Abstract: This invention relates to a water-soluble lubricant for warm or hot metal forming, comprising a high polymer compound which comprises an imide group, which has a weight-average molecular weight of from 1,000 to 1,000,000. The water-soluble lubricants of the invention possess exceptional lubricity for reducing friction between a die and a workpiece, have a minimal adverse effect on the operating environment, and can readily be treated in wastewater.

Abstract: This invention provides a water-soluble lubricant for warm or hot metal forming that possesses exceptional lubricity intended to reduce the friction between a die and a workpiece, has excellent operating environment properties, and can be readily treated as wastewater. In the water-soluble lubricant of this invention for warm or hot metal forming, sodium salts of an imidated isobutylene/maleic anhydride copolymer, which is obtained by imidating part of a copolymer of maleic anhydride and isobutadiene and which has an imidation ratio of 1 to 80 molar percent and a weight-average molecular weight of 1,000 to 1,000,000, is contained in an amount of 1 to 70 mass percent per 100 mass percent of the water-soluble lubricant for warm or hot metal forming.

Abstract: A welding fuel tank has a magnet 3 disposed on the inside or outside thereof in the vicinity of a fuel pump 12 which is housed inside the fuel tank. The magnet collects magnetic spatter which remains inside the fuel tank after welding and prevents the spatter from entering the fuel pump. The magnet may be a permanent magnet or an electromagnet, and it may be disposed outside the pump or in the fuel filter of the fuel pump. A cleaning method for a welded fuel tank comprises introducing a magnet into a fuel tank after welding, vibrating the fuel tank so that the magnet will move about the inside of the fuel tank and collect magnetic spatter, and then removing the magnet and spatter from the fuel tank.

Abstract: A 3 fuel tank has a magnet 3 disposed on the inside or outside thereof in the vicinity of a fuel pump 12 which is housed inside the fuel tank. The magnet collects magnetic spatter which remains inside the fuel tank after welding and prevents the spatter from entering the fuel pump. The magnet may be a permanent magnet or an electromagnet, and it may be disposed outside the pump or in the fuel filter of the fuel pump. A cleaning method for a welded fuel tank comprises introducing a magnet into a fuel tank after welding, vibrating the fuel tank so that the magnet will move about the inside of the fuel tank and collect magnetic spatter, and then removing the magnet and spatter from the fuel tank.

Abstract: A rotary positive displacement pump of the pin roller type comprising a pump housing made of aluminum having a pump chamber with the inner periphery being cylindrical, which is fixed between a pump base and a pump case, a rotor eccentrically located within the pump chamber and driven by a motor, a plurality of rollers made of synthetic resin which is inserted in clearance grooves formed on the outer periphery of the rotor, wherein a centrifugal force generated when the rotor rotates moves the rollers toward the inner wall of the pump housing thereby to form a pump operation space.