{"id":52603,"date":"2026-05-04T05:34:08","date_gmt":"2026-05-04T05:34:08","guid":{"rendered":"https:\/\/zobai.com\/?p=52603"},"modified":"2026-06-09T06:32:31","modified_gmt":"2026-06-09T06:32:31","slug":"safety-valve-set-pressure-overpressure-blowdown","status":"publish","type":"post","link":"https:\/\/zobai.com\/ru\/blog\/safety-valve-set-pressure-overpressure-blowdown\/","title":{"rendered":"\u0414\u0430\u0432\u043b\u0435\u043d\u0438\u0435 \u0441\u0440\u0430\u0431\u0430\u0442\u044b\u0432\u0430\u043d\u0438\u044f, \u043f\u0435\u0440\u0435\u043f\u0430\u0434 \u0434\u0430\u0432\u043b\u0435\u043d\u0438\u044f \u0438 \u0437\u0430\u043a\u0440\u044b\u0442\u0438\u0435 \u043f\u0440\u0435\u0434\u043e\u0445\u0440\u0430\u043d\u0438\u0442\u0435\u043b\u044c\u043d\u043e\u0433\u043e \u043a\u043b\u0430\u043f\u0430\u043d\u0430: \u043f\u043e\u0434\u0440\u043e\u0431\u043d\u043e\u0435 \u043e\u0431\u044a\u044f\u0441\u043d\u0435\u043d\u0438\u0435"},"content":{"rendered":"\n<!--\nSEO TITLE: Safety Valve Set Pressure, Overpressure & Blowdown\nH1 \/ POST TITLE: Safety Valve Set Pressure, Overpressure, Accumulation and Blowdown Explained\nMETA DESCRIPTION: Understand safety valve set pressure, relieving pressure, overpressure, accumulation, blowdown, reseating pressure and CDTP with formulas and troubleshooting guidance.\nCANONICAL: https:\/\/zobai.com\/blog\/safety-valve-set-pressure-overpressure-blowdown\/\nPRIMARY KEYWORD: safety valve set pressure\nSECONDARY KEYWORDS: safety valve overpressure; safety valve blowdown; set pressure vs relieving pressure; overpressure vs accumulation; safety valve reseating pressure; cold differential test pressure\nCATEGORY: Safety Valve Engineering\nTAGS: Set Pressure, Overpressure, Accumulation, Blowdown, Reseating Pressure\n\nPAGE OWNERSHIP:\n- This page owns safety-valve pressure terminology, formulas, operating margin, CDTP, reseating and pressure-related troubleshooting.\n- \/blog\/safety-valve-selection-guide\/ owns broad selection intent.\n- \/blog\/safety-valve-sizing-and-certified-relieving-capacity-guide\/ owns sizing and certified-capacity intent.\n- \/blog\/how-back-pressure-affects-safety-valve-performance\/ owns back-pressure education and troubleshooting.\n- \/standards\/api-527-seat-tightness-test\/ owns seat-tightness test requirements.\n- \/engineering\/safety-valve-installation-guide\/ owns inlet\/outlet piping and installation intent.\n\nIMPORTANT:\n1. 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.zobai-pressure-guide .toc ol{columns:1}\n  .zobai-pressure-guide .checklist{grid-template-columns:1fr}\n  .zobai-pressure-guide .cta{padding:26px 20px}\n}\n<\/style>\n\n<article class=\"zobai-pressure-guide\">\n\n<p class=\"lead\">Set pressure, relieving pressure, overpressure, accumulation, blowdown and reseating pressure describe different stages of safety-valve operation. Confusing them can lead to leakage during normal operation, incorrect capacity review, chatter, excessive pressure rise or poor reseating after a relief event.<\/p>\n\n<p>A valve can pass a workshop set-pressure test and still perform poorly in service when operating pressure is too close to set pressure, back pressure changes the installed behavior, inlet pressure loss is excessive or the valve was adjusted without the correct temperature and service-pressure corrections.<\/p>\n\n<div class=\"box summary\">\n<strong>Engineering takeaway:<\/strong> Set pressure defines the specified opening-response point, but complete pressure protection also depends on the operating margin, relieving pressure, allowable overpressure, equipment accumulation limit, blowdown, back pressure, inlet loss, calibration basis and valve condition.\n<\/div>\n\n<figure>\n<img decoding=\"async\" loading=\"eager\" src=\"https:\/\/zobai.com\/wp-content\/uploads\/2026\/05\/set-pressure-overpressure-accumulation-blowdown-diagram.webp\" alt=\"Safety valve set pressure, relieving pressure, overpressure, accumulation, blowdown and reseating pressure diagram\" title=\"Safety Valve Pressure Terms Diagram\">\n<figcaption>The terms use different reference pressures and should not be treated as interchangeable.<\/figcaption>\n<\/figure>\n\n<section id=\"quick-reference\">\n<h2>60-Second Safety Valve Pressure-Term Reference<\/h2>\n\n<div class=\"table-wrap\">\n<table>\n<thead>\n<tr>\n<th>Term<\/th>\n<th>Reference Point<\/th>\n<th>Practical Meaning<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td><strong>Operating pressure<\/strong><\/td>\n<td>Normal process condition<\/td>\n<td>The pressure at which the system normally operates.<\/td>\n<\/tr>\n<tr>\n<td><strong>Set pressure<\/strong><\/td>\n<td>Valve operating characteristic<\/td>\n<td>The inlet pressure at which the valve is set to display the specified opening characteristic under defined conditions.<\/td>\n<\/tr>\n<tr>\n<td><strong>Cold differential test pressure<\/strong><\/td>\n<td>Test-stand adjustment<\/td>\n<td>The test pressure used to account for specified service effects such as temperature or back pressure when applicable.<\/td>\n<\/tr>\n<tr>\n<td><strong>Relieving pressure<\/strong><\/td>\n<td>Capacity condition<\/td>\n<td>The pressure condition used to determine or verify relieving capacity.<\/td>\n<\/tr>\n<tr>\n<td><strong>Overpressure<\/strong><\/td>\n<td>Set pressure<\/td>\n<td>The pressure increase above set pressure during relief.<\/td>\n<\/tr>\n<tr>\n<td><strong>MAWP \/ allowable equipment limit<\/strong><\/td>\n<td>Protected equipment<\/td>\n<td>The approved pressure boundary used by the applicable equipment design basis.<\/td>\n<\/tr>\n<tr>\n<td><strong>Accumulation<\/strong><\/td>\n<td>MAWP or applicable allowable limit<\/td>\n<td>The pressure increase above the protected equipment limit during relief.<\/td>\n<\/tr>\n<tr>\n<td><strong>Reseating pressure<\/strong><\/td>\n<td>Valve closing behavior<\/td>\n<td>The inlet pressure at which the valve closes after relieving.<\/td>\n<\/tr>\n<tr>\n<td><strong>Blowdown<\/strong><\/td>\n<td>Set pressure and reseating pressure<\/td>\n<td>The difference between set pressure and reseating pressure.<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n\n<div class=\"box warning\">\n<strong>Definition warning:<\/strong> The exact test indication used to establish set pressure can differ by valve type and applicable standard. A generic phrase such as \u201cfirst visible opening\u201d should not replace the specified test method.\n<\/div>\n<\/section>\n\n<nav class=\"toc\" aria-label=\"Table of contents\">\n<strong>Table of Contents<\/strong>\n<ol>\n<li><a href=\"#scope\">Scope and page ownership<\/a><\/li>\n<li><a href=\"#set-pressure\">Set pressure<\/a><\/li>\n<li><a href=\"#operating-margin\">Operating pressure margin<\/a><\/li>\n<li><a href=\"#cdtp\">Cold differential test pressure<\/a><\/li>\n<li><a href=\"#relieving-pressure\">Relieving pressure<\/a><\/li>\n<li><a href=\"#overpressure\">Overpressure<\/a><\/li>\n<li><a href=\"#accumulation\">Accumulation<\/a><\/li>\n<li><a href=\"#blowdown\">Blowdown and reseating<\/a><\/li>\n<li><a href=\"#formulas\">Pressure-term formulas<\/a><\/li>\n<li><a href=\"#worked-example\">Worked example<\/a><\/li>\n<li><a href=\"#back-pressure\">Back pressure interaction<\/a><\/li>\n<li><a href=\"#calibration\">Calibration and field adjustment<\/a><\/li>\n<li><a href=\"#troubleshooting\">Troubleshooting matrix<\/a><\/li>\n<li><a href=\"#hold-points\">Mandatory hold points<\/a><\/li>\n<li><a href=\"#review-workflow\">Eight-step review workflow<\/a><\/li>\n<li><a href=\"#rfq-data\">RFQ and maintenance records<\/a><\/li>\n<li><a href=\"#standards\">Standards and references<\/a><\/li>\n<li><a href=\"#faq\">FAQ<\/a><\/li>\n<\/ol>\n<\/nav>\n\n<section id=\"scope\">\n<h2>What This Guide Covers<\/h2>\n\n<p>This page explains the pressure relationships around a reclosing safety or pressure-relief valve. It is the site&#8217;s main page for set pressure, overpressure, accumulation, blowdown, reseating pressure and cold differential test pressure.<\/p>\n\n<p>It does not replace:<\/p>\n\n<ul>\n<li>the governing relief-scenario calculation;<\/li>\n<li>the capacity and orifice sizing method;<\/li>\n<li>the applicable equipment code or jurisdictional requirement;<\/li>\n<li>the manufacturer&#8217;s set-pressure and blowdown procedures;<\/li>\n<li>the installed back-pressure and piping analysis.<\/li>\n<\/ul>\n\n<p>For the broader decision process, use the <a href=\"\/blog\/safety-valve-selection-guide\/\">Safety Valve Selection Guide<\/a>. For capacity, use the <a href=\"\/blog\/safety-valve-sizing-and-certified-relieving-capacity-guide\/\">Safety Valve Sizing and Certified Capacity Guide<\/a>.<\/p>\n<\/section>\n\n<section id=\"set-pressure\">\n<h2>What Is Safety Valve Set Pressure?<\/h2>\n\n<p><strong>Set pressure<\/strong> is the inlet pressure at which the valve is adjusted to demonstrate the specified operating characteristic under defined test conditions. In practical terms, it establishes when the pressure-relief device begins its required opening response.<\/p>\n\n<p>Set pressure is normally identified on the approved datasheet, valve nameplate and calibration record. It should be selected from the protected equipment&#8217;s design basis, MAWP or other applicable allowable pressure, operating conditions, relief arrangement and code requirements.<\/p>\n\n<div class=\"grid\">\n<div class=\"card\">\n<h3>Set Pressure Does Confirm<\/h3>\n<p>The required opening-response setting under the specified test basis.<\/p>\n<\/div>\n<div class=\"card\">\n<h3>Set Pressure Does Not Confirm<\/h3>\n<p>Required capacity, stable full lift, acceptable back pressure, correct blowdown or seat tightness in service.<\/p>\n<\/div>\n<\/div>\n\n<h3>Why Set Pressure Should Not Be Changed Casually<\/h3>\n\n<p>Increasing set pressure to stop leakage can reduce or invalidate the intended protection of the equipment. Leakage may instead be caused by insufficient operating margin, damaged seating surfaces, contamination, corrosion, thermal distortion, piping loads, back-pressure fluctuations or poor calibration practice.<\/p>\n\n<div class=\"box critical\">\n<strong>Do not tighten the adjusting screw as a troubleshooting shortcut.<\/strong> Any set-pressure change should follow the approved engineering, calibration, sealing, tagging and documentation process.\n<\/div>\n<\/section>\n\n<section id=\"operating-margin\">\n<h2>Operating Pressure Margin Below Set Pressure<\/h2>\n\n<p><strong>Operating pressure<\/strong> is the normal pressure of the process. It is not a relief allowance. When normal or maximum operating pressure remains too close to set pressure, a valve may simmer, weep, leak or cycle during routine process fluctuations.<\/p>\n\n<figure>\n<img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/zobai.com\/wp-content\/uploads\/2026\/05\/operating-pressure-margin-below-set-pressure.webp\" alt=\"Operating pressure margin below safety valve set pressure\" title=\"Operating Pressure Margin Below Set Pressure\">\n<figcaption>The required margin is design- and service-specific; there is no universal percentage for every valve.<\/figcaption>\n<\/figure>\n\n<p>The appropriate margin depends on:<\/p>\n\n<ul>\n<li>conventional, balanced or pilot-operated design;<\/li>\n<li>metal or soft seat;<\/li>\n<li>process pressure fluctuation and pulsation;<\/li>\n<li>gas, steam, liquid or two-phase service;<\/li>\n<li>temperature and thermal cycling;<\/li>\n<li>superimposed back pressure;<\/li>\n<li>seat condition and leakage requirement;<\/li>\n<li>manufacturer guidance and the applicable code.<\/li>\n<\/ul>\n\n<p>A pilot-operated valve may support closer operation in suitable clean service, while a conventional spring-loaded valve may require a larger practical margin. This is a design decision, not a reason to apply one percentage to every application.<\/p>\n<\/section>\n\n<section id=\"cdtp\">\n<h2>Cold Differential Test Pressure and Test-Stand Adjustment<\/h2>\n\n<p><strong>Cold differential test pressure (CDTP)<\/strong> is a test-stand adjustment value used when the valve&#8217;s cold test condition differs from the intended service condition. Depending on the valve, applicable standard and manufacturer procedure, the adjustment may account for effects such as service temperature or constant superimposed back pressure.<\/p>\n\n<p>CDTP is important because a valve can be calibrated in a workshop at ambient temperature and without the installed downstream pressure. The workshop setting therefore may need a defined correction so the valve performs at the required set pressure in service.<\/p>\n\n<div class=\"flow\">Required in-service set pressure \u2192 identify service corrections \u2192 establish approved test pressure \u2192 calibrate and document \u2192 verify installed basis<\/div>\n\n<p>The calibration record should state:<\/p>\n\n<ul>\n<li>valve tag, model and serial number;<\/li>\n<li>required in-service set pressure;<\/li>\n<li>test pressure or CDTP used;<\/li>\n<li>test medium and test temperature;<\/li>\n<li>specified back-pressure or temperature correction;<\/li>\n<li>acceptance tolerance and observed result;<\/li>\n<li>seal, tag and technician or organization identification.<\/li>\n<\/ul>\n\n<div class=\"box warning\">\n<strong>Do not invent a CDTP correction.<\/strong> Use the applicable standard, approved datasheet and manufacturer procedure. Back pressure does not affect every valve design in the same way.\n<\/div>\n<\/section>\n\n<section id=\"relieving-pressure\">\n<h2>Set Pressure vs Relieving Pressure<\/h2>\n\n<p><strong>Set pressure<\/strong> defines the specified opening-response point. <strong>Relieving pressure<\/strong> is the pressure condition used for capacity determination or verification during the relief event.<\/p>\n\n<p>A valve may begin its opening response at set pressure but require additional pressure rise to reach the lift and flow associated with its rated or certified capacity. This is why a set-pressure certificate does not prove that the selected valve has enough capacity.<\/p>\n\n<div class=\"grid\">\n<div class=\"card\">\n<h3>Set Pressure Question<\/h3>\n<p>At what inlet pressure should the valve display the specified opening characteristic?<\/p>\n<\/div>\n<div class=\"card\">\n<h3>Relieving Pressure Question<\/h3>\n<p>At what pressure condition is the required or certified relieving flow evaluated?<\/p>\n<\/div>\n<\/div>\n\n<p>When approving sizing, compare the required relief load with manufacturer-certified capacity at the correct pressure, temperature, fluid and downstream basis.<\/p>\n<\/section>\n\n<section id=\"overpressure\">\n<h2>What Is Safety Valve Overpressure?<\/h2>\n\n<p><strong>Overpressure<\/strong> is the pressure increase above set pressure during a relief event. It is commonly expressed as a percentage of set pressure.<\/p>\n\n<div class=\"formula\">Overpressure (%) = [(Relieving Pressure \u2212 Set Pressure) \u00f7 Set Pressure] \u00d7 100<\/div>\n\n<p>Overpressure is connected to valve performance because the valve generally develops additional lift and flow as pressure rises above set pressure. The amount permitted or used in sizing depends on the applicable code, relief scenario, valve design and project basis.<\/p>\n\n<p>Overpressure should not be treated as routine operating space. It belongs to the emergency relief condition.<\/p>\n\n<h3>Why a Valve Can Open but Still Not Protect the System<\/h3>\n\n<p>If the system pressure continues to rise after the valve opens, possible causes include:<\/p>\n\n<ul>\n<li>required capacity greater than the selected valve&#8217;s certified capacity;<\/li>\n<li>wrong relieving-pressure assumption;<\/li>\n<li>incorrect fluid phase or properties;<\/li>\n<li>insufficient lift or unstable valve motion;<\/li>\n<li>excessive inlet pressure loss;<\/li>\n<li>excessive built-up back pressure;<\/li>\n<li>a relief scenario that was missed or underestimated.<\/li>\n<\/ul>\n<\/section>\n\n<section id=\"accumulation\">\n<h2>What Is Accumulation?<\/h2>\n\n<p><strong>Accumulation<\/strong> is the pressure increase above the protected equipment&#8217;s MAWP or other applicable allowable pressure limit during a relief event. It describes the pressure experienced by the equipment, not simply the valve&#8217;s pressure rise above set pressure.<\/p>\n\n<div class=\"formula\">Accumulation (%) = [(Maximum System Pressure During Relief \u2212 MAWP) \u00f7 MAWP] \u00d7 100<\/div>\n\n<p>Overpressure and accumulation may have the same numerical value only when set pressure equals the reference equipment limit used in the calculation. When set pressure is below MAWP, they are different.<\/p>\n\n<div class=\"table-wrap\">\n<table>\n<thead>\n<tr>\n<th>Term<\/th>\n<th>Reference<\/th>\n<th>Engineering Purpose<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Overpressure<\/td>\n<td>Valve set pressure<\/td>\n<td>Connects the valve&#8217;s pressure rise to its relieving behavior and capacity basis.<\/td>\n<\/tr>\n<tr>\n<td>Accumulation<\/td>\n<td>Equipment MAWP or applicable allowable limit<\/td>\n<td>Checks the maximum pressure experienced by the protected equipment.<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n\n<div class=\"box warning\">\n<strong>Do not copy an accumulation allowance from another project.<\/strong> The permitted value depends on the equipment code, relief scenario, number and arrangement of relief devices, jurisdiction and project specification.\n<\/div>\n<\/section>\n\n<section id=\"blowdown\">\n<h2>What Is Blowdown and Reseating Pressure?<\/h2>\n\n<p><strong>Reseating pressure<\/strong> is the inlet pressure at which the valve closes after relieving. <strong>Blowdown<\/strong> is the difference between set pressure and reseating pressure, commonly expressed as a percentage of set pressure.<\/p>\n\n<div class=\"formula\">Blowdown (%) = [(Set Pressure \u2212 Reseating Pressure) \u00f7 Set Pressure] \u00d7 100<\/div>\n\n<figure>\n<img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/zobai.com\/wp-content\/uploads\/2026\/05\/blowdown-and-reseating-pressure-diagram.webp\" alt=\"Safety valve blowdown and reseating pressure relationship\" title=\"Blowdown and Reseating Pressure\">\n<figcaption>Blowdown describes how far pressure falls below set pressure before the valve closes.<\/figcaption>\n<\/figure>\n\n<p>If blowdown is too large for the process, pressure may fall farther than necessary before closure. If it is too narrow for the process and installed conditions, the valve may cycle or fail to reseat cleanly.<\/p>\n\n<p>Reseating behavior can also be affected by:<\/p>\n\n<ul>\n<li>back pressure and outlet pressure fluctuation;<\/li>\n<li>inlet pressure loss;<\/li>\n<li>valve oversizing and low lift;<\/li>\n<li>disc, nozzle and guide condition;<\/li>\n<li>spring and adjustment condition;<\/li>\n<li>fluid phase and two-phase discharge;<\/li>\n<li>process pressure control and pulsation.<\/li>\n<\/ul>\n<\/section>\n\n<section id=\"formulas\">\n<h2>Pressure-Term Formula Summary<\/h2>\n\n<div class=\"table-wrap\">\n<table>\n<thead>\n<tr>\n<th>Calculation<\/th>\n<th>Formula<\/th>\n<th>Reference Pressure<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Overpressure<\/td>\n<td>(P<sub>relieving<\/sub> \u2212 P<sub>set<\/sub>) \u00f7 P<sub>set<\/sub> \u00d7 100<\/td>\n<td>Set pressure<\/td>\n<\/tr>\n<tr>\n<td>Accumulation<\/td>\n<td>(P<sub>maximum<\/sub> \u2212 MAWP) \u00f7 MAWP \u00d7 100<\/td>\n<td>Protected equipment limit<\/td>\n<\/tr>\n<tr>\n<td>Blowdown<\/td>\n<td>(P<sub>set<\/sub> \u2212 P<sub>reseat<\/sub>) \u00f7 P<sub>set<\/sub> \u00d7 100<\/td>\n<td>Set pressure<\/td>\n<\/tr>\n<tr>\n<td>Operating margin<\/td>\n<td>(P<sub>set<\/sub> \u2212 P<sub>operating<\/sub>) \u00f7 P<sub>set<\/sub> \u00d7 100<\/td>\n<td>Set pressure; use only as a descriptive margin unless the governing procedure defines it<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n\n<p>Use consistent units and the pressure basis required by the applicable calculation procedure. Do not mix gauge and absolute pressure values within one formula or combine data from different relief scenarios.<\/p>\n<\/section>\n\n<section id=\"worked-example\">\n<h2>Illustrative Example: Why Overpressure and Accumulation Differ<\/h2>\n\n<div class=\"case\">\n<span class=\"label\">Illustrative calculation \u2014 not a code allowance<\/span>\n\n<div class=\"table-wrap\">\n<table>\n<tbody>\n<tr><th>Equipment MAWP<\/th><td>10.0 barg<\/td><\/tr>\n<tr><th>Valve set pressure<\/th><td>9.5 barg<\/td><\/tr>\n<tr><th>Maximum pressure during relief<\/th><td>10.5 barg<\/td><\/tr>\n<tr><th>Reseating pressure<\/th><td>8.8 barg<\/td><\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n\n<h3>Overpressure<\/h3>\n<p>(10.5 \u2212 9.5) \u00f7 9.5 \u00d7 100 = <strong>10.5%<\/strong> approximately.<\/p>\n\n<h3>Accumulation<\/h3>\n<p>(10.5 \u2212 10.0) \u00f7 10.0 \u00d7 100 = <strong>5.0%<\/strong>.<\/p>\n\n<h3>Blowdown<\/h3>\n<p>(9.5 \u2212 8.8) \u00f7 9.5 \u00d7 100 = <strong>7.4%<\/strong> approximately.<\/p>\n\n<p><strong>Lesson:<\/strong> The same maximum relief pressure produces different overpressure and accumulation values because the reference pressures are different.<\/p>\n<\/div>\n<\/section>\n\n<section id=\"back-pressure\">\n<h2>How Back Pressure Interacts with Set Pressure and Blowdown<\/h2>\n\n<p>Back pressure is outlet-side pressure acting on the valve. It may exist before opening or be generated by discharge flow. Depending on the design, it can affect opening response, lift, capacity, blowdown and reseating.<\/p>\n\n<p>A conventional spring-loaded valve, balanced bellows valve and pilot-operated valve should not be assumed to respond identically. Constant superimposed back pressure may be considered in an approved test adjustment for some designs, while variable or built-up back pressure requires an installed-system review.<\/p>\n\n<p>Use the <a href=\"\/blog\/how-back-pressure-affects-safety-valve-performance\/\">Safety Valve Back Pressure Guide<\/a> for superimposed, built-up and total back-pressure analysis.<\/p>\n\n<div class=\"box critical\">\n<strong>A correct bench set pressure does not validate the outlet system.<\/strong> A valve can pass calibration and still chatter or reseat poorly because of the installed discharge piping.\n<\/div>\n<\/section>\n\n<section id=\"calibration\">\n<h2>Calibration, Sealing and Field Adjustment<\/h2>\n\n<p>Set-pressure verification should be performed using an approved procedure, suitable test equipment, the correct test medium and traceable instrumentation. The final record should identify the physical valve and the accepted adjustment.<\/p>\n\n<h3>Calibration Record Checklist<\/h3>\n\n<div class=\"checklist\">\n<div class=\"check\">Valve tag, model and serial number<\/div>\n<div class=\"check\">Nameplate set pressure<\/div>\n<div class=\"check\">Required in-service set pressure<\/div>\n<div class=\"check\">CDTP or test pressure where applicable<\/div>\n<div class=\"check\">Test medium and temperature<\/div>\n<div class=\"check\">Specified back-pressure correction<\/div>\n<div class=\"check\">Observed opening characteristic<\/div>\n<div class=\"check\">Reseating or blowdown result where tested<\/div>\n<div class=\"check\">Seat-tightness result when specified<\/div>\n<div class=\"check\">Instrument identification and calibration status<\/div>\n<div class=\"check\">Final seal and tag condition<\/div>\n<div class=\"check\">Technician, organization and approval date<\/div>\n<\/div>\n\n<p>For seat leakage testing, use the <a href=\"\/standards\/api-527-seat-tightness-test\/\">API 527 Seat Tightness Test Guide<\/a>. For repaired valves, the applicable owner, jurisdiction and repair authorization route should be followed.<\/p>\n\n<h3>Why Field Adjustment Is High Risk<\/h3>\n\n<p>Turning an adjusting screw changes only one part of the system. It does not correct an undersized valve, unstable outlet system, damaged seat, wrong fluid assumption or excessive operating pressure. Uncontrolled adjustment also breaks traceability between the valve, nameplate and calibration record.<\/p>\n<\/section>\n\n<section id=\"troubleshooting\">\n<h2>Pressure-Related Safety Valve Troubleshooting Matrix<\/h2>\n\n<figure>\n<img decoding=\"async\" loading=\"lazy\" src=\"https:\/\/zobai.com\/wp-content\/uploads\/2026\/05\/common-pressure-related-safety-valve-problems.webp\" alt=\"Pressure-related safety valve problems including leakage, chatter, insufficient relief and poor reseating\" title=\"Common Safety Valve Pressure Problems\">\n<figcaption>Observed symptoms should be traced to the pressure relationship and installed system, not only to the spring or seat.<\/figcaption>\n<\/figure>\n\n<div class=\"table-wrap\">\n<table>\n<thead>\n<tr>\n<th>Observed Symptom<\/th>\n<th>Possible Pressure-Related Causes<\/th>\n<th>Recommended Review<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Leaks or simmers before set pressure<\/td>\n<td>Operating pressure too close to set pressure, pressure pulsation, superimposed back pressure<\/td>\n<td>Operating margin, pressure trend, seat condition, piping load and calibration<\/td>\n<\/tr>\n<tr>\n<td>Opens earlier or later than expected<\/td>\n<td>Wrong test basis, CDTP error, temperature effect, constant back pressure, set drift<\/td>\n<td>Datasheet, test procedure, service correction and calibration record<\/td>\n<\/tr>\n<tr>\n<td>Chatters near set pressure<\/td>\n<td>Inlet loss, oversized valve, process instability, built-up back pressure, unsuitable blowdown<\/td>\n<td>Inlet\/outlet calculation, sizing, process trend and valve design<\/td>\n<\/tr>\n<tr>\n<td>Opens but system pressure continues rising<\/td>\n<td>Insufficient certified capacity, wrong relieving pressure, missed relief case, reduced lift<\/td>\n<td>Required load, orifice, certified capacity, fluid phase and back pressure<\/td>\n<\/tr>\n<tr>\n<td>Does not reseat cleanly<\/td>\n<td>Narrow or unsuitable blowdown, changing back pressure, damaged guide or seat, process pressure remains high<\/td>\n<td>Reseating trend, outlet pressure, internals and operating control<\/td>\n<\/tr>\n<tr>\n<td>Set point shifts after repair<\/td>\n<td>Incorrect assembly, spring or seat changes, wrong test correction, poor calibration control<\/td>\n<td>Repair record, parts, CDTP, test equipment, seal and tag<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n\n<p>For leakage after discharge, see <a href=\"\/blog\/why-safety-valves-leak-after-popping\/\">Why Safety Valves Leak After Popping<\/a>. For inlet and outlet piping, use the <a href=\"\/engineering\/safety-valve-installation-guide\/\">Safety Valve Installation Guide<\/a>.<\/p>\n<\/section>\n\n<section id=\"hold-points\">\n<h2>When Engineering Approval Must Be Held<\/h2>\n\n<div class=\"grid\">\n<div class=\"card\"><h3>Unknown MAWP or Code Basis<\/h3><p>The set pressure and accumulation limit cannot be approved without the protected equipment basis.<\/p><\/div>\n<div class=\"card\"><h3>Unknown Required Capacity<\/h3><p>A correct opening setting does not prove adequate pressure protection.<\/p><\/div>\n<div class=\"card\"><h3>Unclear Pressure References<\/h3><p>Gauge, absolute and different scenario values are being mixed.<\/p><\/div>\n<div class=\"card\"><h3>Unresolved Back Pressure<\/h3><p>The installed set response, capacity and reseating behavior may differ from the test stand.<\/p><\/div>\n<div class=\"card\"><h3>Unapproved Set-Pressure Change<\/h3><p>The valve nameplate and equipment protection basis would no longer agree.<\/p><\/div>\n<div class=\"card\"><h3>Missing CDTP Basis<\/h3><p>Temperature or constant back-pressure corrections have not been documented.<\/p><\/div>\n<div class=\"card\"><h3>Repeated Chatter or Leakage<\/h3><p>The root cause may be system-level rather than a calibration-only problem.<\/p><\/div>\n<div class=\"card\"><h3>Calibration and Nameplate Conflict<\/h3><p>The physical valve cannot be traced to the approved setting and record.<\/p><\/div>\n<\/div>\n<\/section>\n\n<section id=\"review-workflow\">\n<h2>Eight-Step Pressure-Term Review Workflow<\/h2>\n\n<ol class=\"steps\">\n<li><strong>Confirm the protected equipment limit.<\/strong><br>Identify MAWP, design basis, equipment code and jurisdiction.<\/li>\n<li><strong>Confirm operating pressure and fluctuations.<\/strong><br>Review normal, maximum and transient process pressure.<\/li>\n<li><strong>Approve the set pressure.<\/strong><br>Connect the valve setting to the protected equipment and relief arrangement.<\/li>\n<li><strong>Establish the relieving pressure and capacity basis.<\/strong><br>Use the approved relief scenario and applicable overpressure basis.<\/li>\n<li><strong>Check accumulation separately.<\/strong><br>Compare maximum system pressure with the equipment limit.<\/li>\n<li><strong>Review blowdown and reseating needs.<\/strong><br>Confirm that the process can fall far enough for stable closure.<\/li>\n<li><strong>Evaluate service corrections and installation.<\/strong><br>Review CDTP, temperature, back pressure, inlet loss and outlet piping.<\/li>\n<li><strong>Document calibration and approval.<\/strong><br>Align datasheet, nameplate, test record, seal, tag and maintenance system.<\/li>\n<\/ol>\n<\/section>\n\n<section id=\"rfq-data\">\n<h2>Pressure Data to Include in an RFQ or Repair Order<\/h2>\n\n<div class=\"table-wrap\">\n<table>\n<thead>\n<tr>\n<th>Data Item<\/th>\n<th>Why It Is Required<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr><td>Protected equipment and tag<\/td><td>Defines the pressure boundary and records link.<\/td><\/tr>\n<tr><td>MAWP \/ design pressure<\/td><td>Provides the equipment reference for set pressure and accumulation.<\/td><\/tr>\n<tr><td>Normal and maximum operating pressure<\/td><td>Shows the practical margin below set pressure.<\/td><\/tr>\n<tr><td>Required set pressure<\/td><td>Defines the valve&#8217;s approved opening-response setting.<\/td><\/tr>\n<tr><td>Relief scenario and required capacity<\/td><td>Connects the setting to the pressure-protection duty.<\/td><\/tr>\n<tr><td>Relieving pressure and temperature<\/td><td>Provides the capacity and material basis.<\/td><\/tr>\n<tr><td>Superimposed and built-up back pressure<\/td><td>Supports valve-type, CDTP and installed-performance review.<\/td><\/tr>\n<tr><td>Required blowdown or reseating behavior<\/td><td>Supports stable process recovery where specified.<\/td><\/tr>\n<tr><td>Test medium and test basis<\/td><td>Prevents inconsistent workshop calibration.<\/td><\/tr>\n<tr><td>Seat-tightness requirement<\/td><td>Defines the leakage test and acceptance record.<\/td><\/tr>\n<tr><td>Certificate, seal and tagging requirements<\/td><td>Preserves traceability from calibration to installation.<\/td><\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n\n<p>Use the <a href=\"\/blog\/safety-valve-procurement-checklist\/\">Safety Valve Procurement Checklist<\/a> for the full RFQ and supplier-document package.<\/p>\n<\/section>\n\n<section id=\"standards\">\n<h2>Standards and Authoritative References<\/h2>\n\n<p>The exact allowable values and test methods depend on the equipment, application, code edition and jurisdiction. The following references should be connected to a specific engineering decision.<\/p>\n\n<div class=\"table-wrap\">\n<table>\n<thead>\n<tr>\n<th>Reference<\/th>\n<th>Role in This Topic<\/th>\n<th>Link<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>ASME BPVC Section XIII<\/td>\n<td>Current ASME rules for overpressure protection of boilers, pressure vessels and piping systems<\/td>\n<td><a href=\"https:\/\/www.asme.org\/codes-standards\/find-codes-standards\/bpvc-xiii-bpvc-section-xiii-rules-overpressure-protection\" target=\"_blank\" rel=\"noopener noreferrer\">ASME official page<\/a><\/td>\n<\/tr>\n<tr>\n<td>API 520 Part I<\/td>\n<td>Sizing and selection, including the relationship between set, relieving conditions and capacity<\/td>\n<td><a href=\"https:\/\/www.api.org\/products-and-services\/standards\/important-standards-announcements\/520parti\" target=\"_blank\" rel=\"noopener noreferrer\">API official page<\/a><\/td>\n<\/tr>\n<tr>\n<td>API 520 Part II<\/td>\n<td>Installation analysis, including inlet and outlet conditions that affect stable operation<\/td>\n<td><a href=\"https:\/\/www.api.org\/products-and-services\/standards\/important-standards-announcements\/520part-ii\" target=\"_blank\" rel=\"noopener noreferrer\">API official page<\/a><\/td>\n<\/tr>\n<tr>\n<td>API 527<\/td>\n<td>Seat-tightness test methods and report requirements; not a sizing or set-pressure selection standard<\/td>\n<td><a href=\"\/standards\/api-527-seat-tightness-test\/\">ZOBAI API 527 Guide<\/a><\/td>\n<\/tr>\n<tr>\n<td>NBIC Part 4<\/td>\n<td>Installation, in-service inspection and repair guidance for pressure-relief devices where NBIC applies<\/td>\n<td><a href=\"https:\/\/www.nationalboard.org\/OrderTheNBIC.aspx\" target=\"_blank\" rel=\"noopener noreferrer\">National Board official page<\/a><\/td>\n<\/tr>\n<tr>\n<td>ZOBAI ASME Guide<\/td>\n<td>Procurement-oriented overview of ASME pressure-relief requirements and documentation<\/td>\n<td><a href=\"\/standards\/asme-safety-valve-standards\/\">ASME Safety Valve Standards<\/a><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n\n<div class=\"box warning\">\n<strong>Standards notice:<\/strong> A web article does not replace the official copyrighted standard, the required edition, the protected equipment design documents, manufacturer instructions or the responsible engineer&#8217;s approval.\n<\/div>\n<\/section>\n\n<aside class=\"author\">\n<h2>Engineering Review Note<\/h2>\n<p>This guide supports pressure-term interpretation, preliminary troubleshooting and RFQ preparation. Final values should be established from the actual equipment code, approved relief calculation, valve design, installed conditions, manufacturer procedures and traceable calibration records.<\/p>\n<p><strong>Publication requirement:<\/strong> Add a verified author, technical reviewer and last technical review date. Do not publish invented credentials or unverified field-experience claims.<\/p>\n<\/aside>\n\n<section class=\"related\">\n<h2>Related Safety Valve Engineering Resources<\/h2>\n<ul>\n<li><a href=\"\/blog\/safety-valve-selection-guide\/\">Safety Valve Selection Guide<\/a><\/li>\n<li><a href=\"\/blog\/safety-valve-sizing-and-certified-relieving-capacity-guide\/\">Safety Valve Sizing and Certified Capacity<\/a><\/li>\n<li><a href=\"\/blog\/how-back-pressure-affects-safety-valve-performance\/\">Safety Valve Back Pressure Guide<\/a><\/li>\n<li><a href=\"\/engineering\/safety-valve-installation-guide\/\">Safety Valve Installation Guide<\/a><\/li>\n<li><a href=\"\/standards\/api-527-seat-tightness-test\/\">API 527 Seat Tightness Test Guide<\/a><\/li>\n<li><a href=\"\/blog\/why-safety-valves-leak-after-popping\/\">Why Safety Valves Leak After Popping<\/a><\/li>\n<li><a href=\"\/blog\/safety-valve-procurement-checklist\/\">Safety Valve Procurement Checklist<\/a><\/li>\n<li><a href=\"\/resources\/safety-valve-certificates\/\">Safety Valve Certificates and Test Reports<\/a><\/li>\n<\/ul>\n<\/section>\n\n<section id=\"faq\">\n<h2>FAQ About Set Pressure, Overpressure and Blowdown<\/h2>\n\n<div class=\"faq\">\n<h3>What is safety valve set pressure?<\/h3>\n<p>It is the inlet pressure at which the valve is adjusted to demonstrate the specified opening characteristic under defined test conditions. It establishes the required response point but does not prove capacity or stable reseating.<\/p>\n<\/div>\n\n<div class=\"faq\">\n<h3>What is the difference between set pressure and relieving pressure?<\/h3>\n<p>Set pressure defines the specified opening-response point. Relieving pressure is the pressure condition used to determine or verify relieving capacity.<\/p>\n<\/div>\n\n<div class=\"faq\">\n<h3>What is safety valve overpressure?<\/h3>\n<p>Overpressure is the pressure increase above set pressure during relief, commonly expressed as a percentage of set pressure.<\/p>\n<\/div>\n\n<div class=\"faq\">\n<h3>What is the difference between overpressure and accumulation?<\/h3>\n<p>Overpressure is referenced to valve set pressure. Accumulation is referenced to the protected equipment&#8217;s MAWP or applicable allowable pressure limit.<\/p>\n<\/div>\n\n<div class=\"faq\">\n<h3>What is safety valve blowdown?<\/h3>\n<p>Blowdown is the difference between set pressure and reseating pressure, commonly expressed as a percentage of set pressure.<\/p>\n<\/div>\n\n<div class=\"faq\">\n<h3>What is cold differential test pressure?<\/h3>\n<p>CDTP is an approved test-stand adjustment pressure used when service conditions such as temperature or specified constant back pressure require correction from the cold test condition.<\/p>\n<\/div>\n\n<div class=\"faq\">\n<h3>Can set pressure be increased to stop leakage?<\/h3>\n<p>It should not be increased as an informal fix. The leakage cause should be diagnosed, and any approved setting change must be recalibrated, sealed, tagged and documented.<\/p>\n<\/div>\n\n<div class=\"faq\">\n<h3>Why does a valve chatter near set pressure?<\/h3>\n<p>Possible causes include excessive inlet loss, valve oversizing, process instability, built-up back pressure, outlet-system resistance or unsuitable blowdown behavior.<\/p>\n<\/div>\n\n<div class=\"faq\">\n<h3>Why can a valve pass calibration but fail in service?<\/h3>\n<p>The test stand may not reproduce service temperature, back pressure, inlet loss, outlet resistance, process pulsation or fluid conditions.<\/p>\n<\/div>\n\n<div class=\"faq\">\n<h3>Is there one required operating margin below set pressure?<\/h3>\n<p>No. The required margin depends on valve design, seat, medium, pressure fluctuation, temperature, back pressure, applicable code and manufacturer guidance.<\/p>\n<\/div>\n<\/section>\n\n<section class=\"cta\">\n<h2>Need a Set-Pressure or Calibration Review?<\/h2>\n<p>Send the protected equipment, MAWP, operating pressure, required set pressure, relief scenario, relieving conditions, back pressure, valve nameplate and calibration record for a technical review.<\/p>\n<a href=\"\/ask-an-engineer\/\">Upload Valve Data<\/a>\n<a href=\"\/contacts\/\">Request a Safety Valve Quote<\/a>\n<\/section>\n\n<\/article>\n\n<script type=\"application\/ld+json\">\n{\n  \"@context\":\"https:\/\/schema.org\",\n  \"@graph\":[\n    {\n      \"@type\":\"TechArticle\",\n      \"@id\":\"https:\/\/zobai.com\/blog\/safety-valve-set-pressure-overpressure-blowdown\/#article\",\n      \"mainEntityOfPage\":{\n        \"@type\":\"WebPage\",\n        \"@id\":\"https:\/\/zobai.com\/blog\/safety-valve-set-pressure-overpressure-blowdown\/\"\n      },\n      \"headline\":\"Safety Valve Set Pressure, Overpressure, Accumulation and Blowdown Explained\",\n      \"description\":\"Understand safety valve set pressure, relieving pressure, overpressure, accumulation, blowdown, reseating pressure and CDTP with formulas and troubleshooting guidance.\",\n      \"image\":[\n        \"https:\/\/zobai.com\/wp-content\/uploads\/2026\/05\/set-pressure-overpressure-accumulation-blowdown-diagram.webp\",\n        \"https:\/\/zobai.com\/wp-content\/uploads\/2026\/05\/operating-pressure-margin-below-set-pressure.webp\",\n        \"https:\/\/zobai.com\/wp-content\/uploads\/2026\/05\/blowdown-and-reseating-pressure-diagram.webp\",\n        \"https:\/\/zobai.com\/wp-content\/uploads\/2026\/05\/common-pressure-related-safety-valve-problems.webp\"\n      ],\n      \"author\":{\n        \"@type\":\"Organization\",\n        \"name\":\"ZOBAI Valve\",\n        \"url\":\"https:\/\/zobai.com\/\"\n      },\n      \"publisher\":{\n        \"@type\":\"Organization\",\n        \"name\":\"ZOBAI Valve\",\n        \"url\":\"https:\/\/zobai.com\/\"\n      },\n      \"datePublished\":\"2026-05-04\",\n      \"dateModified\":\"2026-06-09\",\n      \"keywords\":[\n        \"safety valve set pressure\",\n        \"safety valve overpressure\",\n        \"safety valve accumulation\",\n        \"safety valve blowdown\",\n        \"reseating pressure\",\n        \"cold differential test pressure\"\n      ],\n      \"about\":[\n        {\"@type\":\"Thing\",\"name\":\"Safety valve set pressure\"},\n        {\"@type\":\"Thing\",\"name\":\"Pressure relief valve overpressure\"},\n        {\"@type\":\"Thing\",\"name\":\"Safety valve blowdown\"}\n      ]\n    },\n    {\n      \"@type\":\"BreadcrumbList\",\n      \"@id\":\"https:\/\/zobai.com\/blog\/safety-valve-set-pressure-overpressure-blowdown\/#breadcrumb\",\n      \"itemListElement\":[\n        {\n          \"@type\":\"ListItem\",\n          \"position\":1,\n          \"name\":\"Home\",\n          \"item\":\"https:\/\/zobai.com\/\"\n        },\n        {\n          \"@type\":\"ListItem\",\n          \"position\":2,\n          \"name\":\"Safety Valve Engineering\",\n          \"item\":\"https:\/\/zobai.com\/knowledge-center\/\"\n        },\n        {\n          \"@type\":\"ListItem\",\n          \"position\":3,\n          \"name\":\"Safety Valve Set Pressure, Overpressure and Blowdown\",\n          \"item\":\"https:\/\/zobai.com\/blog\/safety-valve-set-pressure-overpressure-blowdown\/\"\n        }\n      ]\n    },\n    {\n      \"@type\":\"FAQPage\",\n      \"@id\":\"https:\/\/zobai.com\/blog\/safety-valve-set-pressure-overpressure-blowdown\/#faq\",\n      \"mainEntity\":[\n        {\n          \"@type\":\"Question\",\n          \"name\":\"What is safety valve set pressure?\",\n          \"acceptedAnswer\":{\n            \"@type\":\"Answer\",\n            \"text\":\"It is the inlet pressure at which the valve is adjusted to demonstrate the specified opening characteristic under defined test conditions. It establishes the required response point but does not prove capacity or stable reseating.\"\n          }\n        },\n        {\n          \"@type\":\"Question\",\n          \"name\":\"What is the difference between set pressure and relieving pressure?\",\n          \"acceptedAnswer\":{\n            \"@type\":\"Answer\",\n            \"text\":\"Set pressure defines the specified opening-response point. Relieving pressure is the pressure condition used to determine or verify relieving capacity.\"\n          }\n        },\n        {\n          \"@type\":\"Question\",\n          \"name\":\"What is safety valve overpressure?\",\n          \"acceptedAnswer\":{\n            \"@type\":\"Answer\",\n            \"text\":\"Overpressure is the pressure increase above set pressure during relief, commonly expressed as a percentage of set pressure.\"\n          }\n        },\n        {\n          \"@type\":\"Question\",\n          \"name\":\"What is the difference between overpressure and accumulation?\",\n          \"acceptedAnswer\":{\n            \"@type\":\"Answer\",\n            \"text\":\"Overpressure is referenced to valve set pressure. Accumulation is referenced to the protected equipment's MAWP or applicable allowable pressure limit.\"\n          }\n        },\n        {\n          \"@type\":\"Question\",\n          \"name\":\"What is safety valve blowdown?\",\n          \"acceptedAnswer\":{\n            \"@type\":\"Answer\",\n            \"text\":\"Blowdown is the difference between set pressure and reseating pressure, commonly expressed as a percentage of set pressure.\"\n          }\n        },\n        {\n          \"@type\":\"Question\",\n          \"name\":\"What is cold differential test pressure?\",\n          \"acceptedAnswer\":{\n            \"@type\":\"Answer\",\n            \"text\":\"CDTP is an approved test-stand adjustment pressure used when service conditions such as temperature or specified constant back pressure require correction from the cold test condition.\"\n          }\n        },\n        {\n          \"@type\":\"Question\",\n          \"name\":\"Can set pressure be increased to stop leakage?\",\n          \"acceptedAnswer\":{\n            \"@type\":\"Answer\",\n            \"text\":\"It should not be increased as an informal fix. The leakage cause should be diagnosed, and any approved setting change must be recalibrated, sealed, tagged and documented.\"\n          }\n        },\n        {\n          \"@type\":\"Question\",\n          \"name\":\"Why does a valve chatter near set pressure?\",\n          \"acceptedAnswer\":{\n            \"@type\":\"Answer\",\n            \"text\":\"Possible causes include excessive inlet loss, valve oversizing, process instability, built-up back pressure, outlet-system resistance or unsuitable blowdown behavior.\"\n          }\n        },\n        {\n          \"@type\":\"Question\",\n          \"name\":\"Why can a valve pass calibration but fail in service?\",\n          \"acceptedAnswer\":{\n            \"@type\":\"Answer\",\n            \"text\":\"The test stand may not reproduce service temperature, back pressure, inlet loss, outlet resistance, process pulsation or fluid conditions.\"\n          }\n        },\n        {\n          \"@type\":\"Question\",\n          \"name\":\"Is there one required operating margin below set pressure?\",\n          \"acceptedAnswer\":{\n            \"@type\":\"Answer\",\n            \"text\":\"No. The required margin depends on valve design, seat, medium, pressure fluctuation, temperature, back pressure, applicable code and manufacturer guidance.\"\n          }\n        }\n      ]\n    }\n  ]\n}\n<\/script>\n","protected":false},"excerpt":{"rendered":"<p>Set pressure, relieving pressure, overpressure, accumulation, blowdown and reseating pressure describe different stages of safety-valve operation. Confusing them can lead to leakage during normal operation, incorrect capacity review, chatter, excessive pressure rise or poor reseating after a relief event. A valve can pass a workshop set-pressure test and still perform poorly in service when operating&#8230;<\/p>","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-52603","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/zobai.com\/ru\/wp-json\/wp\/v2\/posts\/52603","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/zobai.com\/ru\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/zobai.com\/ru\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/zobai.com\/ru\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/zobai.com\/ru\/wp-json\/wp\/v2\/comments?post=52603"}],"version-history":[{"count":3,"href":"https:\/\/zobai.com\/ru\/wp-json\/wp\/v2\/posts\/52603\/revisions"}],"predecessor-version":[{"id":54904,"href":"https:\/\/zobai.com\/ru\/wp-json\/wp\/v2\/posts\/52603\/revisions\/54904"}],"wp:attachment":[{"href":"https:\/\/zobai.com\/ru\/wp-json\/wp\/v2\/media?parent=52603"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/zobai.com\/ru\/wp-json\/wp\/v2\/categories?post=52603"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/zobai.com\/ru\/wp-json\/wp\/v2\/tags?post=52603"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}