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CN-122014599-A - Strong self-priming high-pressure external double-suction double-screw pump

CN122014599ACN 122014599 ACN122014599 ACN 122014599ACN-122014599-A

Abstract

The invention discloses a strong self-priming high-pressure external double-suction double-screw pump which comprises a pump body, wherein a group of screw pairs are arranged in the pump body, each screw pair comprises a driving screw and a driven screw, each screw comprises a rotating shaft, a left screw sleeve and a right screw sleeve which are fixedly arranged on the peripheries of the rotating shafts, the left screw sleeve and the right screw sleeve on each screw are made into a whole, the left screw sleeve and the right screw sleeve on each screw are provided with tooth grooves with the same shape, the screw directions of the left screw sleeve and the right screw sleeve are opposite, the surfaces of the tooth grooves are covered with wear-resistant rubber layers, and the left screw sleeve and the right screw sleeve on the driving screw are correspondingly meshed and matched with the right screw sleeve and the left screw sleeve on the driven screw. The screw pair in the invention adopts an integrated design, enhances the structural rigidity, enables the pump to bear higher working pressure, and simultaneously, the tooth-shaped groove of the spiral sleeve is covered with the wear-resistant rubber layer, thereby realizing the fine control of the meshing gap of the screw, greatly reducing the medium backflow and improving the self-priming efficiency and the volumetric efficiency.

Inventors

  • DENG KEFENG
  • HU CHENTAO
  • JIN XINTING
  • XIANG YIQUN
  • YUAN DAOXING

Assignees

  • 黄山众拓工业泵制造有限公司

Dates

Publication Date
20260512
Application Date
20260202

Claims (6)

  1. 1. The strong self-priming high-pressure external double-suction double-screw pump is characterized by comprising a pump body (8), wherein a group of screw rod pairs (1) are arranged in the pump body (8), each screw rod pair (1) comprises a driving screw rod and a driven screw rod, each screw rod comprises a rotating shaft, a left screw sleeve and a right screw sleeve which are fixedly arranged on the periphery of the rotating shaft, and the three screw rods are manufactured into a whole; The left spiral sleeve and the right spiral sleeve on each screw rod are provided with tooth-shaped grooves with the same shape, the screw threads of the left spiral sleeve and the right spiral sleeve are opposite in rotation direction, and the surfaces of the tooth-shaped grooves are covered with a wear-resistant rubber layer (17); The left spiral sleeve and the right spiral sleeve on the driving screw are correspondingly meshed and matched with the right spiral sleeve and the left spiral sleeve on the driven screw.
  2. 2. The strong self-priming high pressure external double-suction double-screw pump according to claim 1, wherein the tooth profile line of the tooth profile groove comprises a cycloid and an archimedes spiral line, and the cycloid is formed by taking one of the pitch circles of the spiral sleeve as a movable circle and taking one of the pitch circles of the other spiral sleeve as a fixed circle to make pure rolling, wherein a point on the outer circle corresponding to the movable circle is a locus formed by a swinging point.
  3. 3. The strong self-priming high-pressure external double-suction double-screw pump according to claim 1, wherein the thickness of the wear-resistant rubber layer (17) is 0.1-2 mm, the wear-resistant rubber layer and the tooth-shaped groove are fixed through hot vulcanization adhesion, and the wear-resistant rubber layer adopts ethylene propylene diene monomer rubber.
  4. 4. The strong self-priming high pressure external double-suction double-screw pump according to claim 1, wherein the depth of the thread profile of the profile groove is set to be 0.15-0.25 times of the pitch circle of the screw sleeve.
  5. 5. The strong self-priming high-pressure external double-suction double-screw pump according to claim 1, wherein the screw pair (1) is rotationally connected with the connecting plates (5) fixed on two sides of the pump body (8) through bearings, sealing rings (3) are arranged on rotating shafts on two sides of the screw pair (1) and are axially fixed through sealing covers (4) fixed on the inner sides of the connecting plates (5), double-spring framework oil seals (43) are arranged on one sides, far away from the sealing rings (3), of the sealing covers (4), and the double-spring framework oil seals (43) are arranged on the periphery of the rotating shafts, so that a mechanical sealing cavity is formed between the bearings and the corresponding spiral sleeves.
  6. 6. The strong self-priming high-pressure external double-suction double-screw pump according to claim 5, wherein the connecting plate (5) is provided with a vertical long hole (52) and a transverse communication hole (53) communicated with the bottom of the vertical long hole, the side wall of the sealing gland (4) is provided with a first through hole (41) and a second through hole (42) which are mutually vertically communicated, the first through hole (41) is communicated with the mechanical sealing cavity, and two ends of the second through hole (42) are respectively communicated with the first through hole (41) and the transverse communication hole (53), so that a flow passage structure with cooling lubrication and high-pressure air flow purging functions is formed.

Description

Strong self-priming high-pressure external double-suction double-screw pump Technical Field The invention relates to the technical field of material conveying pumps, in particular to a strong self-priming high-pressure external double-suction double-screw pump. Background The external double-suction double-screw pump is widely applicable to various industries such as petroleum, chemical industry, metallurgy, steel, electric power, ships, pharmacy, food, building materials and the like, has multiple applicable mediums, wide conveying range and complex application working conditions, which are incomparable with other pump products, and the characteristics also lead the series of pumps to have potential use and development prospects. The double-screw pump can be divided into an internal bearing and an external bearing, wherein the internal bearing is in a structure type, the bearing is lubricated by a conveying object, and the working cavity and the coaxial bearing of the double-screw pump in the external bearing structure are separated. For an external double-suction double-screw pump, after the medium conveyed enters from the inlet of the pump, the medium enters into the thread engagement space from the two ends of the screw sleeve, and the liquid is pumped by using two mutually engaged screws. The driving screw with one end extending out of the pump is driven by the prime motor, the driving screw and the driven screw are provided with threads with different rotation directions, the screw is closely attached to the pump body, and the driven screw is driven by the driving screw through the synchronous gear to jointly form a screw pair. The existing double-screw pump in the market cannot bear high pressure, the main reason is that the rigidity of the screw pair is insufficient, and the main reason is that the structure is unreasonable, including the connecting plate is too wide and the screw thread is too deep. The double screw pump is used as a positive displacement pump, and theoretically, the suction chamber and the discharge chamber in the pump should be closely separated, so that the outer circle surfaces of the pump body and the screw rod and the gaps between the screw rod and the screw rod should be as small as possible, and meanwhile, the screw rod and the pump body, the screw rod and the screw rod form a sealing cavity mutually, so that the sealing is ensured, otherwise, liquid may flow back from the gaps. However, due to the limited meshing clearance between the threads of the screw, too small a clearance can cause biting or even seizure during operation of the pump, thereby rendering the pump inoperable, and the clearance is large and directly affects the self-priming performance of the pump. How to reduce the screw flight clearance as much as possible is a problem that needs to be addressed in the prior art. Therefore, the external double-suction double-screw pump with strong self-suction and high pressure is provided. Disclosure of Invention The invention aims to provide a strong self-priming high-pressure external double-suction double-screw pump to solve the problems that in the prior art, screw thread meshing clearance is difficult to control and screw pair rigidity is insufficient. The invention can be realized by the following technical scheme that the strong self-priming high-pressure external double-suction double-screw pump comprises a pump body, wherein a group of screw pairs are arranged in the pump body, each screw pair comprises a driving screw and a driven screw, each screw comprises a rotating shaft, a left screw sleeve and a right screw sleeve which are fixedly arranged on the periphery of the rotating shaft, and the three screws are manufactured into a whole; The left spiral sleeve and the right spiral sleeve on each screw rod are provided with tooth-shaped grooves with the same shape, the screw threads of the left spiral sleeve and the right spiral sleeve are opposite in rotation direction, and the surfaces of the tooth-shaped grooves are covered with wear-resistant rubber layers; The left spiral sleeve and the right spiral sleeve on the driving screw are correspondingly meshed and matched with the right spiral sleeve and the left spiral sleeve on the driven screw. The invention further technically improves that the tooth profile line of the tooth-shaped groove comprises a cycloid and an Archimedes spiral line, and the cycloid forming process comprises the steps of taking the pitch circle of one spiral sleeve as a movable circle, and taking one point on the outer circle corresponding to the movable circle as a swing point to form a track when the pitch circle of the other spiral sleeve is used as a fixed circle to perform pure rolling. The wear-resistant rubber layer is 0.1-2 mm in thickness, is fixed with the tooth-shaped groove through hot vulcanization adhesion, and is made of ethylene propylene diene monomer rubber. The invention further technically improves that the depth of