Bolted repair

Bolted repairs require similar skills and processes to repair of metal structure meaning materials, equipment and skills are more readily available, so there is an... 

Analysis of a bolted repair follows the analysis of a bolted joint. The behaviour of composites in bolted joints differs considerably from what occurs with metals. The brittle nature of composites necessitates more detailed analysis to quantify the level of various stress peaks as stress concentrations. Composite joint design is more sensitive to edge distances and hole spacing than metal joint designs and requires specialised fasteners. Interference fit fasteners or rivets must not be used but expanding sleeves can be installed as required. 

Make sure all gaskets are in good repair and bolts are properly tightened. 

A cover plate on a pump housing is held in place by eight bolts. A pipe fitter is instructed to repair the pump. The fitter removes all eight bolts only to find the cover plate stuck on the housing. A screwdriver is used to pry off the cover. The cover flies off suddenly, and toxic liquid sprays throughout the work area. Clearly the pump unit should have been isolated, drained, and cleaned before repair. There is, however, a better procedure for removing the cover plate. What is this procedure ... 

Ristau C, Bolt HM, Vangala RR Formation and repair of DNA lesions in kidneys of male mice after acute exposure to methyl chloride. Arch Toxicol 6Y254-256, 1990... 

Total restoration costs approached 35,000. Foundation repairs including resetting the anchor bolts and other support work cost about 5,000. An additional 30,000 was spent to lift the tank, fabricate and install a new tank bottom, and to reinstall and reconnect the pipe the vessel. 

After the repairs, the painters started the portable air compressor. The pressure in the sand pot increased. Without warning, employees in the area heard a loud bang. Three of the four stud bolts (which were hardened and made brittle by the heat of the welding operation) snapped apart. The sand pot charging lid harmlessly flew open. 

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