According to written procedures the whole manufacturing process of ball valves is continuously monitored by the following inspections and tests performed during:
Customer evaluation and monitoring
Checking of raw incoming materials certification
Inspection of manufacture of valve components
Pressure tests
Functional tests
Non-destructive tests
Final inspection of finished valves
Standard Test
Pressure tests
Every ball valve shall be pressure tested in accordance with API 6D requirements, including double block & bleed and double piston effect tests, where applicable.
Specified by the purchaser, the following different tests can be performed to verify valve properties and performances, to verify material chemical composition or mechanical properties, to qualify valves to special working conditions or to long working life.
Valve Tests
Pressure test at high and low temperatures
Low and high pressure seat gas test in accordance with Annex C of API 6D
On customer request pressure tests can be performed in accordance with other standards like API 598 and EN 12266-1
Anti-static test
Torque test, torque value is verified during this test as well
Functional valve test or functional valve and actuator test
Fugitive emission test to ISO 15848 or to other standards
Paint dry film thickness check
Insulating coat testing by holiday detector ISOL test HD93
Cavity relief test
Cryogenic test down to minus 196 °C
Strain gauge test
Hyperbaric test
API PR2 test
Non-Destructive Material Tests
All tests performed by qualified personnel, certified in accordance with ISO 9712 or SNT-TC-1A
Radiographic examination (RT), X-Ray or Gamma-ray
Magnetic particle examination (MT)
Ultrasonic examination (UT)
Dye penetrant examination (DP)
Positive material identification (PMI)
Hardness test
Destructive Material Tests
Mechanical tests, hardness test and Impact test down to – 196°C
Chemical analysis of carbon, stainless steels, duplex, super-duplex and high alloys using spectrometer
Corrosion tests (e.g. Pitting, SSCC, Huey, Crevice)
Micro examinations by electronic microscope up to 500x magnifications
Ferrite check to E562
Hydrogen-inducted cracking test (HIC)
Pull-off test for paint adhesion check
Qualification Tests
Fire tests
Fugitive emission tests
High pressure gas tests
High and low temperature tests
Delayed torque tests
Cycle operational and pressure test
Abrasion tests
Slurry erosion tests
Micro hardness tests
Adhesion tests
Corrosion tests
Porosity analysis
Impact testing
Residual stress analysis
