2021-08-19_REVISION - M2012032 (2)

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AFL INDUSTRIES,INC. RIVIERA BEACH,FLORIDA SERVICE INSTALLATION PAGE I OF 4 MANUAL INSTRUCTIONS PRODUCT: HANDLING,STORAGE AND FIELD ASSEMBLY OF PLASTIC PIPING HANDLING AND STORING PLASTIC PIPING Plastic pipe does not require"kid-glove"treatment;however normal precautions should be taken to prevent excessive mechanical abuse. When unloading pipe from a truck,for example,it is unwise to drag a length off the tailgate and allow the free end to crash to the ground. Remember too,that scratches and gouges on the pipe surface can lead to reduced pressure-carrying capacity. Standard-pipe wrenches should not be used for making up threaded connections since they can deform or scar the pipe;use strap wrenches instead. When using a pipe vise or chuck,wrap jaws with emery cloth or soft metal. Pipe should be stored on racks that afford continuous support and prevent sagging or draping of longer lengths. Burrs and sharp edges of metal racks should be avoided. Plastic fittings and flanges should be stored in separate bins or boxes and never mixed with metal piping components. The storage area should be clean and have adequate ventilation. Plastic pipe should not be stored or installed near a steamline or other source of heat that could overheat the pipe. CUTTING PLASTIC PIPE Plastic pipe can be cut easily with a power or hand hacksaw,circular or band saw. For best results, use fine-tooth blades with relatively little set. A circumferential speed of about 6,000 ft./min. is suitable for circular saws; band saw speed should be approximately 3,000 ft./min. Carbide-tipped blades are preferable when quantities of pipe are to be cut. Pipe and tube cutters are not recommended since they might cause excessive heat and pressure that can result in cracked or irregular ends. To ensure square-end cuts,a mitre box,hold-down or jig should be used. All burrs should be removed with a fine-tooth file,deburring tool or sharp knife. Chips,burrs,filings,etc.,should be removed from the pipe I.D.before installation. BENDING PLASTIC PIPE Bending leaves residual stresses in plastic pipe and,consequently,use of bends is not recommended,particularly when the line is to operate at or near maximum-rated pressures and temperatures. Factory-made fittings and straight lengths of pipe invariably give better performance. When field bending is necessary to meet special conditions or to provide for expansion and contraction of the pipe,the following technique should produce good results: l. Seal both ends of the pipe length with plumber's test plugs and introduce sufficient air pressure to maintain ovality of the pipe during bending. The same purpose can be achieved by filling the pipe with pre-heated sand. 2. Heat the pipe uniformly by immersing it in hot oil or water,or by rotating it in front of a hot-air gun. An open flame should not be used. 3. When the pipe becomes soft and pliable,it should be placed in a wooden forming jig or form,and the bend should be made as quickly as possible to prevent weakening or deforming the pipe. The minimum radius to which a bend should be made is 5 to 6 diameters,but the initial forming bend should be slightly greater to allow for springback. 4. The bend should be kept in the forming jig until the pipe cools and becomes rigid;then it should be cooled quickly by immersion in water. Air pressure should not be relieved or sand removed until after final cooling. (Thermoset plastics such as glass-reinforced epoxy cannot be field bent by heating,of course.) SUPERSEDES: 1-0-M: 0.03