Novel tooth profile of oil gas-water mixed transportation two-screw pump

Abstract

The invention discloses a novel tooth profile curve of an oil gas-water mixed transportation two-screw pump. The novel tooth profile curve is composed of A, B, C, D, E, F, G and H on the cross sectionof a screw, wherein F is located on the pitch diameter R2 of a tooth surface, C, D and E are located on a root circle, and G, H and A are located on an addendum circle with the radius R3; a curve defined by A and B is an arc line with the radius R1 and is tangent to the addendum circle, a curve defined by B and C is a cycloidal envelope line with the arc line as the base line, a curve defined byG, H and A is an arc of the addendum circle, a curve defined by F and G is an involute line, and a curve defined by E and F is a cycloidal envelope line with the involute line FG as the base line; andthe radius R1 of the arc line and the radius R3 of the addendum circle meets the relation 0.03R3<=R1<=0.04R3. The novel tooth profile curve has the beneficial effects that the sealing tooth profile curve has good wear resistance, so that an ideal sealing effect is achieved when the screw using a tooth profile adopting the curve is used for oil gas-water mixed transportation, and good wear resistance is ensured.

Description

Technical field [0001] The invention relates to a twin-screw pump, in particular to a new tooth profile based on the screw of the twin-screw pump with oil, gas and water mixed transmission. Background technique [0002] In the prior art, the tooth profile of the screw used for the oil-gas-water mixed transmission twin screw pump is divided into two types, namely, non-sealed profile and sealed profile. The former such as trapezoidal profile, rectangular profile, A-shaped profile, B-shaped profile and symmetrical elongated cycloid profile and so on. These twin-screw profile lines are non-sealed profile lines. When the tooth profiles of the two screws mesh with each other, the volume cavity formed by the driving screw, the driven screw and the inner hole of the pump casing is not a completely closed "sealed cavity". Its volumetric efficiency is low, and it cannot be adapted to long-distance pipeline transportation, especially when oil-gas-water is mixed, it cannot adapt to changes ...

AI Technical Summary

Problems solved by technology

The profiles of these twin-screws are all non-sealed profiles. When the tooth shapes of the two screws mesh with each other, the volume cavity formed by the driving screw, the driven screw and the inner hole of the pump casing is not a completely closed "sealed cavity". Its volumetric efficiency is low, and it cannot adapt to long-distance pipeline transportation, especially when oil, gas and water are mixed, it cannot adapt to changes in convective flow and gas content; and the sealing profile, that is, a single cycloid curve, can achieve strict sealing. However, due to the sharp angle of the formed sealing line, it is affected by hard solid impurities such as sand particles during the mixed transportation of oil, gas and water, and the sealing line will be worn soon, resulting in a decrease in the volumetric efficiency of the pump.

Images