Reasons for the installation of the ball well cover not in place:

Sphere duct cover is widely used in urban water supply pipeline network because of its high strength, great toughness, good closure performance, strong corrosion resistance and convenient installation and construction. This paper analyzes and discusses some common problems in the installation process of the commonly used sphere duct cover, for reference: the commonly used installation method of sphere duct cover with DN600 and above. However, it is not easy to install the pipeline in place when the pipeline is installed according to this method.
         When installing, the pipe is not evenly stressed or the pipe is not properly hoisted, resulting in increased friction resistance, thus the pipe is not easy to be in place. Because when the rope pulley is used for installation, it is not easy for the pulley on both sides of the pipe to be on the center line of the pipe, and even if the force on both sides of the pipe is the same, it can not guarantee that the pipe is stressed evenly. In view of this situation, we made a steel saddle (its inner diameter is slightly larger than the pipe's outer diameter), and welded a hook under its lower mouth, which is located on the center line of the pipe. When installing, place the saddle at the bell end, and then install it as shown in Figure 2. In this way, it ensures that the pipe on both sides of the installation is stressed evenly.
         When the rubber seal ring of the sphere duct cover is not installed correctly, the rubber ring is prone to deviation from the original position due to the large friction force when the pipe is installed. Because of the unstandardized operation in the process of transportation and hoisting, the socket is not round, resulting in difficulty in installation. This situation is relatively rare. For the socket that is not round, it is necessary to use a special tool to round it. Because the commonly used lubricant is soap water, it hardly plays a lubricating role in the water ditch groove or at a higher temperature, in this case, we usually choose a food oil with a higher viscosity as a lubricant.