(3) Take out the milling cutter, close the ends of the two tubes and check the alignment of the two ends. The displacement of the two ends of the pipe should not exceed 10% of the thickness of the pipe or the larger of 1mm. The pipe straightness and the tightness can be corrected to some extent. When the pipe is closed, there is no obvious gap between the two ends of the pipe.
The maximum width cannot exceed: 0.3mm (DN< 225mm), 0.5mm (225mm<DN<400mm) or 1.0mm (DN>400mm). If the above requirements are not met, they should be milled again until the above requirements are met.
(4) Measure the drag force (the frictional resistance of the moving fixture), this pressure should be superimposed on the process parameter pressure to get the actual use pressure. Also check if the heater plate temperature has reached the set value.
(5) After the temperature of the heating plate reaches the set value, put it into the frame and apply the specified pressure until the minimum curl on both sides reaches the specified width, and the pressure is reduced to the specified value (just keep the tube end face and the heating plate in contact) , to absorb heat.
(6) After the time is reached, the movable frame is retracted, the heating plate is quickly taken out, and then the two pipe ends are closed. The switching time should be as short as possible and cannot exceed the specified value. After cooling to the specified time, the pressure is released, the slips are released, and the connected pipes are taken out.
