GB1515951A - Methods of cold-bonding metal parts - Google Patents

Abstract

1515951 Frying pans ELPAG AG CHUR 25 Feb 1976 [25 Feb 1975 7 July 1975] 07486/76 Heading A4A [Also in Divisions B3 and F4] In a method of cold bonding a pair of metal parts, one of the parts or an insert 1 has holes 2, 3, 35 punched in it so that the edges of the holes protrude from the plane of the insert, the parts are pressed together or on to the insert so that the protruding rims penetrate into the surface of one or the surfaces of both parts, the metal of the part or parts flowing into the holes. The insert 1 is made from stainless steel and the holes 2, 3 are punched from opposite sides. The insert is placed between two metal sheets (4), (5), Fig. 3 (not shown), which may be of different metals, or the insert may be used to secure a tubular heating element (11) to an aluminium plate (12), Fig. 7 (not shown). To make a frying pan, holes are formed in a stainless steel base 6, Fig. 5, which is pressed into a plate 9 of aluminium or copper, the material of the plate forming rivet head shaped protrusions in the holes. A water heater is made from an Al-Mg-Si alloy pipe 31, Fig. 18, having an integral longitudinal rib 32 formed with holes 35. A magnesium oxide filled tubular heating member 37 is bent to the shape of the pipe 31 and protruding rims 36 of the holes 35 into the aluminium casing of the member 37 as far as the filling. This allows for the escape of moisture in the filling during annealing and to prevent reabsorption of moisture silicone oil is mixed with the magnesium oxide. A thermostat is mounted on a bridge 38 fitted near the pipe ends and the pipe is indented, e.g. at 41, 42, to form steam spaces to allow for uniform water flow. A bi-metallic coil 43 inside the pipe expands and contracts with water temperature variation to prevent lime deposits forming on the tube walls.