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- Pipe spools are fabricated to proprietory drawings covering standard spool, minimum spool lengths by Nominal Bore size and Jactetted pipes.
- Approved weld procedures for flange attachment and setting are adopted and welded carried out by qualified welders.
- When fabricating pipes and fittings, end connections shall be manufactured to provide a minimum 1/8th inch radius or chamfer in the transition from pipewall to flange or lap face. This radius or chamfer is required to reduce stress concentration in the plastic liner as it is flared or moulded over the flange face or stub end.
- All pipe spools have lap joints flange (flange rotates on pipe) at one end and fixed flange at the other end.
- The interior surface of all the Housings shall be clean and free of burrs, rust, scale or other protrusions which may adversely affect the integrity or performance of the lining.
- As a standard Lined pipes are manufactured upto a max length of 3 metres in all sizes and for all lined material. Longer lengths can be made available for which the factory has to be consulted.
- All fittings are with fixed flanges either cast on or welded.
- All Pipes and Fittings must be vented in compliance with ASTM F 1545. Vent Systems are designed to release any gases between the liner and the housing - preventing build up of those gases which could cause premature failure of the lined system.
- Precaution should be taken to see that these Vent holes are left open at all times and care should be taken when painting the pipe work during installation and maintenance Each pipe assembly and fabricated fittings are provided with vent holes drilled into the metal housing prior to lining. Two pairs of vent holes for each pipe spool 180 degree apart and located 150 mm from each flange face are provided. Each pair of these vent holes are drilled rotated 90 deg to each other. For pipe assemblies 500 mm or less only one pair of vent holes located between the flanges are required. Cast fittings are vented at the injection boss. In addition these vent holes serve as weep holes in the evnt the liner is damaged. Vent holes extensions are necessary in the event pipes and fittings are required to be insulated or if the emission of vented materials are to be kept away from the flange bolts.
- All linings shall fit snugly into the pipe and fitting housings. Any bulges in lining or indication of poor contact with the housing shall be a cause for rejection.
- Plastic pipe liner shall be locked into the pipe housing using the thermolok process to provide dimensional stability which would be necessary as the pipe would have to with stand the thermal cyclic conditions and also to provide maximum vacuum resistance at elevated temperatures.
- The gasket seating surface of the lining shall be free of the surface defects that would impair sealing effectiveness. Scratches, dents, nicks or tool marks on the seating surface shall not be deeper than 10% of the face thickness.
- Minimum liner thickness on the flare face shall be 80% of minimum liner wall thickness.
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