Cast iron pipes can be divided into gray iron pipes, ductile iron pipes and high silicon iron pipes according to the materials used. Cast iron pipes are mostly used for pipeline projects such as water supply, drainage and gas. In the medium and low pressure pipe network, the cast iron pipe has safe and reliable operation, low breakage rate, convenient and quick construction and maintenance, and excellent anti-corrosion performance. First, the cast iron pipe connection Cast iron pipe cast iron pipe. Cast iron pipes are used for water, drainage and gas transfer lines, which include cast iron straight pipes and fittings. Labor intensity is small. According to different casting methods, it is divided into continuous cast iron pipe and centrifugal cast iron pipe. The centrifugal cast iron pipe is divided into sand type and metal type. According to the material, it is divided into gray cast iron pipe and ductile iron pipe. According to the interface form, it is divided into flexible interface, flange interface, self-anchoring interface, flexible interface and rigid interface. Among them, the flexible cast iron pipe is sealed with rubber ring; the flange interface cast iron pipe is fixed by flange, the inner pad rubber flange gasket is sealed; the rigid joint generally has a large cast iron pipe socket, and the straight pipe is inserted and sealed with cement. This process is now Basic elimination. The connection between the cast iron pipe and the pipe adopts the form of socket type or flange type interface; according to the function, it can be divided into two types: flexible interface and rigid interface. The flexible interface is sealed with a rubber ring, allowing a certain degree of rotation and displacement, so it has good shock resistance and sealing performance. It is simpler and faster to install than a rigid interface. It has different labor intensity according to different casting methods. Second, the characteristics of cast iron pipe 1. The ductility, high strength and pressure resistance of existing steel, as well as the corrosion resistance of gray cast iron; 2. The elongation can reach more than 10%, the tensile strength is more than 420 MPa, and the withstand voltage can reach more than 4 MPa, which is especially in line with the requirements of high pressure and high resistance to deformation of water supply, gas transmission and oil pipeline systems; 3. The stable chemical properties of cast iron pipes are supplemented by anti-corrosion measures such as zinc spray and painting. It has excellent corrosion resistance and has a service life of more than 100 years. 4. Installation and construction is simple and quick, and the project cost is economical; 5, high reliability: cast iron pipe has a high pressure bearing capacity and a certain elongation, and uses a flexible interface, axial displacement of 3 to 5 degrees will not cause media penetration and leakage, with strong earthquake resistance and The ability to prevent underlying subsidence. Third, cast iron pipe installation skills: 1. During the summer construction process, the soil can be properly covered at the interface. 2. The trench backfill should be layered and compacted. If the pipeline crosses the road, in order to avoid crushing the pipe body, the coarse sand can be backfilled to the top of the pipe. 3. If unconditional water pressure test, air pressure test may also be considered. 4. In the hot summer, the oil should be vegetable oil; in the cold winter, the rubber ring can be preheated with hot water to reduce the hardness and install quickly. 5, three-way, elbow must be made of concrete buttress. 6. Interface dripping sometimes occurs during construction. In order to avoid this phenomenon, it is necessary to strictly follow the specifications during installation. It is necessary to ensure that each pipe is installed in place. For large-diameter pipes, check the condition of each interface rubber ring. 7, in order to facilitate installation, you can first wet the rubber ring with water. If the pipe needs to be borrowed during the installation, if the pipe can not be used by the angle of rotation, the pipe socket can be cut and then inclined according to the angle of the borrowing, so that the borrowing angle can be increased. It can also be used safely. Fourth, the selection of cast iron pipe 1 The selection of ductile iron pipe should be based on the specific conditions of the laying site, and the interface form of the straight pipe and the fitting should be selected. 2 It is recommended to use EPDM rubber ring for rubber ring. 3 Coating choice: Select the appropriate coating according to the internal and external conditions at the time of use. The existing inner coating is a new product of ductile iron pipe such as epoxy resin, polyurethane inner and outer coating, PE film coating, etc., and the performance should be understood in detail when selecting. Uvc Panel Lights,Uvc Led Panel Lamp,Uvc Recessed Led Panel Lamp,Uvc Recessed Led Panel Light Top Lighting International (HK) Co., Limited , https://www.topled-group.com