GB/T 12243-2005: Spring loaded safety valves

Delivery: 9 seconds. Download (and Email) true-PDF + Invoice.
Get Quotation: Click GB/T 12243-2005 (Self-service in 1-minute)
Newer / historical versions: GB/T 12243-2005

Preview True-PDF

Scope

This standard specifies the design, material, structure, performance, test and inspection,
marking, lead sealing, and delivery of spring loaded safety valves.
This standard is applicable to steam boilers of which the set-pressure is 0.1 MPa~42.0
MPa, the runner diameter is greater than or equal to 8mm; pressure vessels and pipe
safety valves.
2  Normative References
The articles contained in the following documents have become part of this standard when
they are quoted herein. For the dated documents so quoted, all the modifications
(excluding corrections) or revisions made thereafter shall not be applicable to this
Standard. For the undated documents so quoted, the latest editions shall be applicable to
this Standard.
GB/T 1239.2 “Cold Coiled Helical Compressions Springs - Technical Specifications”
GB/T 1239.4 “Hot Coiled Helical Springs - Technical Specifications”
GB/T 1239.6 “Design of Helical Springs”
GB/T 9440 “Malleable Iron Castings”
GB/T 12220 “General Purpose Industrial Valves - Marking” (GB/T 12220-1989, idt ISO
5209. 1977)
GB/T 12224 “General Requirements for Industrial Steel Valves”
GB/T 12225 “General Purpose Industrial Valves - Specification of Copper Alloy
Castings”
GB/T 12227 “General Purpose Industrial Valves - Specification of Spheroidal Graphite
Iron Castings”
GB/T 12228 “General Purpose Industrial Valves - Specifications of Carbon Steel
Forgings”
GB/T 12229 “General Purpose Industrial Valves - Specification of Carbon Steel
Castings”
GB/T 12230 “General Purpose Industrial Valves - Specifications of Austenitic Steel
Castings”
GB/T 12241 “Safety Valve - General Requirements” (GB/T 12241-2005, ISO
4126-1.1991, MOD)
GB/T 12242 “Performance Test Code Pressure Relief Devices”
JB/T 7928 “General Purpose Industrial Valves Delivery Specification”
3  Terms and Definitions
Terms and definitions in GB/T 12241 are applicable to this standard.
4  Design, Material and Structure
Design, material and structure of safety valves shall be in accordance with the general
requirements of GB/T 12241.
4.1 General Provisions
4.1.1 Steam safety valves whose set-pressure is larger than 3.0 Mpa; or air or other
gas safety valves whose medium temperature is larger than 235°C shall prevent the
exhausted medium from directly eroding springs.
4.1.2 In design, safety valve shall be guaranteed to reach the rated discharge even it is
damaged partly. When spring is damaged, spare parts such as valve clack shall not fly off
the valve body.
4.1.3 Looseness-proof devices must be installed in order to prevent looseness of
structures for adjusting spring compression amount.
4.1.4 Fall lift and medium lift safety valves shall be equipped with structure controlling
lift height.
4.1.5 Steam safety valve shall be equipped with spanners. When the medium pressure
is over 75% of the set-pressure, spanner can be used to lift valve clacks. Spanners shall
not block valve actions.
4.1.6 Safety valves with poisonous or combustible media shall be closed type safety
valves.
4.1.7 As for safety valves with superimposed back pressure, back pressure balance
mechanism shall be installed with regard to the back pressure size and fluctuation
situation.
h -- Designed lift height (mm).
4.6.13 The spring deformation amount under the maximum working load shall be less
than or equal to 80% of that under the testing load.
4.6.14 The spring deformation amount under the maximum working load shall be less
than or equal to 80% of that when the spring rings fold together.
4.7 Material Requirements
4.7.1 Valve body
The materials of steel valve body shall be in accordance with the provisions of GB/T
12228, GB/T 12229 and GB/T 12230. The materials of iron valve body shall be in
accordance with the provisions of GB/T 9440 and GB/T 12227. The materials of copper
alloy shall be in accordance with the provisions of GB/T 12225. In which, the nominal
pressure of malleable iron valve body shall be controlled to be equal to or less than 1.6
MPa, and that of the spheroidal graphite iron and copper alloy valve body shall be
controlled to be equal to or less than 2.5 MPa.
4.7.2 Valve seat and valve clack
The corrosion resistance performance of valve seat and valve clack materials shall not be
less than that of valve body materials.
4.7.3 Guide sleeve
The guide sleeve materials shall be possessed of favorable wear resistance and corrosion
resistance performance.
4.7.4 Spring
Spring materials shall be adopted according to GB/T 1239.6. And it shall be in accordance
with the requirements of relevant standards.

Basic Data

Standard ID	GB/T 12243-2005 (GB/T12243-2005)
Description (Translated English)	Spring loaded safety valves
Sector / Industry	National Standard (Recommended)
Classification of Chinese Standard	J16
Classification of International Standard	23.060.01
Word Count Estimation	11,182
Date of Issue	2005-02-21
Date of Implementation	2005-08-01
Older Standard (superseded by this standard)	GB/T 12243-1989
Quoted Standard	GB/T 1239.2; GB/T 1239.4; GB/T 1239.6; GB/T 9440; GB/T 12220; GB/T 12224; GB/T 12225; GB/T 12227; GB/T 12228; GB/T 12229; GB/T 12230; GB/T 12241; GB/T 12242; JB/T 7928
Adopted Standard	JIS B8210-1994; MOD
Regulation (derived from)	Announcement of Newly Approved National Standards No. 5, 2005 (No. 79 overall)
Issuing agency(ies)	General Administration of Quality Supervision, Inspection and Quarantine of the People Republic of China, China National Standardization Administration Committee
Summary	This standard specifies: Spring loaded safety valve design, materials and construction, performance, testing and inspection, marking and sealing, delivery and other requirements. This standard applies to: set pressure is 0, MPa ~ 42. 0MPa, flow channel diameters greater than or equal to 8mm- steam boilers, pressure vessels and pipelines valve.