GB/T 5744-2023
Marine pneumatic quick closing valve (English Version)
- Standard No.
- GB/T 5744-2023
- Language
- Chinese, Available in English version
- Release Date
- 2023
- Published By
- General Administration of Quality Supervision, Inspection and Quarantine of the People‘s Republic of China
- Latest
- GB/T 5744-2023
- Replace
- GB/T 5744-2008
- Scope
- This document specifies the classification and marking, technical requirements, test methods, inspection rules, packaging and storage of marine pneumatic quick-closing valves (hereinafter referred to as quick-closing valves) with flange connection dimensions in accordance with CB/T 4196 and GB/T2501. This document is applicable to the design, manufacture and acceptance of quick-closing valves for ship piping systems.
- Introduction
Core changes in the standard revision
Revision items 2008 version 2023 version Technical impact Product type 3.1 4.1 Added AS/BS/CS/DS types, expanded to 6 types Nominal parameters 3.2 4.2 Pressure range adjusted to PN6-25, DN15-300 Cylinder test None 5.2.2/6.2.2 Added 1.5 times the air pressure strength test requirement Seal design Undifferentiated 4.3.6-4.3.7 A/B type hard seal vs CS/DS type soft seal
Analysis of key technical requirements
Structural design innovation
Emergency closing mechanism: Type A/B is kept open by the cylinder piston rod limit. In an emergency, the spring drives the valve disc to close within 0.3 seconds; Type CS/DS adopts a melting point class=instrument>98±5℃ fusible plug, high temperature melting triggers automatic shutdown.
Material specification upgrade
Components A/B type materials CS/DS type materials Valve body ZG230-450C ZG275-485/stainless steel Sealing surface 20Cr13 cladding PTFE+022Cr17Ni12Mo2 Low temperature working conditions Impact energy ≥27J(-29℃)
Implementation suggestions
- Give priority to matching CB/T 4196 or GB/T 2501 flange standards when selecting
- DS-type fuse valves with manual functions should be used for LNG pipelines
- Three test rods must be kept for each batch of castings
- Type inspection must include vibration test (GB/T 19845)
Typical application cases
A certain LNG carrier uses DS25250 type quick-closing valves in the engine room pipeline to achieve: ① pneumatic control under normal working conditions ② 98℃ fuse protection in case of fire ③ manual emergency intervention triple protection mechanism.
GB/T 5744-2023 Referenced Document
- CB/T 4196 Marine pipe flanges-connection dimensions and mating face
- CB/T 4299-2013 Marine castings of carbon and carbon-manganese steel
- CB/T 4456-2017 Low pressure pipe threaded joint
- GB/T 1176-2013 Casting copper and copper alloys
- GB/T 1184-1996 Geometrical tolerancing--Geometrical tolerance for features without individual tolerance indications
- GB/T 1220-2007 Stainless steel bars
- GB/T 1222-2016 Spring steels
- GB/T 12224 General requirements for industrial steel valves
- GB/T 12229-2005 General Purpose industrial valves.Specification of carbon steel castings
- GB/T 12230-2005 General purpose industrial valves.Specification of stainless steel castings
- GB/T 150.4-2011 Pressure vessels - Part 4: Fabrication,inspection and testing,and acceptance
- GB/T 1804-2000 General tolerances Tolerances for linear and angular dimensions without individual tolerance indications
- GB/T 1958 Geometrical Product Specifications(GPS)—Geometrical tolerance—Verification
- GB/T 19845-2005 Mechanical vibration.Vibration testing requirements for shipboard equipment and machinery components
- GB/T 229 Metallic materials—Charpy pendulum impact test method
- GB/T 2501 Connection dimensions and mating face of marine flanges
- GB/T 3032 Marks for marine piping valves and fittings
- GB/T 4423-2020 Copper and copper alloy cold-drawn rod and bar
- GB/T 600 General technical specifications for ship pipeline valves
- GB/T 699-2015 Quality carbon structure steels
- HG/T 2579-2008 Rubber Compounds of O-Rings used for Hydraulic fluid power System
- QB/T 4041-2010 Polytetrafluoroethylene rod
- YB/T 5318-2010 Alloy steel wires for spring
GB/T 5744-2023 history
- 2023 GB/T 5744-2023 Marine pneumatic quick closing valve
- 2008 GB/T 5744-2008 Marine quick-closing valves
- 1993 GB/T 5744-1993 Quick shutting valve for marine use