Abstract: The present invention suggests a pipe manufacturing method by new plastic bonding with high bonding power and adopted to a thin pipe. With regard to the pipe manufacturing method that bonding fins 3a and 3b are provided at edges 2a and 2b of plural split pipes 2A and 2B split along longer direction and the split pipes 2A and 2B are united by caulking the bonding fins 3a and 3b of the split pipes 2A and 2B, the bonding fin 3a is wound around the other bonding fin 3b for caulking them so as to form creases 35 circularly centering on an axis of the roll form.

Abstract: A fuel reformer suited for mounting on a vehicle is provided. A raw material gas containing methanol and water is vaporized at a vaporization section 30. The vaporized gas flows horizontally to a reforming section 60 with monolithic catalyst 70. The reforming section is divided into two sides, a front side 62 and a rear side 64, with an interconnecting pipe 66 bent at 180 degrees, for connecting the front and rear sides. By making the material gas flow horizontally, even when the reformer is mounted to a vehicle which has a larger space in its horizontal direction than in its vertical direction, especially a small passenger car, the contact time period between gas and catalyst can be extended. By bending the reforming section by 180 degrees, the size of the reformer can be reduced so that the reformer is suited for mounting on a vehicle having limited space.

Abstract: A heat resistant copolymer composition is provided by blending two kinds of copolymers one of which is obtainable by polymerizing a maleimide monomer (A), an aromatic vinyl monomer (B), an unsaturated nitrile monomer (C) and optionally at least one other comonomer copolymerizable therewith (D) in a specific monomer ratio in the presence or absence of an elastomeric polymer and which has an intrinsic viscosity of 0.3 to 1.2 dl/g, and another of which is obtainable by copolymerizing the aromatic vinyl monomer (B), the unsaturated nitrile (C) and optionally at least one other comonomer copolymerizable therewith (D) in a specific monomer ratio in the presence or absence of the elastomeric polymer and which has an intrinsic viscosity of 0.3 to 1.5 dl/g.

Abstract: A short circuiting arc welding machine increases an arc current density by adding a pulsed current having upper and lower limits to a current flowing when an arc is produced, thereby increasing the depth of bead penetration into a workpiece, removing welding defects, and speeding up the welding operation. The welding machine is capable of alternately changing the direction of flow of a welding current at desired periods to produce arcs in straight, reverse and mixed polarities for achieving intermediate characteristics of arcs of straight and reverse polarities, with a resultant ability to adjust in a wide range a wire melting rate and the amount of heat applied to the workpiece.

Abstract: A process for producing by bulk polycondensation an aromatic polyester of the formula, ##STR1## wherein X is a hydrocarbon radical having 1 to 20 carbon atoms, --O--, --SO.sub.2 --, --S--, or --CO--, m is 0 or 1 and n is 0 or 1; when p=0, q=r=an integer of 3 to 600; when q=r=0, p=an integer of 3 to 600; when p.noteq.0, q.noteq.0 and r.noteq.0, p+q+r=3 to 600; p, q, r are integers and q=r, which comprises using a horizontal jacketed reactor provided with one or two agitator shafts bearing impellers fixed thereto and carrying out the bulk polycondensation in said reactor while circulating a heat-transfer medium through the jacket, agitator shaft(s), and, if necessary, impellers to heat or cool the reaction system to obtain a particulate material having a weight-average particle size of 0.5 to 20 mm.

Abstract: A process for preparing polymer resins by polymerization of at least one ethylenic monomer onto at least one rubbery polymer optionally grafted with at least one ethylenic monomer which comprises initiating the polymerization in an emulsion system, adding a suspension stabilizer to the polymerization system at the stage after the conversion of the ethylenic monomer to be polymerized reaches 5% by weight and before the emulsion system is broken and then continuing the polymerization in a suspension system until completion of the polymerization. By the process, polymer resins can be produced in particles having a beautiful appearance and an even particle size with a narrow range of particle size distribution.

Abstract: A process for preparing polymer resins of high impact resistance which comprises coagulating a latex of a rubbery polymer grafted or not with at least one ethylenic monomer in the presence of a suspension stabilizer and a coagulating agent to make a stable aqueous suspension of coagulated particles of said rubbery polymer, adding at least one ethylenic monomer to the aqueous suspension and subjecting the resultant mixture to suspension polymerization.

Abstract: Edges of first and second panel plates to be joined together are butted to each other along a seam to be formed under a backing support by a backing member extending along the seam to lie over both of the two panel plates. The backing member being wide enough to extend over both sides of the seam and having a substantially higher rigidity than the panel plates, wherein the butting edges of the two panel plates and the backing member are all welded together along the seam.