GB825784A - Improvements in or relating to the production of tubular pipe coverings - Google Patents

Abstract

825,784. Corrugating paper &c. NICOLET INDUSTRIES Inc. April 29, 1957, No. 13639/57. Class 141 [Also in Group XXVIII] In a process for the continuous manufacture of corrugated tubing, a dry strip 10c cf asbestos paper passes between main and auxiliary corrugating rolls 30, 31 and between a roll 30 and a backing roll 32, and a backing-tape 10d moistened on the underside thereof with an adhesive passes over rolls 33, 34 to enter between the rolls 30, 32 together with the dry, corrugated tape 10e, the composite strip 10f being then delivered over a roll 35 driven by a belt 36 to a winding head. The bearing blocks 32a of the roll 32 are urged by springs toward fixed bearing blocks 30b of the roll 30, the minimum clearance between these rolls being adjusted by a wedge block 38 and screw 38a; the bearing blocks 31a of the roll 31 may be similarly mounted. The shaft 30a is driven via a V-belt drive by a variable speed hydraulic motor. The composite strip 10f from the roll 35 passes downwardly and upwardly about a tension controlling means comprising a roller carried by a lever counterbalanced by a spring; as the roller is raised by the winding head drawing the strip 10f from the loop more rapidly than the strip is supplied thereto by the corrugator, the lever operates a speed control valve to increase the rate of driving of the shaft 30a by the motor, and vice versa.