TESTING
a) Tensile Test
Tensile test is done on samples drawn from fittings or starting material in accordance with specificafications as required by the purchaser at a subcontracted metallurgical laboratory.
b) Hardness Test
Hardness testing is carried out as per requirement of purchase order and / or the specification. The results obtained are recorded & used for certification.
c) Impact Test
Impact test is done on those materials conforming to ASTM 420/A350 as required by the code. 3 samples from each batch of material are tested for their impact properties at the temperature specified by the code, grade of materials and carried out at an extenal Laboratory.
d) Ultrasonic Testing
This is done incase of supplementary requirement of the purchaser, on raw materials or finished products, as called for.
e) Microstructure Examination
As per ASTM A 262 and its practices as called for by client or parent code of manufacture.
f) Die Penetrant Test / Magnetic Particle Examination
All reducers with half or more reductions, caps, Tees are die penetrant tested within the works. Apart from die penetrant tests at regular manufacturing intervals, all the welds made by the operator on the pipe fittings are 100% X-Ray examined as required by the code and viewed on viewer. CS and AS tees are subjected to MPI and test result recorded. Other fittings also are supplied with MPI if required by ctient as supplementary test.
DIMENSIONAL CONTROL
Machining is carried out as per the required dimensional specifications. Adequate templates, fixtures are maintained to guide the dimensions required. Calibrated measuring instruments are used for checking various dimensions. Fittings are then deburred. Threads of Screwed fittings. checked with the help of thread gauge/plug gauge. All templates fixtures & gauges are regularly checked to ascertain that they are dimensionally stable.
FINISHING
Shot/Sand Blasting is done on carbon steel and alloy steed fittings whereas stainless steel fittings are pickled & passivated to remove the scale and stabilize the surface. A proper concentration of solution is maintained. CS/AS Fittings are then painted for protection against corrosion.
MARKING
The fittings, inspected for various dimensions are then stamped for the required specification alongwith company’s stamp.
CERTIFICATION
The fittings are supplied alongwith the manufacturer’s certificate which incorporates the following details, where ever whatever applicable : a) Chemical Analysis Results b) Tensile Test Results c) Hardness Values d) Type of heat treatement e) Nomenclature f) Results of any suppliementary tests. like impact, IGC, MICRO, ultrasonic and MPI
CONCLUSION
The “quality assurance programme” as documented here is an abridged version. This programme is pursuent to achieve desired quality levels. Detailed documents and operational data maintained by manufacturer can be reviewed by customer’s engineers on request. The programme is periodically upgraded, deleted and revised due to change in technology, process improvement or revision in applicable codes.