- The Quality Assurance Plan for manufacture and acceptance test is generally in conformity with various national and international standards like BIS, ISO & API etc.
- Raw materials are tested for quality at vendors' works. Day batches are tested for a few key parameters like moisture, viscosity etc.
- The processing is done in a batch sufficient for the day's moldings. Out of the days green pieces, one piece is tested destructively and the remaining pieces are sent for heat treatment after 100% check on dimensions, density and surface defects.
- The heating cycle is closely monitored to impart the desired curing, grain structure morphology and mechanical strength. 100% of the heat-cured pieces are subjected to apparent porosity test. CCS is checked on two pieces of tiles and bricks out of the day's production. One larger block is type tested every week for the assessment of CCS, inside microstructure homogeneity and thermal treatment efficacy. The articles are then sent to machine shop.
- Machine shop shapes the tiles and bricks to the desired sizes and tolerances. The lining stock is sent for stores. The heat and mass transfer related blocks are sent for impregnation.
- 100% of the impregnated stock is subjected to vacuum test at 0.05bar and hydrotest at 8bar. Distinct record is maintained for each block with traceability.
- The assembly shop for heat and mass transfer equipment checks for alignment of the graphite stack and then tunes the gasket compression to withstand 0.1bar on process side and repeats the test with hydro at 7bar before going for shelling the stack. The shelled stack gasket tuning is tested at room temperature with simultaneous application of air vacuum of 0.1bar on process side and 7bar hydrostatic pressure on service side. Tested okay assemblies are released for final painting.
- The lining shop checks imperfections in cemented joints visually, on reactors, nozzles, flanged faces and agitators. Line pipe assembly pieces are hydrotested at 3bar before cementing.
- The rector fabrication and assembly shop gets test certificated carbon steel. The rolled shells and dished ends are checked for dimensions and ovality. Welding set up is checked for root gap and surface matching. Weldments are subjected to DPT.
- Radiography is done on client instructions.
- Completed assemblies and flanged sub assemblies are hydro tested at 10bar. Lined agitator is subjected to rotation test in air to measure wobble and then released for assembling to the lined vessel. After assembly to the vessel the agitator wobble is measured for in-water rotation. The units are then released for painting and packaging.
- Rupture Disc manufacture is subjected to the API code as detailed below.
- Raw materials of accepted quality are processed in a batch sufficient to make 10 green pieces.
- Out of 10 green pieces, one piece is tested destructively and the remaining 9 pieces are sent for firing.
- The nine pieces are subjected to non-destructive testing of 3 parameters and if any 2 pieces are rejected then one of the remaining 7 pieces is subjected to destructive testing. Usually remaining 6 pieces are sent for impervious treatment and then one piece is destructively tested to confirm the rupture pressure.
- The acceptable 5 pieces are then released for buffing, polishing and gasket face making. One randomly selected piece is subjected to rupture test in the presence of Customer. If 1st piece gives satisfactory results, the 2nd test piece is not subjected to rupture test. Remaining 4 or 3 pieces are then packed along with their gaskets and housing flanges with identification marks.