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1 0 Repair procedures Dualoy 3000/LCX is very resistant to impact damage. It can be damaged, however, by paving stakes, large concrete pieces or other hazards. In the event of damage, the pipe can be repaired using these procedures. Usually the damaged area is obvious. If the exact location of the damage cannot be determined, it may be necessary to replace that full length of pipe. Standard leak detection methods (soapy water) can be applied progressively along the length of pipe to locate the damaged or defective section. If the primary pipe is leaking at an unknown location, the cut ends of the jacket at each end of each piece of pipe can be soaped to isolate the leak. If the containment pipe is leaking, the surface can be soaped. Minor damage (isolated to less than one inch of pipe length) • Cut out the damaged pipe. Fig. 10-1. Completed repair section using 3- and 4 -inch Dualoy 30001L CX coupling assembly 11 Primary system testing r----------- i These recommendations are offered [ only as a guide. Ameron assumes no responsibility or liability for the consequences of any testing practices. L -----------J r ----------- i [ Ameron recommends hydrostatic ' testing of primary systems as the [ effects of sudden pressure loss when testing with liquids are far less severe [ than with gases. If pneumatic testing is necessary, restrain the system [ [ adequately to prevent damage or [ ' injury in case of rapid pressure loss. ' Pneumatic testing can be extremely [ dangerous and is not recommended. L----------- J 4) • Remove the jacket and taper each of the ends of the remaining pipe • Place the nuts, O -rings and coupling sleeve (2") on the pipe. • Assemble coaxial coupling or primary coupling (molded coupling sleeve placed on pipe) following standard installation practices. • Close containment system and retest. Minor damage [containment only] (isolated to less than one inch of pipe length) • Sand area around damaged area - approximately one inch in all directions. • Recover cut jacket section from field jacket removal tool, remove tape and sand from inner surface. Sand inner surface. • Apply thin coating of adhesive to sanded surfaces. • Wrap jacket section over pipe and secure in place until adhesive cures. Major damage (greater than one inch of pipe length) • Remove at least 15 inches of pipe length or the full length of pipe if damaged area is greater. • Remove the jacket and taper each of the ends of the remaining pipe • Dry fit two couplings and intermediate pipe nipple into the gap. • Place the nuts, O -rings and coupling sleeve (2" and 3") or closure pieces on the pipe and slide back out of the way. • Proceed as above for each end of repair area. Finished repair is as shown below. Once the pipe is buried and the site is paved, repair requirements are extremely rare for Dualoy 3000/LCX. If the pipe does become damaged, sections can be isolated and tested between sumps to locate the problem area. Pavement may need to be removed to access the damaged pipe. Recommended practices Plan tests carefully and carry them out with all due precautions. Pressurizing equipment should be suited to the size of the system and the pressure required and should be operated by qualified and experienced personnel only. • Pressure sources should be capable of approaching test pressure gradually. • Use gauges with a full-scale reading of no more than twice the test pressure: Do not use a 100 psi gauge for a 10 psi test. Use reliable gauges calibrated against a dead weight tester and zeroed for atmospheric pressure. • Isolate tanks from the piping when pressure testing. • The recommended hydrostatic pressure is 150% of expected operating pressure and should be maintained at least 10 minutes. • Do not exceed 150% of system rating. Check the pressure rating of all the components of the system—not just the pipe—because hoses and flexible connectors are almost always rated lower than the pipe. • Do not adjust fittings while system is under pressure. If threaded adapters or bushings leak, release the pressure before attempting to tighten. • Temperature changes can affect the pressure in the test line. Substantial pressure increases may occur in closed systems exposed to the sun.