(1)
Gas pipeline preparation before construction
①Although the melting point of molten lead refined lead is 327℃, due to the operation in the open air, there is a certain distance between the molten lead and the pouring interface. Considering the temperature drop of molten lead during transportation and pouring, the temperature of molten lead must reach above 400℃ to be used. The simple way to check the lead temperature is to insert a dry iron rod into the lead liquid. If the lead liquid does not stick to the iron rod when it is taken out, and the surface of the blue lead melt is golden yellow, the molten lead temperature has reached over 400°C.
② Check whether there are impurities and oil stains on the mating parts of the socket and socket, and clean them. If a rubber ring is used, the rubber ring selected according to the size of the gap should be placed on the socket.
(2) Fill in the head oil rope or rubber ring
Filling the oil rope Insert the pillow chisel into the gap on the lower side of the interface, hammer the pillow chisel to hold up the socket part, and twist the oil rope to fill the gap. First, fill the bottom oil rope once and make it firm, then from bottom to top, gradually hammer it to fill it, and then make a second circle to fill it with the same method. Strive to be flat all around, and the depth is about 50 to 60 mm from the end face of the socket. The length of the lap at the head and tail of the oil rope is 5 to 7 cm. The oil rope at the two ends of the lap joint should be appropriately thinned, and its position should be placed on the upper side of the interface.
