RU193926U1 - Compressor piston with eccentric grooves - Google Patents

Abstract

The utility model relates to the field of compressor engineering, namely to pistons for reciprocating compressors, used mainly in the oil and gas industry. Compressed media (hereinafter referred to as the working medium) are mainly gases and / or mixtures thereof, for example, such as nitrogen, carbon dioxide, hydrogen, oxygen, methane, butane in the temperature range, mainly from 20 to 180 ° C, pressure range, mainly from 3 to 130 atm and / or differential pressure, mainly, up to 60 atm. The proposed piston consists of a rod with a thrust collar, a threaded nut for fixing the assembled piston of three parts to the rod, two lockless integral guide rings and two piston rings. From untwisting, the nut is locked with a cotter pin. For the correct coordination of the eccentric grooves, all the piston components are fixed to each other from rotation by pins. The grooves for the guide rings are made with eccentricity. A feature of this piston is the simplification of the manufacture and installation of lockless one-piece guide rings when assembling the piston, the increase in the duration of the piston guide rings (increase in the overhaul distance), the increase in the reliability of the piston assembly by balancing the inertial forces and moments in the opposed structure compressor.

Description

The utility model relates to the field of compressor engineering, namely to pistons for reciprocating compressors, used mainly in the oil and gas industry. Compressed media (hereinafter referred to as the working medium) are mainly gases and / or mixtures thereof, for example, such as nitrogen, carbon dioxide, hydrogen, oxygen, methane, butane in the temperature range, mainly from 20 to 180 ° C, s pressure range, mainly from 3 to 130 atm and / or pressure drop, mainly up to 60 atm.

The peculiarity of the use of pistons for reciprocating compressors in the modern oil and gas industry in Russia is that the working media containing fine particles in the form of metal dust, scale, oxide films, rust particles and other components is quite severely contaminated, which causes an increase in the wear rate of guides and sealing piston rings. Therefore, one of the approaches to ensure their effective operation in such conditions is measures aimed at increasing the life of the piston ring guides, the ability to quickly replace wear piston ring guides and simplifying the design of replaceable parts.

The level of technology.

A well-known composite double-acting piston (RF patent No. 157447 for utility model, F04B 53/14, 2015 [1]), which can be considered as an analogue, containing a rod with a thrust shoulder and made hollow and composite of two half-pistons, characterized in that the width of the first half-piston is greater than the width of the second half-piston, while grooves for piston sealing rings are made on the outer surface of the first half-piston.

The disadvantage of this analogue is the lack of guide rings that allow the piston to be operated in a horizontal cylinder position.

A compressor piston with an eccentric groove for guide rings is also known in international compressor engineering (US Pat. No. 5,052,275 to Horizontal reciprocating compressor with an eccentrically djustable piston therein Mayer Roland, Sulzer AG, F04B 53/14), which can be considered a prototype by the number of common features.

The disadvantage of this technical solution is that the guide rings of the piston are made in the form of separate segments, and this increases the complexity of manufacturing and installing the guide rings on the surface of the piston.

The technical problem solved by the proposed utility model is the elimination of the above disadvantages, and especially the simplification of the design of the guide rings and increase the life of their operation.

The essence of the claimed technical solution is that to increase the duration of the guide rings, the piston is executed with an eccentric displacement of the grooves for the guide rings relative to the outer diameter of the piston into which the one-piece lockless guide rings are mounted. The magnitude of the eccentricity of the grooves for the guide rings is selected so that the axis of the piston rises above the axis of the cylinder by the amount of allowable runout of the rod. For the installation of one-piece, lockless guide rings, the piston is made of three-piece components. In this case, for the correct coordination of the eccentric grooves, all the piston components are fixed to each other from rotation by pins.

Another advantage of the piston of the composite structure is the possibility of obtaining high precision surface dimensions (including internal) by machining, which allows to increase the reliability by balancing the inertial forces and moments in the opposed compressor design.

The technical result provided by the claimed technical solution is to increase the duration of the piston guide rings (increase in the overhaul distance), simplify the manufacture and installation of lockless integral guide rings during piston assembly, increase the reliability of the piston assembly by balancing the inertial forces and moments in the opposed compressor design.

The proposed method for changing the design of the piston rod will allow:

- increase the resource and maintainability of the piston assembly;

- increase the overhaul interval of the piston compressor;

- the use of one-piece lockless guide rings prevents the possibility of their operation as sealing piston rings.

The above essence is a combination of essential features of the claimed technical solution, ensuring the achievement of all the claimed technical results.

The claimed technical solution is illustrated by the drawing.

The figure shows the general view and composition of the compressor piston compound with eccentric grooves.

Implementation of a utility model.

The compressor piston contains a rod with a thrust collar (Figure, position 1), a threaded nut (Figure, position 2) for fixing the assembled piston (Figure, position 3) to the rod, two guide rings (Figure, position 4) and two piston rings (Figure , position 5). From untwisting, the nut is locked with a cotter pin (Figure, position 6). For proper coordination of the eccentric grooves, all the piston components are fixed to each other from rotation by pins (Figure, position 7).

It differs from the prototype in that the piston, made with eccentric grooves for the guide rings, is made up of three parts with the use of lockless, one-piece guide rings.

Work description.

The compressor piston is part of the cylinder-piston group of the compressor. Part of the stock is fixed in the crosshead. The piston components are mounted on the rod and fixed with a nut. When tightening the nut, the torque force is controlled.

During operation, the compressor piston performs longitudinal reciprocating movements.

When the piston moves from one extreme point to another extreme point, gas enters the cylinder working volume through the suction valve. When the piston moves backward, the gas is compressed and exits the cylinder through the discharge valve. Next, the suction-compression cycle is repeated.

To date, the company has already manufactured and tested prototypes of the compressor piston compound with eccentric grooves in accordance with the proposed utility model. The tests showed an increase in the service life of the guide rings of the piston by 10%.

The claimed technical solution is implemented using industrially produced devices and materials, can be assembled at any industrial enterprise and will be widely used in cylinder-piston units of reciprocating compressors.

Claims (1)

A piston made with eccentric grooves for the guide rings, made of three parts with the use of lockless one-piece guide rings.

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