1. Preparation for welding. The preparations for hot melt welding are as follows:
① Put the slips consistent with the pipe specifications into the rack;
② Prepare enough supports to ensure that the pipe to be welded can be at the same height as the center line of the frame and can be moved easily;
③Set the temperature of the heating plate to 200～230℃ (this data is based on the welding machine supplied by Hangzhou Weipin Machinery Factory, and the specific temperature is subject to the data provided by the manufacturer);
④Turn on the power of the welding machine, turn on the switches of the heating plate, milling cutter and oil pump and try running.
Second, welding. The welding process is as follows: Check the pipe and clean the pipe end → Fasten the pipe → Mill the pipe end with a milling cutter → Check the pipe end misalignment and gap → Heat the pipe and observe the minimum crimp height → The pipe is welded and cooled to the specified time → Take out the pipe. During the welding process, the operator should refer to the parameters of the welding process card to operate, and if necessary, should make appropriate adjustments according to changes in weather, ambient temperature, etc.:
① Check whether the specification and pressure level of the pipe to be welded are correct, and check whether the surface is knocked, bumped, or scratched.
②Use a soft paper or cloth dipped in alcohol to remove the oil or foreign matter on the ends of the two pipes;
③Put the pipe to be welded in the rack slips, so that the lengths of the two ends are the same (as short as possible without affecting milling and heating, and should be kept at 20~30mm), and the parts other than the pipe rack are used Hold up the support so that the axis of the pipe is at the same height as the center line of the frame, and then fasten it with slips;
④Insert the milling cutter, first turn on the power switch of the milling cutter, then close both ends of the pipe, and apply appropriate pressure until continuous chips appear at both ends (the thickness of the chips is 0.5-10mm, by adjusting the height of the milling insert Adjustable chip thickness), remove the pressure, wait for a while, then withdraw the movable frame and turn off the power of the milling cutter;
⑤Take out the milling cutter, close the two pipe ends, and check the alignment of the two ends (the dislocation of the two ends of the pipe should not exceed 10% of the wall thickness, which can be improved by adjusting the straightness of the pipe and the tightness of the slips; the gap between the two ends of the pipe should not exceed 10% of the wall thickness. 0.3mm (below de225mm), 0.5mm (de225mm~400mm), 1mm (above de400mm), if they do not meet the requirements, they should be milled here until they meet the requirements.
⑥ After the temperature of the heating plate reaches the set value, put it into the rack and apply the specified pressure until the minimum curling edge on both sides reaches the specified height, and the pressure is reduced to the specified value (the two sides of the pipe end are just in contact with the heating plate, and the After the time is up, loosen the movable frame, take out the heating plate quickly, and then close the two pipe ends to shorten the switching time as much as possible.
