Abstract: A machine for cleaning a coupler consisting substantially of a male coupler element and a female coupler element, especially mating surfaces related parts thereof is proposed for avoiding fouling thereof in advance of practical coupling of both the elements. The machine is provided with a ring tube type cleaner unit suspended from a detachable top cover of a cleaning box. The inside space of the ring tube constitutes a liquid chamber supplied with cleaning water from a source and delivers from a number of nozzle openings formed through the inner wall of the ring tube, for delivery of sweep water jets in the center of the ring tube, where the tip and to-be-coupled ends of both the coupler elements are positioned at a small mutual distance. After cleaning jobs, either one of the male and female coupler elements is advanced to mating position for establishing a tight contact with the other one of the coupler elements for avoiding otherwise frequently encountered, disadvantageous fouling.

Abstract: A process for the production of PTFE porous membranes is provided wherein a PTFE preform is prepared by compression molding a PTFE molding powder of 1-90 .mu.m obtained by suspension polymerization of tetrafluoroethylene, the preform is sintered at a temperature above 327.degree. C., followed by skiving the heated preform into a film form. The thus-obtained film is heat treated at a temperature above 327.degree. C., the heat treated film is slowly cooled at a cooling rate of less than 70.degree. C./hr so as to adjust the crystallinity of PTFE in the sintered film to 60-75% and the film is stretched either uniaxially or biaxially to 1.3 to 6.5 times while heating at a temperature of 100.degree.-320.degree. C.

Abstract: A process for producing a polytetrafluoroethylene porous film having excellent mechanical strength wherein pores have a substantially perfect circle and it is possible to uniformly control its pore size to a predetermined size. The porous film is obtained by compression molding polytetrafluoroethylene resin molding powders obtained by a suspension polymerization method to prepare a preform, sintering said preform at a temperature of at least 327.degree. C., forming it into a film, resintering the film at a temperature of at least 327.degree. C., quenching it at a cooling rate of at least 70.degree. C. per hour to reduce the crystallinity of polytetrafluoroethylene to 55% or below, and thereafter stretching said film at a stretch ratio of from 1.3 to 6.5 while heating it to a temperature of from 100.degree. to 320.degree. C.

Abstract: A process for producing a clutch facing which comprises the steps of: impregnating inorganic fibers with a thermosetting resin; causing rubber composition sheets to adhere to the resin-impregnated inorganic fibers, said sheets having been obtained by causing organic fibers to add to a rubber composition as a processing aid and forming the resulting material into sheets; forming a preform therefrom; and molding the preform under heat and pressure.

Abstract: A planar heat generating device is made up of two heat radiating plates having through-holes, heat generating units of positive temperature characteristic material held between the two plates, two lead wires connected to the two plates, and an insulating cover layer of heat resisting synthetic resin which covers the two plates, the heat generating units and the connecting points of the lead wires. Fluid through-holes are formed in the parts of the insulating cover layer which are applied to the through-holes of the plates, so that the heat generated is effectively conducted to the fluid.