APISafety & Relief Devices

API 527

Seat Tightness of Pressure Relief Valves

International
Safety & Relief Devices

Reference profile

Designation
API 527
Title
Seat Tightness of Pressure Relief Valves
Issuing body
API
Current edition
[verify]
Status
Library record: published; official standard status [verify].
Category
Safety & Relief Devices
1

Overview

Describes methods of determining the seat tightness of metal- and soft-seated pressure relief valves, including those of conventional, bellows, and pilot-operated designs.

2

Scope & Applicability

Covers

  • Test Apparatus
  • Test Medium
  • Acceptance Criteria
  • Leakage Rates (Bubbles/min)

Does NOT cover (exclusions)

  • Exclusions are not documented in this library record. Confirm the official publication, neighbouring codes, the adopted edition, and jurisdictional boundaries before application.
3

Key Requirements

Lifecycle requirements

  • PRV Testing
  • Maintenance
  • Inspection
4

Technical Details

Describes methods of determining the seat tightness of metal- and soft-seated pressure relief valves, including those of conventional, bellows, and pilot-operated designs.

Components: Valve Seat, Valve Disc.

Where to find it in the codeRefer to the official table of contents and the sections cited by the project specification; section numbering can vary by edition.
5

Engineering Notes

  • Defines acceptable leakage (in bubbles per minute) for PRVs during shop testing.
6

Related Standards

  • API 526

    Companion or referenced standard; verify its exact relationship in the adopted edition.

  • API 576

    Companion or referenced standard; verify its exact relationship in the adopted edition.

7

Source, Edition & Status

Publisher
API
Edition Year
N/A
Industries
Petrochemical, Refinery, Chemical, Oil & Gas
Content Status
published
Last Reviewed
2026-07-01
Last Updated
2026-07-01
Verified By
Engineering Reviewer
Official Link
N/A

This paraphrased summary is a discovery aid. Do not reproduce or substitute it for the copyrighted official publication or jurisdictional requirements.