All Advance Valves are inspected and tested at the factory as per procedures, that are in strict compliance with API and BS Specifications.
Inspections and Testing of Advance Cast Steel Valves are done as below.
1. Visual Examination
2. Hydrostatic shell test.
3. Backseat test.
4. High pressure test.
5. Low pressure test.
Advance Cast Steel Valves are inspected and tested in detail as follows.
1. VISUAL EXAMINATION :
(Gate, Globe, Ball, Butterfly and Swing Check Valves)
A visual examination is performed on all Casting of bodies, bonnets, covers and closure elements in accordance with MSS-SP-55, Quality Standards for Steel. Castings and with reference to purchase specifications.
2. HYDROSTATIC SHELL TEST :
(Gate, Globe, Ball, Butterfly and Swing Check Valve)
The purpose of this test is to ensure that the valve shell will withstand pressures up to 1.5 times of the working pressure at the 100 o C for Body & 1.1 times for seat rating with no visual leakage or harmful in elastic deformation.
a) Frequency of Hydrostatic Shell Test.
100% on all bodies.
b) Test Media
The test media is water containing a rust inhibitor at a temperature not exceeding 100 o F.
c) Test Pressure
The shell test pressure is 1.5 time of the working pressure rating of the valve at 100 o C, as per the standards.
d) Test Pressure
The shell test pressure is 1.5 time of the working pressure rating of the valve at 100 o F, as per the standards.
TEST PRESSURE (PSIG)
Class 600 (WCB)
Class 600 (Other than WCB)
e) Test Duration
MIN. TEST DURATION (SEC)
14" & OVER
f) Test Procedures
The shell test is performed by partially opening the valve assuring that all internal surfaces seals and packing are exposed to the test media and to apply pressure for the suitable time duration.
g ) Acceptance/Rejection-criteria
No. visible evidence of external leakage for the duration of the test.
3. BACKSEAT TEST
(Gate and Globe Valves only)
The purpose of the backseat test is to ensure that the stem backseat area will not leak at 1.1 times the pressure rating at 100 o C.
a) Frequency of Backseat Test
100% on all Gate and Globe Valves.
b) Test Media
The test media is water containing a rust inhibitor at a temperature not exceeding 100 o C.