Method and apparatus for rolling a flat strip of material into a tubular member

1,128,529. Making tubes. STANDARD TELEPHONES & CABLES Ltd. 8 Dec., 1966 [8 Dec., 1965], No. 55108/66. Heading F2P. [Also in Division B8] To wrap a strip of material into tubular form with a minimum overlap of 360 degrees a die is used, said die comprising a first conical portion opening out to a slot in its side, and a second conical portion with no slot. As the strip material is pulled through the first conical portion at least half the width of the strip is allowed to extend out through said slot so that only a portion of the strip width is rolled to tubular formation by the first conical portion. As the strip is pulled through the second conical portion the remainder of the strip is forced to roll around the tubular formation. The strip material may be conductive material and there may be a strip of insulating material between the conductive material and the die. The conductive material may be laminated to the insulating material. An electrical conductor may be drawn through the die at the same time as the strip to cause the strip to wrap around the conductor. The first wrapping around the conductor may be corrugated and the second wrapping may be flat so as to provide an insulated conductor as shown in Fig. 4 (not shown). The outer edge of the strip may be coated on its inner face with adhesive.