RU2538371C1 - Operation of pump-compressor and device to this end - Google Patents

Abstract

FIELD: engines and pumps.

SUBSTANCE: pump U-like piston rod end chamber comprises gas damper composed by gas ply is periodically filled with gas from compressor head end chamber. This fill can occur in piston one double stroke. Pump-compressor consists of cylinder (1) with gas and fluid check valves accommodates U-like piston (6) dividing cylinder (1) into two parts, top compressor chamber (7) and bottom pump section (8). Float (9) divides said U-like recess into two parts, i.e. gas ply (10) and fluid chamber (11), and has ledge (12) to get, at fluid level increase in chamber (11), in contact with spring-loaded element (14) in valve (15) body to shut off flow channel (17). Device to retain valve (15) in open/close positions consists of spring-loaded balls (18) and two bores (19). Cylinder (1) cooling jacket (22) has bore (23) designed to direct forced liquid coolant via jacket (22). Gas ply (10) is retained in preset volume irrespective of gas content in transferred fluid and its solubility as well as operating conditions of the device (temperature, gas and fluid suction and delivery pressure, rpm, etc.).

EFFECT: higher operating performances.

3 cl, 4 dwg

Description

The invention relates to the field of pump and compressor engineering and can be used to create machines designed to compress and supply to the consumer simultaneously or alternately liquids and gases.

There is a known method of operation of a compressor pump, which consists in simultaneous or alternating compression of gas in a supra-piston compressor cavity and liquid in a sub-piston pump cavity and forcing liquid and / or gas to consumers (see, for example, USSR AS No. 1078126, MKI F04B 39/06, 07.03 .84, RF patent No. 118371, MKI F04B 19/06 from 07/20/2012).

There is also a known method of operation of a compressor pump, which consists in simultaneous or alternating compression of gas in an over-piston compressor cavity and a liquid with a layer of gas located above it in a under-piston pump cavity during reciprocating movement of the piston, and forcing liquid and / or gas to consumers (see, for example, RF patent No. 125635 for utility model, MKI F04B 19/06, 03/10/2013).

A disadvantage of the known methods is the impossibility of guaranteed ensuring the presence of a gas layer above the liquid located in the under-piston space, because due to the phenomenon of gas dissolving in a liquid, it gradually disappears in the sub-piston space, completely passing into the pumped liquid.

A device for implementing the known method comprises a cylinder with gas and liquid check valves and a piston dividing the cylinder into the upper compressor and lower pump cavities, the piston being U-shaped.

The objective of the invention is to ensure the presence of a layer of gas above the liquid in the under-piston space.

This technical result is achieved by the fact that with a decrease in the gas layer above the liquid in the subpiston cavity, this cavity is “temporarily” connected to the supra-piston cavity, and this connection can be made during one reciprocating movement of the piston.

The compressor pump for implementing the proposed method comprises a float located in the pump cavity dividing this cavity into a gas layer and a liquid cavity, a valve with a passage channel is installed in the piston body, which in the open state connects the compressor cavity to the pump cavity, and a device for fixing the valve to open and closed positions, the valve comprising an element in contact with the float in the vertical direction.

The invention is illustrated by the example of the piston pump-compressor, schematically shown in the drawings.

Figure 1 schematically shows a longitudinal section of a cylinder-piston group of the pump-compressor in the normal operating position.

Figure 2 shows the position of the elements of the cylinder-piston group with an excessively small volume of gas above the liquid in the pump cavity, when the float interacts with the valve and opens it.

Figure 3 shows the position of the elements of the cylinder-piston group during compression in the compressor cavity and filling the pump cavity with compressed gas.

Figure 4 shows the position of the elements of the cylinder-piston group, in which there is a process of completing the filling of the upper gas part of the pump cavity with compressed gas and closing the valve.

The compressor pump (Figs. 1-4) consists of a cylinder 1 with gas return (2 - suction, 3 - discharge) and liquid valves (4 - suction, 5 - discharge), in which a U-shaped piston 6 is located, separating the cylinder 1 in two parts - the upper compressor 7 and the lower pumping 8 cavity. The float 9 freely moving in a vertical plane relative to the piston 6 is located in the pump cavity 8 in the U-shaped depression of the piston 6 and divides this depression into two parts — the gas layer 10 and the liquid cavity 11. The float 9 has a protrusion 12, which, when the liquid level rises cavity 11 is in contact with a preloaded weak spring 13 element 14, made in the form of a pin mounted in the body of the valve 15 and passing through the groove 16 in the body of the piston 6. The valve 15 overlaps the passage channel 17, made in the form of holes and connecting when opened (lifting) of the valve 15, the compressor cavity 7 with the gas layer 10. The device for fixing the valve 15 in the open position (the valve is raised) and closed (the valve is recessed in the piston body 6) consists of spring-loaded balls 18 located on one line, perpendicular to the line of movement of the valve 15, and two grooves 19 in the body of the valve 15. Between the piston 6 and the walls of the cylinder 1 there is a gap 20, the seal 21 prevents leakage of fluid from the pump cavity 8 into the cavity of the drive mechanism (not shown conditionally). The liquid jacket 22 serves to cool the cylinder 1, the hole 23 is designed to direct the flow of pumped fluid through the jacket 22.

The proposed method of operation of the pump-compressor is as follows (figure 1).

During reciprocating movement of the piston 6, gas is sucked through valve 2 into the compressor cavity 7, is compressed in it and is pumped to the consumer through valve 3. At the same time, the liquid is sucked into the pump cavity 8 through valve 4, is compressed in it and is pumped to the consumer through valve 5. the liquid during injection flows through the jacket 22 (through the hole 23) and cools the walls of the cylinder 1, bringing the gas compression process closer to isothermal, which increases the efficiency of the compressor cavity 7.

Due to the presence of the gas layer 10 separated from the pump cavity 8 by the float 9, the process of expansion and contraction of the fluid proceeds smoothly, because the gas layer 10 performs the function of a damper or air hood and smoothes out sudden changes in pressure in the pump cavity 8 that occur when the direction of movement of the piston 6 changes. This contributes to the shock-free operation of valves 4 and 5, reduction of hydraulic and inertial losses, and makes it possible to increase the frequency of reciprocating motion piston 6 to the optimum inherent in piston compressors (from 750 to 1500 min ^-1 and above), which allows to improve the economic performance of the compressor cavity 7 and the pump-compressor as a whole.

In the process of compression and then injection of fluid (the piston 6 moves down) in the pump cavity 8 and its part of the cavity 11, the pressure increases, which leads to an increase in the liquid level in the cavity 11 and a decrease in the thickness of the gas layer 10 while increasing the pressure in it to the pressure in the cavity 8 and moving the float 9 up.

In the process of expansion and then suction of the liquid, the pressure in the cavity 8 and its part of the cavity 11 drops, the gas layer 10 expands, the pressure in it becomes equal to the suction pressure of the liquid in the cavity 8, the float 9 moves down.

Due to the fact that there are fluid overflows from the cavity 11 into the gas layer 10 and vice versa from the gas from the layer 10 to the liquid of the cavity 11 due to the leakage of the interface “piston 6 walls - the surface of the float 9”, gas from the layer 10 gradually dissolves in the liquid cavity 11 and is carried away in the process of pumping fluid. In this case, the amount of gas in the layer 10 gradually decreases, and therefore the level of the liquid in the cavity 11 increases and the float 9 rises higher and higher during the injection of the liquid.

With a certain loss of gas in the layer 10, the float in the process of compressing the liquid in the cavity 8 begins to contact the protrusion 12 with the element 14, which, thanks to the spring 13 and the spring-loaded balls 18, is held in the lowest position in the groove 16, and therefore the valve 15 remains closed shown in figure 1.

With an excessively large loss of gas in the cavity 10, its volume becomes unacceptably small to ensure the normal operation of the compressor pump, the liquid level rises too high in the process of pumping it in the cavity 11, and the float 9, abutting against the element 14, begins to sink into the liquid layer of the cavity 11 Due to the force of Archimedes, a sufficiently large buoyancy force 9 is generated in the direction of the element 14, which exceeds the force of the spring 13, and the fixing force of the balls 18, which leads to the release of the valve 15 and its opening during the stroke of the piston 6 bottom (2).

In this case, the gas layer 10 is connected through the holes 17 with the compressor cavity 7, in which, during the piston 6 downward, the gas is sucked in, the pressure in the cavities 7 and 10 are equalized. This state continues until the piston 6 moves down.

In the subsequent upward stroke of the piston 6 in the cavity 7, the gas is compressed and injected sequentially, and in the cavity 8, the suction process occurs with a pressure drop (Fig. 3). Due to the pressure difference in the cavities 7 (it is larger) and 8 (it is lower), the layer 10 is filled with a new portion of gas, which, due to the fact that the volume of the decreasing cavity 7 is larger than the volume of the internal space of the U-shaped piston 6, flows into the layer 10 under high pressure. In this case, the float 9 moves downward, displacing the fluid from the cavity 11 into the expanding cavity 8. This process ends when the piston 6 arrives at the top dead center (Fig. 4), when the valve 15 abuts against the valve plate, breaks into the fixing balls 18 and settles in the initial position, where it is again fixed by balls 18. The gas layer takes its original volume.

Then the construction work is repeated. The restoration of the gas layer 10 is performed in one double stroke of the piston 6.

Thus, the proposed method and device for its implementation allows for the entire duration of the pump-compressor operation to constantly maintain a gas layer 10 in a predetermined volume regardless of the gas content in the pumped liquid and the ability to dissolve it in this liquid, which can differ significantly from that of its different grades and brands, and depending on the operating conditions of the compressor pump (temperature, suction and discharge pressure of gas and liquid, speed, etc.).

Claims (3)

1. The method of operation of a piston pump-compressor, which consists in the simultaneous or alternating compression of gas in the supra-piston compressor cavity and fluid with a layer of gas above it in the sub-piston pump cavity during reciprocating movement of the piston, and forcing consumers with fluid and / or gas, characterized in that with a decrease in the gas layer above the liquid in the subpiston cavity, this cavity is temporarily connected to the suprapiston cavity. 2. The method of operation of the piston pump compressor according to claim 1, characterized in that the connection of the supra-piston cavity to the sub-piston cavity is performed during one reciprocating movement of the piston. 3. The pump-compressor for implementing the method according to claim 1, comprising a cylinder with check gas and liquid valves and a piston separating the cylinder into the upper compressor and lower pump cavities, the piston being U-shaped, characterized in that a float is placed in the pump cavity dividing this cavity into a gas layer and a liquid cavity, a valve with a passage channel is installed in the piston body, which in the open state connects the compressor cavity to the pump cavity, and the device for fixing the valve in the “open” position and "closed", wherein the valve comprises a contacting member with the float in the vertical direction.

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