Abstract: The method resides in profiling a part of a cylindrical pipe by drawing it through a moulding device, and reducing the pipe over its entire length for the diameter of the cylindrical part of the pipe to be substantially equal to the diameter of the circumscribed circle of its profiled part.The apparatus for performing the method comprises a drawing bench supporting a drawing die (2) accommodated in a housing (1) and a drawing carriage. Cams (6) are situated in front of the drawing die (2) at both sides of the path of the travel of a pipe (5) being manufactured, their one ends carrying deforming rollers (7) and their other ends carrying forked levers (8) cooperating with the drawing carriage through a tie (11) with slots (10) receiving therein lock pins (9) adapted to engage the forked levers (8). The apparatus further includes a pivoted lever (29) with a bearing roller (31), mounted on the housing (1).

Abstract: A thermal-mining method of oil production is effected by digging a combination of underground workings and at least one working tunnel and by drilling injection and producing wells from said working tunnel. Then a heat carrier is forced into the oil-bearing bed for heating it to a temperature sufficient for the oil to acquire the necessary fluidity. The heat carrier is forced into the oil-bearing bed through injection wells at time intervals t.sub.1 found from an appropriate relation. The oil is withdrawn from the oil-bearing bed through the producing wells at time intervals t.sub.3 in which the time interval t.sub.1 of heat carrier injection into the injection wells is divisible by the time interval t.sub.3 of oil withdrawal from the producing wells, the multiplicity factor being equal to n=(t.sub.1 /t.sub.3).gtoreq.60.