TESTING PROCEDURE FOR MANUFACTURE OF TUBES FROM ORIENTED PLASTIC MATERIAL Russian patent published in 2000 - IPC

FIELD: manufacture of plastic tubes. SUBSTANCE: in agreement with testing procedure tube is moved and pressure of fluid medium is fed inside. Diameter of tube grows gradually in expansion zone between inlet and outlet end-pieces. Inlet end-piece snugly shuts off tube where it has not been subjected to substantial expansion yet. Outlet end-piece snugly shuts tube after expansion section. Expansion of tube is tested by one or more parameters which express directly or indirectly measurement of difference of rates at which substance is fed into expansion zone and is removed out of it. EFFECT: stable proceeding of process, scope for testing outlet parameters with sufficient degree of accuracy. 8 cl, 3 dwg