Central steel committed to comply with the requirement of the established Quality Management System(QMS) in accordance with the requirement of API Specification Q1 and ISO 9001:2008 Standard and strive for continually improve QMS effectiveness and customer satisfaction through competitiveness and efficiency in manufacturing of steel pipe and steel related services.
To make sure that every pipe leaving our plant conforms to the high standard we guarantee to our customers, our quality control department will follow seven steps to confirm the quality of our product.
1. To detect any area of lamination on the material and dimensional flaws, a manual ultrasonic inspection will be performed on the hot rolled coils before use.
2. To determine the chemical composition and mechanical properties of the skelp, mill tests are run by our quality control inspectors before they are fed to the machine.
3. An ultrasonic examination is run on the formed and welded strip to check for any laminations around the parent metal,defects in the welded seam or heat affected areas.
4. A primary visual and dimensional inspection focusing on the weld bead and the surface condition of the base metal is carried out after cleaning.
5. To further ensure the quality of the weld, a fluoroscopic X-Ray test is carried out to look for possible weak spots. This test is captured on film and can be provided on request.
6. A hydrostatic testing machine will subject the pipe to further analysis identification.
7. Finally, a radiographic X-Ray inspection will take place on both ends of the pipe before a final mill examination.
CHEMICAL AND MECHANICAL TESTING ARE DONE THROUGH GOVT. APPROVED LABORATORIES VIZ.
CHEMICAL TESTING Viz. Carbon, Sulphur, Phosphorus, Manganese, Silicon, Chromium, Nickel, Molybdenum, Copper, Vanadium, Carbon EQ. etc.
MECHNICAL TESTING Viz. Tensile, Yield Strength, Elongation, Fracture, Macro, Flattening and Hardness Dye Penetrant Test, Radiographic Examination on welded Pipes, Ultrasonic Testing etc.
Our on site testing equipment include the following:
Our universal tensile tester is computer controlled, and provides us with real-time complete and concise test results and print outs. These are available for customers to view upon request.
IMPACT TESTERIn order to check the toughness of parent metals and welded specimens, impact tests at room temperature, zero and subzero temperatures can be carried out.
CHEMICAL ANALYSIS TESTING EQUIPMENTChemical Analysis is carried out to check if the steel coil received is in accordance with the specifications and steel mill test certificates before commencing production. This validation analysis will draw immediate attention to any excessive amounts of trace elements, which may affect welding and mechanical properties.
ULTRASONIC TESTINGOur automatic multiprobe ultrasonic flaw detection system monitors the weld integrity and measures the weld bead geometry after internal and external scarfing. Therefore we can ensure consistent quality of the weld seam, giving you peace of mind that the most critical zone in the pipe is made to the highest quality standards possible. The welded seam and the adjacent heat affected zones are tested using 4 to 8 ultrasonic flaw detection probes. Flaws detected are automatically marked by spray guns. Final testing is carried out offline after hydrostatic testing, to ensure that no cracks have developed during the pressure testing process.
HYDROSTATIC PRESSURE TESTING MACHINEThe hydrotester has the capability of pressure testing pipes to a maximum of 28 MPA. The process involves clamping pipes between two test heads and then filling the pipes with water and pressurising to the required specified test pressure. The applied pressure is held for between 5 to 10 seconds, to ensure no leakages, cracks or sweats are detected.