728\u6838\u7b97\u9600\u95e8\u6392\u91cf\u4e4b\u524d\uff0c\u7528\u4e8e\u786e\u5b9a\u70ed\u6cc4\u653e\u8d1f\u8377\u7684\u5de5\u827a\u53ca\u6d41\u4f53\u8f93\u5165\u6761\u4ef6\u3002.\" title=\"Thermal Expansion Relief Valve for Blocked-In Liquid Lines - IMG-02\" width=\"1200\" height=\"900\" class=\"wp-image-56864\" decoding=\"async\" srcset=\"https:\/\/zobai.com\/wp-content\/uploads\/2026\/09\/thermal-expansion-relief-valve-img-02.webp 1200w, https:\/\/zobai.com\/wp-content\/uploads\/2026\/09\/thermal-expansion-relief-valve-img-02-300x225.webp 300w, https:\/\/zobai.com\/wp-content\/uploads\/2026\/09\/thermal-expansion-relief-valve-img-02-1024x768.webp 1024w, https:\/\/zobai.com\/wp-content\/uploads\/2026\/09\/thermal-expansion-relief-valve-img-02-768x576.webp 768w, https:\/\/zobai.com\/wp-content\/uploads\/2026\/09\/thermal-expansion-relief-valve-img-02-16x12.webp 16w, https:\/\/zobai.com\/wp-content\/uploads\/2026\/09\/thermal-expansion-relief-valve-img-02-400x300.webp 400w\" sizes=\"auto, (max-width: 1200px) 100vw, 1200px\" \/><figcaption>\u6d41\u7a0b\u56fe\u5c55\u793a\u5728\u6838\u7b97\u9600\u95e8\u6392\u91cf\u4e4b\u524d\uff0c\u7528\u4e8e\u786e\u5b9a\u70ed\u6cc4\u653e\u8d1f\u8377\u7684\u5de5\u827a\u53ca\u6d41\u4f53\u8f93\u5165\u6761\u4ef6\u3002.<\/figcaption><\/figure>\n<p>\n  \u6709\u4e24\u79cd\u7b80\u5316\u505a\u6cd5\u5e94\u5f53\u907f\u514d\u3002. <strong>\u8fde\u63a5\u5c3a\u5bf8\u4e0d\u7b49\u4e8e\u6392\u91cf<\/strong>:<br \/>\n  \u9600\u95e8\u53ef\u80fd\u5728\u673a\u68b0\u4e0a\u9002\u914d\u7ba1\u7ebf\uff0c\u4f46\u4ecd\u4e0d\u5177\u5907\u8be5<br \/>\n  \u6cc4\u653e\u5de5\u51b5\u6240\u9700\u7684\u6392\u91cf\u3002\u6b64\u5916\uff0c <strong>\u201c\u70ed\u6cc4\u653e\u6d41\u91cf\u901a\u5e38\u76f8\u5bf9\u8f83\u5c0f\u201d\u5e76\u4e0d\u662f\u5b9a\u5f84<br \/>\n  \u65b9\u6cd5<\/strong>: \u5373\u4f7f\u662f\u8f83\u5c0f\u7684\u5de5\u51b5\uff0c\u4e5f\u5fc5\u987b\u5728\u5019\u9009\u9600\u95e8<br \/>\n  \u88ab\u63a5\u53d7\u4e4b\u524d\u4e88\u4ee5\u786e\u5b9a\u3002.\n<\/p>\n<p>\n  API 520 Part I \u4e13\u95e8\u6d89\u53ca\u5176\u8303\u56f4\u5185\u7684\u538b\u529b\u6cc4\u653e\u88c5\u7f6e\u5b9a\u5f84\u548c<br \/>\n  \u9009\u578b\u3002.<br \/>\n  <a href=\"https:\/\/www.api.org\/products-and-services\/standards\/important-standards-announcements\/520parti\" target=\"_blank\" rel=\"noopener noreferrer\">API 520 Part I \u4fe1\u606f<\/a>.\n<\/p>\n<p>\n  \u5173\u4e8e\u8be6\u7ec6\u7684\u4e00\u822c\u5b9a\u5f84\u5de5\u4f5c\u6d41\u7a0b\uff0c\u800c\u975e\u5728\u6b64\u91cd\u590d\uff0c\u8bf7\u53c2\u89c1<br \/>\n  <a href=\"https:\/\/zobai.com\/zh\/blog\/safety-valve-sizing-and-certified-relieving-capacity-guide\/\"><br \/>\n    ZOBAI \u7684\u5b89\u5168\u9600\u5b9a\u5f84\u4e0e\u8ba4\u8bc1\u6cc4\u653e\u80fd\u529b\u6307\u5357<br \/>\n  <\/a>.\n<\/p>\n<p>\u8be5\u70ed\u81a8\u80c0\u5de5\u51b5\u7684\u5b9e\u7528\u8f93\u5165\u5305\u62ec\uff1a<\/p>\n<ul>\n<li>\u53d7\u4fdd\u62a4\u7ba1\u6bb5\u53ca\u76f8\u5173\u5c01\u95ed\u5bb9\u79ef\uff1b;<\/li>\n<li>\u53ef\u4fe1\u7684\u70ed\u6761\u4ef6\u6216\u70ed\u8f93\u5165\uff1b;<\/li>\n<li>\u6d41\u4f53\u6807\u8bc6\u53ca\u9002\u7528\u8ba1\u7b97\u6240\u9700\u7684\u7269\u7406\u6027\u8d28\uff1b;<\/li>\n<li>\u6cc4\u653e\u538b\u529b\u548c\u6e29\u5ea6\uff1b;<\/li>\n<li>\u6240\u9700\u6cc4\u653e\u91cf\uff1b;<\/li>\n<li>\u9884\u671f\u80cc\u538b\uff1b\u4ee5\u53ca<\/li>\n<li>\u5b9a\u5f84\u65b9\u6cd5\u6240\u91c7\u7528\u7684\u6d41\u4f53\u72b6\u6001\u5047\u8bbe\u3002.<\/li>\n<\/ul>\n<p>\n  \u53ea\u6709\u5728\u786e\u5b9a\u6240\u9700\u6cc4\u653e\u5de5\u51b5\u540e\uff0c\u624d\u5e94\u5c06\u6240\u9009\u5b89\u5168\u9600\u7684\u6587\u6863\u5316<br \/>\n  \u6392\u91cf\u4e0e\u6240\u9700\u6cc4\u653e\u91cf\u8fdb\u884c\u5bf9\u6bd4\u3002.\n<\/p>\n<p><strong>\u70ed\u6cc4\u653e\u5e94\u6309\u6cc4\u653e\u5de5\u51b5\u786e\u5b9a\u89c4\u683c\uff0c\u800c\u975e\u7b80\u5355\u9009\u7528\u5c0f\u89c4\u683c\u3002.<\/strong><\/p>\n<\/section>\n<section id=\"thermal-relief-set-pressure-basis\">\n<h2>\u6574\u5b9a\u538b\u529b\u57fa\u51c6\u5e94\u5982\u4f55\u786e\u5b9a\uff1f<\/h2>\n<p>\n  \u6574\u5b9a\u538b\u529b\u5e94\u4f9d\u636e <strong>\u88ab\u4fdd\u62a4\u7684\u538b\u529b\u8fb9\u754c<\/strong>,<br \/>\n  \u786e\u5b9a\uff0c\u800c\u975e\u7167\u642c\u6b63\u5e38\u5de5\u4f5c\u538b\u529b\u6216\u6309\u901a\u7528\u767e\u5206\u6bd4\u89c4\u5219\u9009\u53d6\u3002.\n<\/p>\n<p>\n  \u8fd9\u79cd\u533a\u5206\u7b26\u5408\u516c\u8ba4\u7684\u6cc4\u653e\u88c5\u7f6e\u9009\u578b\u89c4\u8303\uff1a<br \/>\n  \u5de5\u4f5c\u538b\u529b\u3001\u6574\u5b9a\u538b\u529b\u3001\u6cc4\u653e\/\u8bbe\u8ba1\u6e29\u5ea6\u3001\u5141\u8bb8\u8d85\u538b\uff0c,<br \/>\n  \u80cc\u538b\u4e0e\u6240\u9700\u6392\u91cf\u4f5c\u4e3a\u4e24\u4e2a\u4e0d\u540c\u7684\u8f93\u5165\u53c2\u6570\u5904\u7406\uff0c\u800c\u975e<br \/>\n  \u53ef\u4e92\u6362\u7684\u6570\u503c\u3002.<br \/>\n  <a href=\"https:\/\/dam.bakerhughes.com\/m\/3b234d808f4b5dbd\/original\/BHCN-2478-TS-20201D-1020-English-pdf.pdf\" target=\"_blank\" rel=\"noopener noreferrer\"><br \/>\n    Baker Hughes \u6cc4\u538b\u9600\u6280\u672f\u89c4\u683c\u6307\u5357<br \/>\n  <\/a>.\n<\/p>\n<div class=\"z-table-wrap\"\n     role=\"region\"\n     aria-label=\"Pressure terms used when specifying a thermal expansion relief valve\"\n     tabindex=\"0\"><\/p>\n<table>\n<thead>\n<tr>\n<th scope=\"col\">\u538b\u529b\u672f\u8bed<\/th>\n<th scope=\"col\">\u5728\u70ed\u6cc4\u653e\u51b3\u7b56\u4e2d\u7684\u4f5c\u7528<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>\u5de5\u4f5c\u538b\u529b<\/td>\n<td>\u7cfb\u7edf\u6b63\u5e38\u8fd0\u884c\u65f6\u6240\u627f\u53d7\u7684\u538b\u529b\u3002.<\/td>\n<\/tr>\n<tr>\n<td>\u88ab\u4fdd\u62a4\u8bbe\u8ba1\/\u5141\u8bb8\u538b\u529b\u57fa\u51c6<\/td>\n<td>\u88ab\u4fdd\u62a4\u7ba1\u9053\u6216\u8bbe\u5907\u6240\u9002\u7528\u7684\u538b\u529b\u8fb9\u754c\u3002.<\/td>\n<\/tr>\n<tr>\n<td>\u6574\u5b9a\u538b\u529b<\/td>\n<td>\u6cc4\u653e\u88c5\u7f6e\u5f00\u59cb\u5176\u89c4\u5b9a\u5f00\u542f\u52a8\u4f5c\u65f6\u6240\u5bf9\u5e94\u7684\u6574\u5b9a\u538b\u529b\u3002.<\/td>\n<\/tr>\n<tr>\n<td>\u6cc4\u653e\u538b\u529b<\/td>\n<td>\u7528\u4e8e\u6cc4\u653e\u5b9a\u5f84\u6216\u6392\u91cf\u8bc4\u4f30\u7684\u538b\u529b\u5de5\u51b5\u3002.<\/td>\n<\/tr>\n<tr>\n<td>\u80cc\u538b<\/td>\n<td>\u4f5c\u7528\u4e8e\u9600\u95e8\u51fa\u53e3\u4fa7\u6216\u51fa\u53e3\u4e0b\u6e38\u7684\u538b\u529b\u3002.<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<p>\n  \u8fd9\u4e9b\u6570\u503c\u76f8\u4e92\u5173\u8054\uff0c\u4f46\u4e0d\u53ef\u4e92\u6362\u3002\u786e\u5b9a\u54ea\u4e9b\u7ba1\u9053\u548c<br \/>\n  \u90e8\u4ef6\u4f4d\u4e8e\u9694\u79bb\u8fb9\u754c\u4e4b\u5185\uff0c\u7136\u540e\u786e\u5b9a\u63a7\u5236\u538b\u529b\u57fa\u51c6<br \/>\n  under the applicable design code, equipment rules and project specification before<br \/>\n  assigning the valve set pressure.\n<\/p>\n<p>\n  Scope discipline matters here. A pressure rule written for a vessel should not automatically<br \/>\n  be transplanted into generic process piping, and a regulation written specifically for LPG,<br \/>\n  ammonia or another service should not be generalized to unrelated fluids or jurisdictions.\n<\/p>\n<p>\n  This article therefore does not create a universal rule such as<br \/>\n  <strong>\u201cset the thermal relief valve at a fixed percentage above operating pressure.\u201d<\/strong><br \/>\n  Where a numerical relationship is prescribed, it belongs to the applicable equipment,<br \/>\n  code, project and jurisdictional basis.\n<\/p>\n<p>\n  For an RFQ, set pressure should be treated as the result of a protected-system engineering<br \/>\n  decision, not merely as a field to complete on a vendor datasheet.\n<\/p>\n<\/section>\n<section id=\"relieving-fluid-state\">\n<h2>Why the Relieving Fluid State Must Be Checked, Not Assumed<\/h2>\n<p>\n  A line can be liquid-filled before the relief event without remaining a simple<br \/>\n  single-phase liquid system throughout the complete relieving path.\n<\/p>\n<p>\n  Relief-valve engineering guidance distinguishes straightforward liquid sizing from cases<br \/>\n  in which subcooled liquid can flash as pressure falls through the valve. That makes the<br \/>\n  relieving-state check a real sizing boundary rather than a semantic detail.<br \/>\n  <a href=\"https:\/\/www.leser.com\/-\/media\/files\/engineering\/leser_engineering.pdf\" target=\"_blank\" rel=\"noopener noreferrer\">LESER engineering guidance<\/a>.\n<\/p>\n<p>\n  As pressure changes through the valve and downstream piping, the relationship between fluid<br \/>\n  pressure and temperature can change. Under some conditions, the liquid remains adequately<br \/>\n  subcooled and a liquid-sizing basis remains appropriate. Under others, flashing or a more<br \/>\n  complex phase condition may need to be considered.\n<\/p>\n<figure class=\"wp-block-image size-full zobai-figure\" data-image-slot=\"IMG-03\"><img loading=\"lazy\" src=\"https:\/\/zobai.com\/wp-content\/uploads\/2026\/09\/thermal-expansion-relief-valve-img-03.webp\" alt=\"Concept diagram comparing an initially liquid condition with possible liquid-only or flashing conditions during relief.\" title=\"Thermal Expansion Relief Valve for Blocked-In Liquid Lines - IMG-03\" width=\"1200\" height=\"900\" class=\"wp-image-56865\" decoding=\"async\" srcset=\"https:\/\/zobai.com\/wp-content\/uploads\/2026\/09\/thermal-expansion-relief-valve-img-03.webp 1200w, https:\/\/zobai.com\/wp-content\/uploads\/2026\/09\/thermal-expansion-relief-valve-img-03-300x225.webp 300w, https:\/\/zobai.com\/wp-content\/uploads\/2026\/09\/thermal-expansion-relief-valve-img-03-1024x768.webp 1024w, https:\/\/zobai.com\/wp-content\/uploads\/2026\/09\/thermal-expansion-relief-valve-img-03-768x576.webp 768w, https:\/\/zobai.com\/wp-content\/uploads\/2026\/09\/thermal-expansion-relief-valve-img-03-16x12.webp 16w, https:\/\/zobai.com\/wp-content\/uploads\/2026\/09\/thermal-expansion-relief-valve-img-03-400x300.webp 400w\" sizes=\"auto, (max-width: 1200px) 100vw, 1200px\" \/><figcaption>Concept diagram comparing an initially liquid condition with possible liquid-only or flashing conditions during relief.<\/figcaption><\/figure>\n<blockquote>\n<p>\n    <strong><br \/>\n      At the relevant relieving pressure and temperature\u2014and as pressure falls through the<br \/>\n      valve and outlet system\u2014does the fluid remain in the phase assumed by the sizing method?<br \/>\n    <\/strong>\n  <\/p>\n<\/blockquote>\n<p>\n  If the assumed phase remains valid, the case can continue under the appropriate liquid-sizing<br \/>\n  methodology. If meaningful phase change occurs, the required inputs and sizing treatment can<br \/>\n  change. That does not mean every thermal-expansion case is two-phase; it means the phase<br \/>\n  assumption should be verified rather than inherited from the normal operating description.\n<\/p>\n<p>\n  A procurement description such as <strong>\u201cliquid service, thermal relief\u201d<\/strong><br \/>\n  therefore does not by itself prove the relieving-state assumption required for final sizing.\n<\/p>\n<p>\n  This article treats <strong>initial phase<\/strong> \u548c <strong>relieving phase<\/strong><br \/>\n  as related but separate engineering inputs.\n<\/p>\n<\/section>\n<section id=\"thermal-relief-discharge-back-pressure\">\n<h2>Why Discharge Routing and Back Pressure Are Part of the Relief Decision<\/h2>\n<p>\n  A correctly selected valve is not enough if the installed relief path cannot perform<br \/>\n  under the defined scenario.\n<\/p>\n<p class=\"z-decision-chain\">\n  Protected section \u2192 valve inlet \u2192 relief device \u2192 outlet piping \u2192 disposal or recovery destination.\n<\/p>\n<figure class=\"wp-block-image size-full zobai-figure\" data-image-slot=\"IMG-04\"><img loading=\"lazy\" src=\"https:\/\/zobai.com\/wp-content\/uploads\/2026\/09\/thermal-expansion-relief-valve-img-04.webp\" alt=\"Diagram showing the complete thermal relief path from the protected liquid section through the relief valve to the downstream destination and back-pressure source.\" title=\"Thermal Expansion Relief Valve for Blocked-In Liquid Lines - IMG-04\" width=\"1200\" height=\"900\" class=\"wp-image-56866\" decoding=\"async\" srcset=\"https:\/\/zobai.com\/wp-content\/uploads\/2026\/09\/thermal-expansion-relief-valve-img-04.webp 1200w, https:\/\/zobai.com\/wp-content\/uploads\/2026\/09\/thermal-expansion-relief-valve-img-04-300x225.webp 300w, https:\/\/zobai.com\/wp-content\/uploads\/2026\/09\/thermal-expansion-relief-valve-img-04-1024x768.webp 1024w, https:\/\/zobai.com\/wp-content\/uploads\/2026\/09\/thermal-expansion-relief-valve-img-04-768x576.webp 768w, https:\/\/zobai.com\/wp-content\/uploads\/2026\/09\/thermal-expansion-relief-valve-img-04-16x12.webp 16w, https:\/\/zobai.com\/wp-content\/uploads\/2026\/09\/thermal-expansion-relief-valve-img-04-400x300.webp 400w\" sizes=\"auto, (max-width: 1200px) 100vw, 1200px\" \/><figcaption>Diagram showing the complete thermal relief path from the protected liquid section through the relief valve to the downstream destination and back-pressure source.<\/figcaption><\/figure>\n<p>\n  The review should establish where the relieved liquid will go, whether that route remains<br \/>\n  available during the relief case, and what pressure the downstream system will impose on<br \/>\n  the valve.\n<\/p>\n<p>\n  Back pressure can influence relief-valve behavior and available capacity, depending on the<br \/>\n  valve design and system. Emerson\u2019s pressure-relief-valve engineering handbook treats back<br \/>\n  pressure as a factor that can affect opening or reseating behavior, stability and capacity,<br \/>\n  so it belongs in candidate verification rather than being left as a post-purchase piping detail.<br \/>\n  <a href=\"https:\/\/www.emerson.com\/documents\/automation\/pressure-relief-valve-engineering-handbook-cs-cz-4262398.pdf\" target=\"_blank\" rel=\"noopener noreferrer\"><br \/>\n    Emerson \u6cc4\u538b\u9600\u5de5\u7a0b\u624b\u518c<br \/>\n  <\/a>.\n<\/p>\n<p>\n  For a deeper treatment of that interface, see<br \/>\n  <a href=\"https:\/\/zobai.com\/zh\/engineering\/back-pressure-and-bellows\/\"><br \/>\n    ZOBAI\u2019s back-pressure and bellows engineering guide<br \/>\n  <\/a>.\n<\/p>\n<p>\n  The destination itself is service-dependent. A small expected thermal-relief rate does<br \/>\n  not prove that unrestricted atmospheric discharge is acceptable. Conversely, a closed<br \/>\n  return, drain or recovery system is not automatically suitable if it imposes unacceptable<br \/>\n  back pressure or can be isolated when relief is required.\n<\/p>\n<p>\n  ISO 23251 provides an international pressure-relief-system framework for petroleum,<br \/>\n  petrochemical and natural-gas industries. Its current 2019 edition explicitly supplements<br \/>\n  API 521 6th Edition, so project teams should confirm the adopted standard set rather than<br \/>\n  silently treating different editions as textually equivalent.<br \/>\n  <a href=\"https:\/\/www.iso.org\/standard\/75144.html\" target=\"_blank\" rel=\"noopener noreferrer\">ISO 23251 information<\/a>.\n<\/p>\n<blockquote>\n<p>\n    <strong><br \/>\n      Where can the relieved fluid go without compromising either safe disposal or the valve\u2019s<br \/>\n      ability to perform its relief function?<br \/>\n    <\/strong>\n  <\/p>\n<\/blockquote>\n<p>\n  Detailed flare design, closed-header hydraulics and valve-architecture thresholds belong<br \/>\n  to separate engineering work. This article only needs to establish that the outlet system<br \/>\n  forms part of the relief decision.\n<\/p>\n<\/section>\n<section id=\"thermal-relief-rfq-engineering-review\">\n<h2>What Information Belongs in a Thermal-Relief RFQ or Engineering Review?<\/h2>\n<p>\n  A technically useful RFQ should describe the <strong>protected system and relief duty<\/strong>,<br \/>\n  not simply request a valve by nominal size.\n<\/p>\n<p>\n  Separate the process inputs from the supplier verification:\n<\/p>\n<div class=\"z-table-wrap\"\n     role=\"region\"\n     aria-label=\"Thermal relief RFQ data split between the buyer or engineer and the valve supplier\"\n     tabindex=\"0\"><\/p>\n<table>\n<thead>\n<tr>\n<th scope=\"col\">Buyer \/ engineer should define or assign<\/th>\n<th scope=\"col\">Supplier \/ candidate should confirm<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Protected piping or equipment boundary<\/td>\n<td>Exact valve configuration offered<\/td>\n<\/tr>\n<tr>\n<td>Fluid and relevant composition<\/td>\n<td>Wetted-material, seat and seal suitability<\/td>\n<\/tr>\n<tr>\n<td>Normal fluid state<\/td>\n<td>Pressure-temperature suitability<\/td>\n<\/tr>\n<tr>\n<td>Operating pressure and temperature<\/td>\n<td>Available set-pressure capability<\/td>\n<\/tr>\n<tr>\n<td>Governing protected-pressure basis<\/td>\n<td>Documented capacity for the specified duty<\/td>\n<\/tr>\n<tr>\n<td>Credible thermal condition or heat source<\/td>\n<td>Selected flow area or valve size<\/td>\n<\/tr>\n<tr>\n<td>Required relieving rate, or responsibility for determining it<\/td>\n<td>Effect of specified back pressure on the candidate<\/td>\n<\/tr>\n<tr>\n<td>Relieving-phase assumption<\/td>\n<td>Connection and pressure-class suitability<\/td>\n<\/tr>\n<tr>\n<td>Expected back pressure<\/td>\n<td>Applicable inspection or test documentation<\/td>\n<\/tr>\n<tr>\n<td>Relief destination<\/td>\n<td>Requested conformity documentation, where applicable<\/td>\n<\/tr>\n<tr>\n<td>Applicable project code or specification<\/td>\n<td>Deviations, limitations and unresolved points<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<p>\n  <strong>Required relieving capacity is not the same as connection size.<\/strong><br \/>\n  One is a process-protection requirement; the other is primarily an installation characteristic.\n<\/p>\n<p>\n  <strong>Required capacity is also not the same as compliance evidence.<\/strong><br \/>\n  Capacity documentation addresses the flow-performance question under the applicable basis.<br \/>\n  Material certificates, inspection records or other project-required conformity evidence<br \/>\n  answer different procurement questions.\n<\/p>\n<p>\n  A supplier should not have to guess the relief scenario. If the protected pressure basis,<br \/>\n  thermal condition, required relieving rate, fluid state or expected back pressure remains<br \/>\n  undefined, those gaps should be resolved before a proposed valve is treated as an approved<br \/>\n  candidate.\n<\/p>\n<blockquote>\n<p>\n    <strong><br \/>\n      Can the proposed valve be traced back to a defined thermal-expansion duty, protected<br \/>\n      pressure boundary, relieving state and outlet condition\u2014and does the supplier evidence<br \/>\n      address each of those requirements?<br \/>\n    <\/strong>\n  <\/p>\n<\/blockquote>\n<p>\n  If not, the candidate is not ready for approval merely because a catalogue uses the words<br \/>\n  <strong>\u70ed\u6cc4\u653e<\/strong> \u6216 <strong>hydrostatic relief<\/strong>.\n<\/p>\n<aside class=\"z-cta\" aria-label=\"Engineering enquiry\">\n<p><strong>Have a blocked-in liquid relief case to review?<\/strong><\/p>\n<p>\n    Prepare the protected boundary, fluid, operating and relieving conditions, required relief<br \/>\n    duty, set-pressure basis, expected back pressure, discharge destination and applicable<br \/>\n    project requirements before requesting a valve candidate.\n  <\/p>\n<p>\n    <a href=\"https:\/\/zobai.com\/zh\/ask-an-engineer\/\"><br \/>\n      Submit the defined duty for engineering and RFQ review<br \/>\n    <\/a>\n  <\/p>\n<\/aside>\n<\/section>\n<\/article>","protected":false},"excerpt":{"rendered":"<p>\u4e86\u89e3\u5c01\u95ed\u6db2\u4f53\u5728\u4f55\u79cd\u60c5\u51b5\u4e0b\u5f62\u6210\u70ed\u81a8\u80c0\u6cc4\u653e\u5de5\u51b5\u3001\u6392\u91cf\u4e0e\u6574\u5b9a\u538b\u529b\u7531\u54ea\u4e9b\u56e0\u7d20\u51b3\u5b9a\uff0c\u4ee5\u53ca\u5728\u9009\u9600\u524d\u9700\u8981\u6838\u5b9e\u54ea\u4e9b\u6570\u636e\u3002.<\/p>","protected":false},"author":2,"featured_media":56863,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[74],"tags":[],"class_list":["post-56806","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-sizing-performance-engineering"],"_links":{"self":[{"href":"https:\/\/zobai.com\/zh\/wp-json\/wp\/v2\/posts\/56806","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/zobai.com\/zh\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/zobai.com\/zh\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/zobai.com\/zh\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/zobai.com\/zh\/wp-json\/wp\/v2\/comments?post=56806"}],"version-history":[{"count":2,"href":"https:\/\/zobai.com\/zh\/wp-json\/wp\/v2\/posts\/56806\/revisions"}],"predecessor-version":[{"id":56894,"href":"https:\/\/zobai.com\/zh\/wp-json\/wp\/v2\/posts\/56806\/revisions\/56894"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/zobai.com\/zh\/wp-json\/wp\/v2\/media\/56863"}],"wp:attachment":[{"href":"https:\/\/zobai.com\/zh\/wp-json\/wp\/v2\/media?parent=56806"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/zobai.com\/zh\/wp-json\/wp\/v2\/categories?post=56806"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/zobai.com\/zh\/wp-json\/wp\/v2\/tags?post=56806"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}