Operation of hot melt butt welding machine

Welding preparation Welding preparation is mainly to check whether the welding machine meets the working requirements. For example, check whether the fasteners of various parts of the machine are loose or loose; check whether the electrical connection of the whole machine is correct and reliable; check whether the hydraulic oil in the hydraulic tank is sufficient; confirm that the power supply matches the input requirements of the machine; whether the heating plate meets the requirements (Whether the coating is damaged); trial operation of milling cutters and oil pump switches, etc. Then install the slips with the same pipe specifications into the rack; set the heating plate temperature to the welding temperature (the welding temperature of the polyethylene pipe channel is 200~230 ℃), before heating, use soft paper or cloth dipped in alcohol to wipe the heating plate Surface, but be careful not to scratch the PTFE anti-sticking layer.

Welding Welding should be carried out in accordance with the parameters of the welding process card. If necessary, it should be properly adjusted according to changes in weather, ambient temperature, etc. The main steps are as follows.
　　
(1) Use a clean cloth to remove dirt from both ends. Place the pipe in the frame slip, so that the length of the two ends protruding is equivalent (in the case of meeting the requirements of milling and heating, it should be as short as possible, usually 25~30mm). If necessary, the parts other than the pipe rack are held up with supports, so that the pipe axis is at the same height as the center line of the rack, and then fastened with slips.

(2) Insert the milling cutter, first turn on the milling cutter power switch, then slowly close the welding ends of the two pipes, and apply appropriate pressure until continuous chips appear on both ends, remove the pressure, wait for a moment, and then exit the activity Frame, turn off the cutter power. The chip thickness should be 0.5~1.0mm, and the chip thickness can be adjusted by adjusting the height of the milling blade.

(3) Take out the milling cutter, close the ends of the two pipes, and check the alignment of both ends. The misalignment of the two ends of the pipe should not exceed 10% of the thickness of the pipe wall or the larger value of 1mm. It can be corrected to a certain extent by adjusting the straightness of the pipe and the elastic slips; there is no obvious gap between the two ends of the pipe when closing 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, milling should be performed again until the above requirements are met.

(4) Measure the dragging force (friction resistance of the moving fixture). This pressure should be superimposed on the process parameter pressure to obtain the actual use pressure. And check whether the temperature of the heating plate reaches the set value.

(5) After the temperature of the heating plate reaches the set value, put it into the rack and apply the specified pressure until the pressure decreases to the specified value when the minimum curling on both sides reaches the specified width (so that the end face of the tube and the heating plate are kept in contact) , For endothermic.

(6) After the time is up, withdraw the movable frame, quickly remove the heating plate, and then close the ends of the two tubes. The switching time should be as short as possible and cannot exceed the specified value. After cooling to the specified time, release the pressure, loosen the slips, and take out the connected pipes.