METHOD OF MANUFACTURE OF ROLL-TYPE PISTON-SEPARATOR Russian patent published in 2002 - IPC

FIELD: cleaning inner surfaces of pipe lines, separation of petroleum products at successive transfer of these products, forcing air or water out of pipe line during hydraulic tests. SUBSTANCE: piston is provided with hermetic cleaning flexible casing filled with elastic porous material; it is formed by winding flexible strip in roll at force applied at this; strip is made from material which is tight for working medium with backing of definite thickness whose length and width are equal to those of strip. Layer of elastic porous material is saturated with adhesive at equal pitch lengthwise; cover plates are bonded to butts of roll; cover plates are made from the same material as strip; their diameter is equal to diameter of roll. EFFECT: enhanced efficiency and reliability. 3 cl, 3 dwg