Before the installation should be cleaned up, to clean up the parts include: Socket end, socket inside, the corners of the socket to the white line should be smooth, no sharp points, lest the installation of scratches on the apron. Use edible oil as lubricant and evenly brush on the socket end and rubber ring. The socket is inserted into the socket so that the central axis of the pipe or pipe fitting to be connected is coincident, and a guide chain is slowly tightened in the Tube section until the Cheng enters the middle of the two white lines. The pipe interface allows deflection of 3 °, if the deflection angle of the pipeline is larger, can be used more than just the child deflection, should avoid the single pipe interface deflection angle is too large, general 10 within the angle can use $number root pipe deflection, do not need to use the elbow. Some pipes because of the brutal loading and unloading, resulting in cracks or deformation of the socket, it is necessary to cut off this part, at the same time because the installation of bends, valves, and so on, need different lengths of pipe, also need to cut pipe. Cutting tools can be used for grinding wheel cutters. The cutting line should be marked along the tube for a week, so that it is easy to cut straight. The new cutting pipe socket ends must be trimmed and polished to make the same appearance size as the original Jack end. The anticorrosion of the nodular graphite tube has a direct bearing on the long-term use and safety of the pipeline, so it is an important index to measure the network technology and operation condition. Graphite in Nodular cast iron exists in spherical form because of graphite, which does not affect mechanical and mechanical properties of matrix materials. However, according to the results of 10 typical cities, the static leakage rate of urban water supply pipe network in our country reaches 12 ~ 13%, which is far more than the standard of the country to control the urban leakage rate under 6%, so pipeline anticorrosion has always been a hot topic for us at present. The proportion of ferrite and pearlite in the matrix is different, the proportion of pearlite in small-caliber is not more than 20%, and the general control of large caliber is about 25%. Ductile iron pipe is better than cast steel, so it is more advantageous to reduce stress. One of the important reasons for selecting the ball-ink tube is that the ball-ink tube is lower than the cost of cast steel. The low cost of ductile iron makes this material more popular, the casting efficiency is higher, and the machining cost of the ball-ink tube is less. The ball-ink tube is magnesium or rare earth magnesium combined with gold pellets before pouring into molten iron, so that graphite ball, stress concentration reduced, so that the pipe has a large strength, high elongation, impact resistance, corrosion resistance, good sealing and so on; the inner wall is lined with cement mortar, it improves the pipeline water conveyance environment, enhances the water supply capacity, reduces the energy consumption, the pipe mouth uses the flexible interface, and the tube itself has the large elongation rate ($number), makes the pipeline flexibility is good, in the buried pipeline can work with the soil body around the pipeline, The stress state of the pipeline is improved, which improves the reliability of the pipe network operation.