structure of pfa lined pump casing

Abstract

The invention discloses a PFA (Polyfluoroalkoxy) lining pump shell structure and aims at improving the production efficiency, reducing the manufacturing cost and the production reject ratio, making the improvement especially for a metal lining PFA pump shell structure, reducing the pump shell production cost and increasing the manufacturing yield. A metal shell lining PFA pump is used for conveying high-corrosivity chemical liquid, a metal shell is used for resisting the pump pressure and the piping load, and a PFA lining serves as a liquid receiving material to resist corrosion of liquid chemical. According to the improvement key point of the pump shell structure, the production bad factors of injection molding are reduced through the structure change, and the pump shell structure is characterized in that inlet shell lining PFA serves as a pumping inlet; scroll shell lining PFA is used for containing an impeller, collecting liquid generated after impeller acting and discharging the liquid through an outlet, and an inlet shell and a scroll shell are independently produced and then combined to form an integral pump shell so as to reduce the residual stress of injection molding.

Description

technical field [0001] The present invention relates to a PFA (Polyfluoroalkoxy, tetrafluoroethylene-perfluoroalkoxy vinyl ether copolymer, perfluoroalkoxy, soluble polytetrafluoroethylene) lined pump shell structure improvement, in order to reduce production costs Moreover, it improves the molding yield of large pump casings with pump inlet diameters above 80 millimeters (mm) or impeller diameters above 200 millimeters (mm), and enables the pump to have high reliability at a temperature of 200 °C. The invention improves the structure of the pump casing to reduce the structural stretch in the PFA molding process, reduce the residual stress, and improve the yield rate of the PFA lining of the pump casing produced by injection molding. Background technique [0002] Press, the general metal lined PFA (Polyfluoroalkoxy, tetrafluoroethylene-perfluoroalkoxy vinyl ether copolymer, perfluoroalkylate, soluble polytetrafluoroethylene) pump casing has been widely used in many chemical ...

AI Technical Summary

Problems solved by technology

[0023] (1) The manufacturing cost of transfer molding is too high and the production time is too long;

[0024] (2) Rotary molding cannot produce the scroll-shaped pump casing and the axial support frame integrated with the pump casing;

[0025] (3) The density of the PFA lining of the rotary forming pump casing is low and the thickness cannot be accurately controlled;

[0026] (4) The injection molding of PFA lining is not suitable for the production of large pump casings due to shrinkage stress;

[0027] (5) Injection molding including the shaft support frame will increase the residual stress, and it is not suitable for the production of large pump casings

[0028] The manufacturing cost is too high and the production time is too long by using the transfer molding method; if the rotary molding is used, the scroll-shaped pump casing and the axial support frame integrated with the pump casing cannot be produced accurately, and the thickness cannot be accurately controlled; the following will address the injection molding problem. Solutions, including the above-mentioned 4th and 5th points

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