RU2168068C1 - Horizontal multi-sectional centrifugal pumping unit - Google Patents

Abstract

FIELD: manufacture of pumps; centrifugal pumps for injection of water into beds in oil production. SUBSTANCE: pumping unit includes pump sections with shafts, inlet unit including housing, cylinder which is located axially with shaft arranged inside this cylinder, end seals and bearings with support, clutch, electric motor and frame. Adjacent ends of shafts of first section of pump and inlet unit are provided with couplers made in form of screws with cylindrical heads. Screws are driven into shafts. Bearing face of head of one of screws is made at angle α which is open towards its threaded section. Head of other screw is provided with blind cylindrical recess. End wall is also made at angle α on side of head which is open away from threaded section: 170<α<180. End sections of both heads are provided with sector slots and projections which are engageable and are locked by splined clutch. Cylinder and bearing support are provided with straightway passages forming cooling chamber together with shaft. EFFECT: reduced labor consumption due to avoidance of inlet unit of precision bearings, reduction of sealing members, avoidance of oil piping system and end seal cooling pipe line. 2 cl, 4 dwg

Description

 The invention relates to the field of pump engineering, in particular to centrifugal pumps for pumping water into reservoirs during oil production. It can also be used in pumping installations for oil production with a surface drive to connect the rotating shafts to the shaft of a submersible pump.

 A pump assembly is known, comprising a housing located in a container with a pumped liquid and fixed on its column, an impeller located in the housing, connected to an engine located outside the tank by means of a shaft shaft consisting of shafts connected by compensating couplings and mounted in sliding bearings installed in column connectors. Moreover, the shafts are equipped with embedded elements with shanks in contact with the centering spheres and union nuts (1,2).

The main disadvantages of this design include:
- the high complexity of manufacturing parts connecting adjacent shafts, due to the complexity of the implementation of spherical surfaces at the contact points;
- significant transverse dimensions of the connected parts, making them unsuitable for use in pumps with small transverse dimensions, for example, in oil submersible centrifugal pumps for oil production.

 Also known is a horizontal multi-section centrifugal pumping unit of the company "REDA", consisting of multi-section pumps rigidly articulated by their bodies, and by shafts - with the possibility of slight longitudinal displacement using splined couplings, an input unit for introducing the pumped liquid into the first section of the pump, a coupling connecting the shaft input node with the shaft of the electric motor and the frame. The input node consists of a housing made in the form of a tee, in which a cylinder is axially located for placement of a drive shaft in it on precession rolling bearings and a mechanical seal (3).

The disadvantages of this design include:
- the high complexity of manufacturing the input unit, dictated by the presence of precession rolling bearings, high-precision seats for them, a large number of o-rings and seals, adjusting devices, a cooling system and oil supply to the cavity of rolling bearings and a system for supplying pumped fluid to the cavity of the mechanical seal;
- high operating costs due to the need to attract highly qualified specialists for repair, commissioning and operation and the need for additional energy costs for cooling and supplying oil to the cavity of the rolling bearings and to compensate for the axial force per shaft end.

 The objective of the invention is to reduce the complexity of manufacturing a pumping unit and operating costs.

 This problem is solved by the described horizontal centrifugal pumping unit containing pump sections with shafts, an inlet assembly including a housing, an axially located cylinder, inside of which there is a shaft, a mechanical seal and bearings with a support, a coupling, an electric motor and a frame.

What is new is that the adjacent ends of the shafts of the first section of the pump and the inlet assembly are equipped with couplers made in the form of screws with cylindrical heads screwed into the shafts, the bearing face of the head of one screw being made with an angle α satisfying 170 <α <180 and disclosed in the side of its threaded section, and in the head of the other screw there is a blind cylindrical undercut, and its end wall located on the side of the head is also made with an angle α satisfying the condition 170 <α <180 and opened opposite to the threaded part weaving side;
on the end sections of both heads in the area between the surfaces of a blind cylindrical undercut and a screw, sector grooves and protrusions with the same central angle and the same number are made; the protrusions of one screw head are in contact with the protrusions of the other head and are fixed in this position by a spline sleeve coupling; The axially located cylinder and the bearing support of the input unit are made with passage channels and form a cooling chamber with the shaft.

 Also new is that the passage channels in the axially located cylinder are made at its end from the side of the mechanical seal.

 In FIG. 1 shows a General view of the proposed pump installation.

 In FIG. 2 is a longitudinal section of the input node.

 In FIG. 3 - the connection node of the shaft of the last stage of the pump with the shaft of the input node.

In FIG. 4 is a cross section along AA of FIG. 3
The installation includes (see Fig.) The sections of the pumps 1, rigidly connected to each other by means of fasteners 2, a clamp, 3. clamps 4, an input unit 5 with a suction pipe 6, a coupling 7, a discharge pipe 8, an electric motor 9 and a frame 10 The input node 5, in turn, consists of (see Fig. 2) of the housing 11 with the inlet pipe 12 with a cylinder 13 axially located inside the housing with passage channels 14 on the side of the mechanical seal, the shaft 15 installed in the support 16 and in the cover 17 on bearings of a mechanical seal 18 and a joint assembly 19 last pump stage shaft 1 with the shaft 15.

 The support 16 has passage channels 20, and the cylinder 13 together with the shaft 15 and the cover 17 form a cooling chamber "b".

 The node 19 (Fig. 3) includes couplers 21 and 22, made in the form of screws screwed into the shaft of the last stage of the pump 1 and shaft 15 of the input node 5. The screws have cylindrical heads, the bearing face of the head of one screw is made with an angle α, satisfying condition 170 <α <180 and opened towards its threaded portion, and a blind cylindrical recess 23 is made in the head of another screw, and its end wall located on the side of the head is also made with an angle α satisfying condition 170 <α <180 and open opposite to the threads Vågå portion side. On the end sections of both heads, enclosed between the diameters "D" and "d", sectorial grooves 24 and protrusions 25 are made in the coupling 21, and sectorial grooves 26 and protrusions 27 coinciding in the drawing with the grooves 24 are made in the coupling 22. Grooves and protrusions in both heads are made with the same central angle and have the same amount. The protrusions of one screw head are in contact with the protrusions of the other head and are fixed in this position by a spline sleeve coupling 28.

 Installation works as follows.

 The pumped liquid, passing through the suction pipe section 6, enters the cavity "a" of the inlet 5, from which part of the flow through the passageways 14 of the axially located cylinder 13 is directed into the cavity "in" to cool the mechanical seal 18. Then, passing the cavity "in" , the flow is mixed with the main flow directed to the suction cavity of the first section of the pump 1. In this case, the forces arising from the pressure on the end of the shaft 15 are completely transmitted to the hitch 21 and create tensile stresses in the hitch 21 and 22, eliminating s design of bearings for the thrust.

Application of this technical solution will allow:
- reduce the complexity of manufacturing the input node of the installation, due to a significant simplification of its design, achieved in turn by fixing its shaft relative to the shaft of the first stage of the pump in the longitudinal direction;
- reduce operating costs, due to the exclusion of precession bearings from the input assembly design, the reduction in the number of sealing elements, the elimination of the oil pipe system and the mechanical seal cooling pipe system.

 Information used.

 1. A.S. N 1649120, MKI F 04 D 13/08, 1991. Analog.

 2. A. p. N 1800120, MKI F 04 D 13/08, 1993 (dependent on a.s. N 1649120). The analogue.

 3. Catalog material of the company REDA ", 1998 (Reda Pump Company Monctief Oil international, Jnc, 14450, TC Jester Saite 222 Houston Texas 77014) (Drawings on 3 sheets are attached). Prototype.

Claims (2)

1. A horizontal multisectional centrifugal pump installation comprising pump sections with shafts, an inlet assembly including a housing, an axially arranged cylinder with a shaft inside, an end seal and bearings with a support, a coupling, an electric motor and a frame, characterized in that the adjacent ends of the shafts are first sections of the pump and inlet assembly are equipped with couplers made in the form of screws with cylindrical heads screwed into the shafts, the bearing face of the head of one screw being made with an angle α satisfying 170 ^o <α <1 80 ^o and opened towards its threaded section, and in the head of another screw there is a blind cylindrical undercut, and its end wall located on the side of the head is also made with an angle α satisfying the condition 170 ^o <α <180 ^o and opened in the opposite direction threaded section side, on the end sections of both heads in the area between the surfaces of the blind cylindrical undercut and screw, sector grooves and protrusions with the same central angle and the same number are made, the protrusions of one screw head are in contact with by the protrusions of the other head and fixed in this position by a spline sleeve coupling, the axially located cylinder and the bearing support of the input node sliding are made with passage channels and form a cooling chamber with the shaft.  2. The horizontal multi-section centrifugal pumping unit according to claim 1, characterized in that the passable channels in the axially located cylinder are made at its end from the side of the mechanical seal.

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