Abstract: A rotary ball valve comprises a housing formed of plastic material, the housing including a through passage. A plug formed of a plastic material is rotatably mounted in the housing and includes a ball-shaped gate having a passage which is alignable with the housing passage when the plug is open. A stem projects laterally of the housing passage to enable the plug to be manually rotated. A pair of seating rings formed of an anti-friction material encircle respective ends of the gate passage when the plug is open. The housing includes a pair of annular flanges disposed on opposite sides of the plug passage. Each flange contacts a back side of a respective one of the seating rings. Each flange is notched around its periphery to form a plurality of circumferentially spaced flange segments whose inner diameter is substantially the same as the diameter of the gate passage.

Abstract: An apparatus for the precision positioning of electrostatic pinning means. The electrostatic pinning means, which significantly improves pinning of a thermoplastic polymeric film cast upon a moving surface, by electrostatic force, is precisely positioned, in relation to an extrusion means and the moving surface, by means of the precision positioning apparatus. The apparatus includes a frame moveable in vertical and horizontal directions. The apparatus further includes the pinning means and support means, connected to the frame, for holding the electrostatic pinning means. Horizontal and vertical adjusting means comprising horizontal and vertical actuating means connected to horizontally and vertically moveable means responsive to the horizontal and vertical actuating means, respectively, are connected to the frame to permit separate horizontal and vertical movements to precisely position the electrostatic pinning means.

Abstract: An adjusting means for controlling the thickness of extrudate exiting from a die. The adjusting means includes a non-flexible block, connected to the die and provided with a tapped hole. Another block, a flexible block is also provided. It is connected to a flexible lip of the die and is also provided with a tapped hole. A bolt which includes a first threaded cylindrical section having a first threaded pitch is also provided. The first threaded cylindrical section is accommodated in the tapped hole provided on the non-flexible block. The bolt further comprises a second threaded cylindrical section having a second thread pitch accommodated in the tapped hole provided on the flexible block. The first and second cylindrical sections are distinguished in that the first and second thread pitches are different.