Test method pipe deflection

EN 1226 Glass-reinforced thermosetting plastics (GRP) pipes - test method to prove the resistance to initial ring deflection. 

ISO 13845 2000 Plastics piping systems - Elastomeric sealing-ring type socket joints for use with unplasticised polyvinyl chloride (uPVC) pipes - Test method for leaktightness under internal pressure and with angular deflection. 

ASTM D 3681 [253] Standard Test Method for Chemical Resistance of Fiberglass (Glass-Fiber-Reinforced Thermosetting-Resin) Pipe in a Deflected Condition... 

This test method evaluates the effect of a chemical environment on pipe when in a deflected condition. It has been found that effects of chemical environments can be accelerated by strain induced by deflection. This information is useful and necessary... 

As a vessel is loaded, it moves downward because of deflection of the load cells and support stmcture. Pipes rigidly attached to a vessel restrict its free movement and assume some portion of the load that cannot be measured by the load cells. This is very detrimental to scale accuracy. Deflection of the load cell is unavoidable deflection of the vessel support stmcture should be minimized. Anything which increases vessel deflection, eg, mbber pads used for shock protection, must be avoided. The total number of pipes should be minimized and be of the smallest diameter, thinnest wall possible. Pipe mns to weigh vessels must be horizontal and the first pipe support should be as far as possible from the vessel. Alternatively, a section of mbber hose or flexible bellows should be used to make the final connection to the vessel. The scale should be caUbrated using weights, not by means of an electrical simulation method, which cannot account for the effects of the piping or test the correct functioning of the scale. 

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