One. What is a progressing cavity pump
The pump formed by two or three screw meshing together is called a screw pump. Screw pump is in all the pump products appear relatively late in a pump products, because it is the use of a or more with two of the intermeshing space volume change to achieve the effect of conveying liquid, so it is called a screw pump.
Screw pump is the use of screw rotation to suction discharge liquid. As a result of the screw pump each screw meshing and screw and liner wall close cooperation, between the screw pump suction inlet and outlet, will be divided into one or more sealing space. With the rotation of the screw and the meshing, the sealed space in a screw pump suction side develops, the liquid from the suction chamber seal in among them, and the suction chamber along the screw axial continuously goes on to the discharge end, will be closed in the space of the liquid discharge, like a nut in screw rotation being constantly move forward, this is stainless steel work of single screw pump, the liquid is sucked into the thread and surrounded by the pump shell after sealed space, when active screw rotation, screw pump seal volume under the extrusion of screw tooth screw pump pressure, and move along the axial direction. Because the screw is constant rotation, so the liquid flow is uniform.
Two. Disassembly steps of screw vacuum pump:
1. Before the screw vacuum pump is disassembled, the clearance of each part of the rotor is measured and recorded.
2. Try to avoid hammering with a heavy hammer. The parts removed shall not be hurt and shall be properly kept.
3. The screw vacuum pump is separated from the motor, and the medium is emptied (to prevent the motor and toxic medium from hurting);
4. Remove the discharge body of screw vacuum pump;
5. Remove the stator of screw vacuum pump, and press the moving shaft of the pump shaft steering wheel for assistance if necessary;
6. Remove the rotor and intermediate shaft;
7. Remove drive shaft and shaft seal;
8. Take out the screw vacuum pump bearing and positioning sleeve from the bearing seat; Make detailed records of replacement reasons and usage of parts that need to be replaced.
9. The screw vacuum pump that is not used for a long time should be treated with anti-rust treatment. The method is to smear the non-painted metal surface with anti-rust grease, including the shaft surface and the inner cavity of the packing shell, and to lubricate it.
Three, screw vacuum pump assembly matters needing attention:
1. Before the screw vacuum pump is reassembled, the parts must be cleaned and the burr polished.
2, mechanical seal installation should be careful, the end face of the friction pair should be clean and coated with grease, no gasket lining or sealing ring of the static sealing surface with "106" silicone rubber coating. Use clean, sealed rubber seals and apply vacuum cock grease. The sealing ring and surface of the screw vacuum pump relief valve shall not be coated with any grease.
3. Correct installation of bearings makes the shaft rotate flexibly and without jam and resistance;
4, shaft seal installation: packing and installation, should make the packing gland pressing bolt position in the shell installation window, easy to adjust the bolt wrench;
5. When assembling the universal joint of the drive shaft, check whether the sealing ring is damaged and fill the cavity with grease;
6. When installing the stator, smear the surface of the rotor and sub-cavity with lubricating oil, which is conducive to stator installation; Adjust the clearance of rotor parts according to clearance list.
7, discharge body pressure tightening time, nut tightening should be uniform - to;
8, installation assembly, coupling installation deviation: YS0.2mm, AS0.5 °. 9. Leak detection shall be carried out after all installed.
9. Test run and necessary performance test shall be carried out after reinstallation. It can only be installed and used after normal operation.
