What are the pipe connection methods when using pipeline pumps?

What are the pipe connection methods when using pipeline pumps?

         The PTFE lined pipeline pump is a chemical centrifugal pump with an outer cast steel lined PTFE vertical structure. It is suitable for transporting acid, alkali, salt and other highly corrosive liquids. The PTFE lined pipeline pump is also called a pipeline booster pump and stands in the middle of the pipeline. , so what are the pipe connection methods during installation and use?

         1. Flange connection

         A.Pipe flange

        1. The matching flanges have the same specifications and models; when connecting to the equipment flange, they should be matched according to their specifications;

        2. The flange connection is coaxial and parallel, and the flange surface is perpendicular to the center of the pipe; the two screw holes on the horizontal pipe flange are kept horizontal, and the two screw holes of the vertical pipe flange against the wall are parallel to the wall.

        3. The fastening bolts must be of the same specification and direction, and the exposed length of the bolt should be 1/2 of the bolt diameter or flush with the nut; when connecting the valve, the nut should be placed on the side of the valve.

        B. Air duct angle steel flange

        1. After the flange is tightened, it should be tight and leak-free, the flange surface gap should be even, and the gasket should not protrude into the pipe or protrude out of the flange;

        2. The flange should be made with a smooth flange surface, equal diagonal lengths, and full welds;

        3. The flange bolt holes and rivets are evenly spaced and meet the specifications, and screw holes are provided at the four corners of the flange;

       4. When connecting flanges, the direction of the bolts should be uniform and the length should be consistent. The material of the bolts should correspond to the air duct; there should be no rust on the bolts after the flange connection.

      C. Air duct thin steel plate flange

      1. The flange should be vertical and closely attached to the air duct;

      2. Apply sealant to the inside and outside of the four corners of the air duct flange;

      3. The four corners of the flange are fixed with bolts, and a spring clip or jack screw is used in the middle. The spacing is ≯ 150mm, and the distance between the outer end and the edge of the air duct is ≯ 100mm.

      2. Welding connection

      A. Welding

      1. The stainless steel pipe welding interior is filled with argon for protection, and the weld seam and heat-affected zone are pickled and passivated after welding;

      2. Brazing of copper tubes must not be overheated (650-750℃), and any residual slag and other debris at the welding joint should be removed after welding;

      3. The appearance of the weld shall be inspected to ensure that there are no defects such as meat bites, slag inclusions, cracks, and splashes.

      B. Weld bevel

      According to the specification requirements, the groove is generally V-shaped, the groove angle is 60-75°, and the assembly gap is 2-3mm.

      C. Weld seam assembly

       The misalignment of the inner wall should not exceed 10% of the wall thickness and ≯2mm; the misalignment of the outer wall should not exceed 3mm.

   After the copper pipe is welded, when the solder is fully solidified but not completely cooled, use waste wire and clean water to scrub the flux left at the weld, and dry the waste wire to dry it. Then coat the welds with varnish one degree to prevent rust. After welding the stainless steel pipe, use a stainless steel brush dipped in acid paste to scrub the weld until it turns white and bright, then rinse it with clean water; then wipe it with passivation liquid, scrub it clean with cold water, rinse it with hot water and dry it.

       3. Pressure connection

       Clean the insertion port and mark the insertion depth. Insert the pipe to the specified depth, keeping the axis vertical. Use a special clamping tool to clamp the connector. After clamping, use a gauge to check whether the clamping size is in place.

       4. Threaded connection

    Thread processing is performed in 2-3 cuts. The threads should be clear, complete and smooth, without burrs or random threads. If there is any broken or missing wire, it shall not exceed 10% of the total number of thread threads. The threads should also meet the requirements of assembly tolerances and have a taper of 1/16 to prevent the threads from being too loose or too tight. Thread assembly, after tightening, expose 2-3 threads of the screw tail, remove excess filler, and paint the exposed threads with red lead to prevent rust. The red paint is applied with a consistent width, the coating is even, and there is no flow or leakage.

       5. Hot melt connection

    Clean the hot-melt parts and mark the hot-melt depth of the socket connection. Use a special hot melt machine to heat the connection parts according to the specified heating time. After heating, the joints are fused according to the specified pressure and time, and a uniform welding circle is formed at the joints.

       6. Socket connection

    Before connecting cast iron pipes, clean the socket and any debris that may affect the tightness of the interface, and correctly insert the rubber sealing ring. Insert and maintain the verticality of the two pipe sections according to the depth required by the construction standards.

      7. Groove connection

      A. Groove processing

      1. Check the size, roundness and manufacturing quality of the nozzle, which should meet the requirements for groove production;

      2. Process the groove in batches according to the specified time, and re-measure the depth and other dimensions of the groove;

      3. Groove processing must not damage the galvanized layer and inner coating of the pipe.

      B. Groove assembly

      1. Clean the pipe end, put on the rubber sealing ring, install the clamp and tighten the bolt;

      2. The center lines of the pipes at both ends of the trench are consistent, and the trench installation directions (fastening bolt positions) are consistent;

      3. Rigid joints should be used for straight pipe sections, and a flexible joint should be provided between every 4-5 consecutive rigid joints on the pipe section.