摘要:
A highly stretched film has permanently heat-sealed edges that are nearly invisible. A folding apparatus folds the edge portions of a film to form folded edges. The folded film then is passed through a bridle mechanism having two heated rolls. A series of nips apply pressure to the folded film as it is heated by the heated rolls. The nip pressure, combined with the heat imparted by the heated rolls, causes thermal welding of the folded edges resulting in permanent heat-sealed edges. Because the film edges are folded prior to the hot-stretching, the hot stretch process performs dual functions of stretching the film and heat sealing the folded edges. The resulting stretched film has permanently heat-sealed edges that do no separate, and which prevent tearing of the film edges during subsequent processing and use.
摘要:
An apparatus and high speed process for heating and stretching a film having a bridle mechanism comprising a first heated roll and a second heated roll. The film is stretched as the film is transferred from the first heated roll to the second heated roll which rotates at a speed greater than the speed at which the first heated roll rotates. The film is fed into the bridle mechanism at a rate of about 1,500 fpm to about 2,500 fpm wherein it is stretched to a length that is up to about 450% greater than its initial, pre-stretched length. The increased contact between the large diameter heated rolls and the film and the short draw gap between the two heated rolls result in a highly stretched film having minimal neck-in.
摘要:
A seamless tube useful in making a roofing batten is extruded from a polymeric material consisting essentially of a major amount of poly(ethylene terephthalate) and a minor amount of at least one polyolefin, flattened in a vacuum sizer so as to define two plies, and milled and drawn so as to orient the tube longitudinally. As milled and drawn, the tube is oriented so as to have a tensile strength of at least about 25,000 psi in a longitudinal direction. The plies are punched so as to have holes therethrough at spaced intervals along the tube. When used to make a roofing batten to coact with conventional fasteners, such as roofing screws, the tube exhibits superior characteristics of split resistance and pull-through resistance.
摘要:
A method and apparatus for wrapping and securing film about a load by positioning a first arm retaining an end portion of film toward the load, wrapping a layer of film about the first arm so the first arm is between the wrapped film and the load, withdrawing the first arm retaining the film from between the wrapped film and the load, and releasing the end portion of film retained by the first arm to position and secure a first film portion between the wrapped film and the load. The load is further wrapped and a second arm is subsequently positioned toward the load, and a layer of film is wrapped about the second arm so the second arm is between the wrapped film and the load. A roped film portion is captured and retained by the first and second second arms. The roped film is then severed and an end portion of the severed film is retained by the first arm for subsequently wrapping another load. The other end of the severed roped film portion is retained by the second arm, which is withdrawn from between the wrapped film and the load to position and secure a second film portion between the wrapped film and the load. The arms are withdrawn along a relatively straight path by laterally translating the arms while pivoting thereby reducing contact between at least the portion of the arm retaining the film tail and the wrapped film.
摘要:
A seamless tube useful in making a roofing batten is extruded from a polymeric material consisting essentially of a major amount of poly(ethylene terephthalate) and a minor amount of at least one polyolefin, flattened in a vacuum sizer so as to define two plies, and milled and drawn so as to orient the tube longitudinally. As milled and drawn, the tube is oriented so as to have a tensile strength of at least about 25,000 psi in a longitudinal direction. The plies are punched so as to have holes therethrough at spaced intervals along the tube. When used to make a roofing batten to coact with conventional fasteners, such as roofing screws, the tube exhibits superior characteristics of split resistance and pull-through resistance.
摘要:
A seamless tube useful in making a roofing batten is extruded from a polymeric material consisting essentially of a major amount of poly(ethylene terephthalate) and a minor amount of at least one polyolefin, flattened in a vacuum sizer so as to define two plies, and milled and drawn so as to orient the tube longitudinally. As milled and drawn, the tube is oriented so as to have a tensile strength of at least about 25,000 psi in a longitudinal direction. The plies are punched so as to have holes therethrough at spaced intervals along the tube. When used to make a roofing batten to coact with conventional fasteners, such as roofing screws, the tube exhibits superior characteristics of split resistance and pull-through resistance.
摘要:
A seamless tube useful in making a roofing batten is extruded from a polymeric material consisting essentially of a major amount of poly(ethylene terephthalate) and a minor amount of at least one polyolefin, flattened in a vacuum sizer so as to define two plies, and milled and drawn so as to orient the tube longitudinally. As milled and drawn, the tube is oriented so as to have a tensile strength of at least about 25,000 psi in a longitudinal direction. The plies are punched so as to have holes therethrough at spaced intervals along the tube. When used to make a roofing batten to coact with conventional fasteners, such as roofing screws, the tube exhibits superior characteristics of split resistance and pull-through resistance.
摘要:
A canister for a coating applicator system has a flexible barrier separating a coating-containing region in the canister from a region containing a force applicator for moving the barrier to dispense the coating. While the volumes of each region change upon movement of the barrier, surfaces defining the regions remain in that region.
摘要:
A shuttle push system (10) is provided with a displacing object (36) for insertion into a supply tube (26) and removal from the supply at spaced locations. A return tube moves (34) the displacing object between the position at which it is removed (32) from the supply tube and the position (30) at which it is inserted into the supply tube.
摘要:
A spray applicator system is provided with a reservoir manifold assembly having a separate reservoir for each different coating to be applied. Reservoirs are filled from a coating supply system and isolated electrically from the supply system when coating is dispensed from a reservoir to the applicator. Multiple sets of reservoirs can be used, so that an empty reservoir in one set can be filled while coating is dispensed from a reservoir in the other set. The set of reservoirs in which a reservoir is being filled is isolated electrically from the applicator, and of the set of reservoirs in which a reservoir is dispensing coating to the applicator is isolated electrically from the supply system.