HRP20100273A2 - Hydraulic axial piston control valve and its application - Google Patents

Abstract

The present invention relates to a hydraulic axial piston control valve with a linear position transmitter consisting of a valve body (1) and a central part (2) around which the fluid flows in the open state of the valve, a hydraulic cylinder (3) with a piston (4) and a connecting rod (5) to which the regulating piston (12) of the valve is firmly attached. The linear position sensor (8) is placed in the hydraulic cylinder (3) and in the electric version of the invention, a sensor with a magnetostrictive waveguide (20) is used. The subject invention also relates to the use of the linear response of such a valve for regulation purposes and with different means of drive; such as electro-hydraulic drive, pneumatic drive or autonomous drive that uses the energy of the fluid flowing in the pipeline.

Description

The field of technology

The subject invention relates to a hydraulic axial piston control valve. This invention belongs to the field of valve technology in which at least one component of the movement of the valve part that participates in opening or closing the valve is perpendicular to the closing surface, and where said valve part is placed in the main current of the fluid flow in such a way that said fluid flows through said regulating part while valve open.

The subject invention also relates to the application of such a valve in such a way that it is controlled with or without an external energy source.

Technical problem

Hydraulic axial piston control valves are used in systems where there are large pressure differences and large flows that need to be adjusted according to the needs of consumers, and they are often installed in very inaccessible places.

For a piston control valve, it is necessary that it can be completely incorporated into the pipeline at any position and location. Depending on the place of installation and regulatory requirements, the valve, in addition to reliability, must ensure accuracy, speed, linearity and repeatability of the formation of fluid flow through the valve. It is of particular importance that the construction of the valve should be such as to avoid: damage of a cavitation nature, noise during operation and vibrations, and the valve itself should be resistant to hydraulic shocks in the system.

The basic technical problem that is solved by the subject invention is the reliable detection and reporting of valve opening, more precisely the position of the control piston of the control valve, in a linear manner.

Another technical problem that is solved by the present invention relates to the use of the linear response of such a valve for regulation purposes with different means of drive; such as electro-hydraulic drive, pneumatic drive or autonomous drive that uses the energy of the fluid flowing in the pipeline. Detecting valve opening must be reliable and fast and preferably linear.

The third technical problem that is solved by the present invention relates to the use of the valve according to the invention in the so-called autonomous drive and in the case of transport of dirty and aggressive fluids such as rain, sewage or sea water, without the influence of such fluids on reliable control.

State of the art

The state of the art of axial-piston control valves described in the patent literature is very rich. The patent published as GB532848 (R.A. Blakebourgh and F.A. Klouman) from 1939 teaches the construction of an axial-piston valve that is installed in the stream of fluid flow, where the flow regulation is done by a piston that comes out of the housing and that actually reduces the cross-section through its diameter which fluid passes. The piston itself is moved by a mechanical gear transmission. The basic difference compared to the present invention is the actuation method of the valve piston. In the invention in question, the actuation of the regulating piston is hydraulic, and in this state-of-the-art document it is mechanical. Also, there is no indication of the possibility of knowing the exact position of the piston in this invention from the state of the art - which makes the solution itself unsuitable for auto-regulation purposes. The regulation speed is slow due to the mechanics used, and the safety system (eg automatic closing/opening) does not exist.

The technical solution described in the German patent application DE3829726 (J.E.H. Waldenmaier) from 1988 shows the use of an axial-piston control valve in the process of mechanical fluid flow regulation. Namely, by regulating the feedback using the pressure of the fluid in the pipeline, an external mechanism is started that moves the position of the piston inside the valve in a purely mechanical way - by means of the crankshaft. The mentioned state-of-the-art system has a relative reproducibility of behavior, and the actuation of the valve piston itself in a purely mechanical way makes this solution, unlike the subject invention, more complicated for use and maintenance in said difficult places for installation.

The document published as patent US 4,681,130 (AR-KAL Plastic Products) from 1986 teaches the construction of an axial-piston valve that is installed in a stream of fluid flow and whose flow regulation is regulated by a piston that is extended or shortened from a housing that obstructs the fluid. The position is regulated by hydraulic connection lines and the entire valve's dimensions correspond to the dimensions of the pipeline in which it is installed. According to the inventor, this solution is particularly suitable in cases where hydraulic shocks occur in the system. It differs from the subject invention in terms of the construction of the hydraulic activation and the method of "pulling out" the regulating piston, as well as in the absence of a safety system. Furthermore, the discussed technical solution does not have a built-in piston position sensor, so it is not suitable for use in an automatic fluid flow control system with a feedback connection.

International patent application PCT/IL96/00109 (TAVOR, Elhanan) from 1996 adopted and published as two EP patents EP0854992B1 and EP1205697B1 teaches a construction solution that is closest to the solution given according to the subject invention. Regulation of the position of pulling the piston out of the part that is being flowed by the fluid is done hydraulically and with the help of a spring mechanism which, in case of loss of pressure in the hydraulic part, acts on the piston with sufficient force to keep the valve closed - thus solving the safety part of the problem. In this technical solution, unlike the subject invention, there is no indication of the possibility of installing a piston position sensor that would reliably indicate the state of the valve opening, i.e. the position of the regulating piston. That said, the technical solution is not suitable for use in the system of automatic regulation of fluid flow with feedback, so-called. intelligent control valves. Apart from the above, the solution from PCT/IL96/00109 is not suitable for the construction of larger valve diameters and higher working pressures, it is sensitive to the flow of dirtier fluids due to the way the regulating piston is guided and the sensitivity of the sealing surfaces to abrasion and other damages.

The application of the valve for regulatory purposes is shown, for example, in the American patent published as US 6,263,905 (YOKOTA Hiroshi; YOKOTA Shingo) which teaches various autonomous ways of controlling the valve, which in its construction and properties is different from the valve according to this invention, and the autonomous drive is not applicable in use with dirty and aggressive fluids.

The essence of invention

The subject invention solves earlier technical problems in such a way that, unlike known solutions:

- it has an electric or hydraulic linear transmitter of the position of the regulating piston, which is located inside the hydraulic cylinder of the central part of the valve;

- that the movement of the regulating piston is defined by the longitudinal guides of the piston located on the inside of the central part of the body; and

- that the regulating piston is equipped with grooves and holes for hydrostatic relief of the regulating piston.

The regulating piston has a spring in its head which, when compressed, has enough elastic energy to always set the regulating piston in a position to completely close the flow of fluid through the valve in the event of a loss of pressure in the hydraulic channels. This improves the safety aspects of the functioning of the subject invention.

Description of the drawing

One of the possible ways of implementation and application of the subject invention is shown in drawings 1-29.

Drawing 1 - shows the construction of the hydraulic axial-piston control valve in a spatial view with a partial internal section so that the arrangement of all important functional parts can be seen.

Drawing 2 – shows a section of the control valve in the part that does not pass through the load-bearing ribs of the central part of the body.

Drawing 3 – shows a spatial representation of the electric position transmitter as it is installed in the axial-piston control valve.

Drawings 4-29 - show the method of using the hydraulic axial-piston control valve for control purposes.

Detailed description of the implementation of the invention

As mentioned before, the primary purpose of the hydraulic axial-piston control valve (hereinafter referred to as the valve) according to this invention is to: reliably, accurately, quickly, linearly and repeatably regulate the position of the control piston of the valve within its stroke while minimizing vibration and noise , and to avoid cavitation damage to the structure of the valve itself when using such a valve. Its use is particularly suitable as a control valve for flow and pressure regulation in water, air, gas and oil transport systems. Also, its construction makes it ideal for: commissioning of pumps, quick filling and emptying of reservoirs and dam outlets, turbine operation management; as a regulatory, measuring, shut-off and safety element in pipelines and water supply networks; for the prevention of hydraulic shocks; as a control valve of test stations in the transport of natural gas and in general in the flow regulation segment of various fluids.

The valve according to the subject invention, due to its dimensions of the external body (1), is such that it can be easily installed as an element of a pipeline in which it should perform a given function, for example, to regulate the flow of fluid. Said valve body (1) incorporates all other valve elements and is the only one visible when the valve is installed as a pipeline element. Inside said body (1) is the central part (2) of the valve (drawing 2), which is connected to the body (1) by ribs (16). The number of ribs (16) is optimal considering the hydrodynamic resistance of the fluid flow and the mechanical stresses of the construction of the valve itself. The valve body (1) and the central part (2) are made of materials that are standardly used in this type of valve and are known in the state of the art.

Fluid flows around the central body (2) and ribs (16) when the valve is in a certain open state. Inside the body (2) there is a hydraulic cylinder (3). Pressure fluid, usually hydraulic mineral oil, is supplied to the hydraulic cylinder (3) under pressure through bores - hydraulic channels (17) - located inside one or more ribs (16), which pushes the piston (4) and thus the regulating piston (12). of the valve itself attached to the piston (4). The hydraulic cylinder (3) is closed by the head (10) of the hydraulic cylinder. The body of the hydraulic cylinder (3) is preferably circular on the outer circumference and has grooves with seals and radial holes for the passage of compressed oil to the very piston (4) of the hydraulic cylinder (3). On the connecting rod (5) of the hydraulic cylinder (3), the regulating piston (12) is tightened with an external nut (13).

The regulating piston (12) has radial grooves or holes on it for balancing the pressures. Grooves and/or holes allow the working fluid to enter the space behind the face of the regulating piston (12) (in drawing 2, it is the space with the spring (6)) and thus the pressure in front of the face of the regulating piston (12) and behind the face, i.e. in the area of the regulating piston (12) should be the same. Such construction minimizes the force of starting the piston (12).

For large nominal valve diameters (Φ > 300 mm), it is not possible to tighten the regulating piston (12) to the piston rod (5) with only the external nut (13), but it is necessary to replace the connection with the nut with a joint connection, in a manner known in the state of the art. Such a connection enables small movements of the regulating piston (12) in the direction perpendicular to the movement of the connecting rod (5), without transmitting forces or moments to the connecting rod (5).

The piston (12) is guided by longitudinal guides (9) fixed on special ribs on the inside of the central part (2), as is known in the state of the art. In addition, additional guidance and reduction of vibrations is contributed by the guidance of the piston rod (5) of the hydraulic cylinder (3) itself. It is clear that the guiding of the control piston (12) through the central part of the part (2) of the valve body can be solved in any of the ways known in the state of the art, but the solution with guides seems the simplest for safe and reliable operation.

For small nominal valve diameters (Φ < 300 mm), it is also possible to make a version of the control piston (12) without guides (9), because in this case the piston rod (5) itself can dimensionally take over the piston (12) and withstand any forces perpendicular to the direction of the regulating movement of the piston (12).

In the first variant of the present invention, a spring (6) is placed on the outside of the hydraulic cylinder (3), which always pushes the regulating piston (12) into the closed position of the valve (1). Said spring (6) rests on one side on the hydraulic cylinder (3), and on the other side on the bottom of the regulating piston (12). The spring (6) plays the safety role of quickly returning the piston (12) to the closed position in the event of a "failure" of the hydraulic piston drive. In this variant of the invention, of crucial importance for correct and simple functioning are the previously described grooves/holes on the regulating piston (12) for balancing the pressures behind and in front of the piston face (12). Thus, the elastic force of the spring does not have to overcome the force of the output pressure of the fluid on the face of the regulating piston (12) when closing the valve.

In another variant of the subject invention - which is not shown in detail in the drawings - the action of the spring (6) is replaced entirely by the energy drawn from a source of pressure fluid (27) to drive the hydraulic cylinder (3). Such a solution is necessary in constructions of control valves with large nominal diameters, where the accumulated elastic energy of the spring (6) would not be sufficient to effectively perform its safety function of closing the valve in all operating modes. In this variant of the invention, the said construction instead of the spring (6) has additional hydraulic channels (17) for pressure control and "behind" the piston (4), in the chamber C2 on the regulation schemes. In the schematic representation given in drawing 4, the location of the chamber C2 can be seen with the already existing control of the chamber C1 of the hydraulic cylinder (3) which is also present in the first variant of the invention.

The third variant of the subject invention - which is also not shown in detail, is a combination of the first and second variants of the subject invention. In this variant, the action of the spring (6) is further enhanced by the energy drawn from a source of pressure fluid (27) to drive the hydraulic cylinder (3), the position of the piston (4) is controlled on the one hand by the control of the chamber C1 of the hydraulic cylinder (3) and on the other hand by controlling the pressure in chamber C2 supported by the elastic energy stored in the spring (6).

In all three embodiments of the subject invention, special attention is paid to the problem of sealing. The sealing of the regulating piston (12) in the closed position is done by means of the seal (11) located in the central part (2) of the valve and the seal (14) located in the outlet part (15) of the valve body. Sealing in the open position or in some intermediate position is not necessary because the fluid flows through the regulating piston and thus, as stated above, hydrostatically relieves the regulating piston (12) of the valve. In addition, this constructive feature allows that said seal (11) is not exposed to any wear, or only minimal wear, during the regulating stroke. It is not particularly emphasized here, but it is clear to a person skilled in the art that the number and arrangement of seals (11) and (14) can be arbitrary as long as they provide the desired technical sealing effect in the closed state of the valve.

In all three variants of the invention, signaling during control of the position of the piston (4) inside the hydraulic cylinder (3), and thus also the position of the regulating piston (12), is done by a linear position transmitter (8) centrally located in the hydraulic cylinder (3).

According to the subject invention, it is possible to use two different types of linear position transmitters - hydraulic and electric - considering the type and method of application of the subject invention.

By the term "electrical position sensor" here we mean a position sensor that, regardless of the physical method of sampling the position of the regulating piston (12), expresses it as a measurable electrical quantity. By the term "hydraulic position transmitter" here we mean such a position transmitter where the position of the regulating piston (12) manifests itself as a change in some of the mechanically measurable quantities, for example the volume or pressure of the fluid in the hydraulic line connected to such a position transmitter.

There are different types of electric linear position transmitters and the physical basis of the operating mode, but certainly one of the better choices that is used in practice is the magnetostrictive position transmitter. In the subject invention, other donors known in the state of the art can be used.

A magnetostrictive linear transducer as used in one aspect of the present invention is well known in the art. The principle of operation can be seen, for example, in patent US 4,970,464 and in the associated description of the prior art of the same document. The construction of such a position transmitter is shown in drawing 3 and consists of a transmitter head (8) with associated built-in electronic circuitry and a magnetostrictive waveguide (20), which is sometimes called a probe.

Drawing 3 shows such a linear magnetostrictive transducer with a magnetostrictive waveguide - probe (20) and a permanent magnet (21) (drawing 1) attached to the piston (4). At the position of the piston (4), i.e. the built-in permanent magnet, an interaction of the magnetic fields of the magnetostrictive waveguide and the permanent magnet occurs, which can be detected very precisely. The difference between the time of sending and receiving, i.e. the reading of the wave disturbance, measures the distance (19), i.e. the absolute position of the piston (4) in relation to the hydraulic cylinder (3), and thus indirectly the position of the regulating piston (12) in the central part of the body (2) of the valve (1).

The observed time response - i.e. the gap (19) - is converted into a linear electrical quantity in the position transmitter (8) itself, and as an easily measurable electrical signal quantity (eg voltage or modulated current signal) can be led by wires through the hole (18) further to the control valve processor (28) for the analysis of the relevant signal. Alternatively, already existing hydraulic channels (17) can be used for guidance, but then additional sealing problems arise. This placement of the linear position transmitter (8) enables immediate and immediate monitoring of the position of the regulating piston (12), and also serves to check the response of the piston body system (4) to hydraulic impulses (commands) sent through hydraulic channels (17).

In addition to linear electric position transmitters (8), position transmitters of special designs can be installed, as well as non-linear position transmitters, but their use requires additional adjustment of the actual state of the valve and the actual state of such a position transmitter through numerical adjustments.

If it is necessary to precisely guide the behavior of the valve (1), that is, the control piston (12), the data collected from the position sensor (8) can be additionally numerically processed in the processor of the control valve (28).

In the state of the art, "hydraulic" position transmitters are also known, the hydraulic output of which can be connected either to appropriate hydraulic amplifiers in order to control the valve, or to be connected to analog displacement indicators that only show the open state of the valve. The way it works is well known in the state of the art, using Pascal's law. Such position transmitters usually consist of a hydraulic piston, a hydraulic cylinder and a hydraulic line. The hydraulic piston can be attached to the movable (measured) part, which in our case is the piston (4), while the cylinder of such a hydraulic position transmitter is at rest. A change in distance (19) generates a linear volume change in the hydraulic line of such a position sensor. According to the subject invention, such position transmitters are most often used in autonomous mode of operation, without an external energy source, mainly for external signaling of the open state of the regulating piston (12) of the valve. According to its construction, the hydraulic position transmitter (8) must be such that it does not "burden" the operation of the control cylinder (3) and piston (4) of the valve, and at the same time it must be able to fit dimensionally into the space intended for the installation of the electric position transmitter described earlier. The hydraulic line of the said hydraulic position transmitter can be appropriately routed through the bore (18) to the hydraulic amplifier or the analog status indicator of the regulating piston (12).

In the case of smaller nominal valve diameters (Φ < 300 mm), the attachment of the hydraulic cylinder (3) to the central part (2) of the valve body and the closing and protection of one of the previously mentioned position transmitters (8) from the transport fluid flowing through the part (2) is performed with a cover (7) designed to represent as little resistance as possible to fluid flow and to reach the transmitter (8) in the simplest possible way in case of need. For larger nominal valve diameters, the hydraulic cylinder (3) is attached to the central part (2) with a special nut, and the cover (7) is attached to the central part (2) with special screws.

A valve designed in this way enables the fulfillment of all the goals mentioned as a technical problem. Key technical characteristics such as: accuracy, linearity, repeatability and the level of possible automation are enabled by electrical or hydraulic signals from the linear position transmitter (8) built into the body of the hydraulic cylinder (3).

The hydrodynamic characteristics and the basic external structure and the method of flow are known from the state of the art, and it is known that such a structure prevents damage to the valve material due to cavitation, given that the cavitation effect is focused on an area where there is no material, somewhere further behind the nut (13) in the center of the pipeline , which simultaneously reduces mechanical vibrations (noise) during operation.

A significant improvement in the hydrodynamic characteristics of the invention is the result of: the minimum required cross-section of the ribs (16), additional guidance of the regulating piston via the piston (4) and connecting rod (5) of the hydraulic cylinder, a strong spring (6) or the use of an external hydro-accumulator that significantly reduces vibrations and other unwanted effects in the regulation phase. The design of the invention enables longer control strokes - determined by the used hydraulic cylinder (3) - which results in an improvement in the control characteristics of the valve.

The safety aspects of the automatic closing are completely solved either by installing a sufficiently strong return spring (6) that acts independently, or by using fluid energy drawn from a pressure fluid source (27), or by a combination of them as discussed earlier in three possible embodiments of the invention.

Noise during operation is reduced precisely by the structural finesse of the cover (7), which separates the flow of fluid and forces it to flow around the ribs (16), which are very narrow in construction and designed in such a way that they do not represent a significant obstacle and do not cause major vortices. The design of the outlet part of the valve (15) contributes to a further reduction in noise compared to other types of valves and shut-off fittings. The outlet part of the valve (15) is also the biggest source of noise due to the intense energy conversion in that place due to the connection of the fluid flows that flow through the ribs (16) and the regulating piston (12) in some intermediate position. The output part (15) can be of different structural designs. The type and shape of the outlet part (15) of the valve (1) mainly depends on the pressure difference and the flow rate - as also shown in the prior art documents.

In the case of return hydraulic shocks that occur, for example, in the closed position of the valve, the forces or pressures are not transmitted to the entire diameter of the regulating piston (12), but act exclusively on the difference in surfaces ΔA:

ΔA=(D12-D22)/(π/4)

where D1 represents the largest outer diameter of the regulating piston (12), and D2 the inner diameter of the outlet part of the valve (15).

When the valve is in one of the possible intermediate positions - the regulating piston (12) is hydrostatically completely relieved, and this feature contributes to the high regulating and mechanical reliability of the valve itself.

Valve application

In the following examples and accompanying drawings, the arrow indicates the direction of fluid flow through the valve body (1), and the double-sided arrow indicates the direction of movement of the regulating piston (12).

Example 1 – PID regulation in a closed loop

Drawing 4 shows the principle diagram of a closed-loop control valve, so that the entire control system together with the valve forms a proportional-integration-derivative (hereinafter referred to as PID) flow and pressure regulator.

The control valve processor (28) receives and executes commands from the remote control station (29), which changes the input parameters as necessary and sends them in the form of commands to the control valve processor (28). The remote control point (29) through the processor (28) controls the set amount of fluid flow and pressure p2. In the case of a decrease in the output pressure of the fluid by a certain value -Δp2 registered by the output pressure probe (26), the valve processor (28) gives an order to the pressure fluid source (27) to increase the opening of the valve, which is expressed by the displacement -Δx, which automatically leads to an increase in the output pressure p2 . At the same time, the flow through the valve also changes, which is registered by the flow meter (24). If a change in flow is recorded within predetermined limits - it is approved, and if it is not, the local processor of the valve (28) performs a correction according to the corresponding program with the aim of maintaining the given output pressure, flow or some other parameter or program combination.

By taking a new position of the regulating piston (12), depending on the technical characteristics of the valve itself, a new regime of flow through the valve is established, where the parameters of such a new regime are monitored via:

- pressure probes (25) for measuring inlet pressure p1,

- pressure probes (26) for measuring output pressure p2,

- of the linear position transmitter (8) about the position of the regulating piston (12), i

- flow meter (24), and

they report to the local valve processor (28) and the remote control site (29).

The movement of the regulating piston (12) in the +Δx direction is achieved either by the action of the spring (6) or by the energy stored in the additional source of pressure fluid for driving the hydraulic cylinder (3) or by a combination of both methods as described earlier. Thus, new conditions were established in the regulation loop and depending on which parameters we manage - complete PID regulation. The local valve processor (28) can also enter other parameters, such as water level in the tank, water temperature and the like, which the valve processor or a computer in the remote control station analyzes and takes certain actions for their maintenance or correction.

One of the examples of the importance of controlling the position of the regulating piston (12) is for the case when the local processor of the valve (28) registers a flow and pressure relationship that is not in accordance with the technical characteristics of the valve for that degree of valve opening or the characteristics of the transmission line of the fluid being controlled. Such behavior will cause a warning and through the corresponding program the situation will be analyzed, corrected or just warned about it, either in the local processor (28) or at the remote control point (29).

Example 2 – use of external compressed air energy

Drawing 5 shows the possibility of operating the control valve with external energy in the form of compressed air. By means of the pneumo-hydraulic pressure amplifier (31), the regulating piston (12) is moved in both directions. The compressed air is controlled by the position of the piston in the C4 chamber, which is mechanically connected (by piston rods) to the C3 chamber of the pneumo-hydraulic amplifier (31), which converts the energy of the compressed air into the energy of the working fluid. The hydraulic distributor (30) serves to change direction and controls the process of opening or closing the control valve (12). Damping non-return valves (22) and (23) are placed in the hydraulic lines towards the chambers C1 and C2 of the hydraulic cylinder (3) in a manner well known in the state of the art. The system designed in this way is two-way, which means that the regulating piston (12) is driven in the direction of opening and closing by a pneumo-hydraulic amplifier (31). Any loss of oil in the hydraulic system is automatically compensated from the oil tank (32). The mentioned system is particularly suitable for use with larger control valves.

Drawing 6 shows the possibility of driving the control valve by means of compressed air and a single-acting pneumo-hydraulic pressure amplifier (31). The difference compared to the two-way system shown in drawing 5 is that in this case the activation is performed by a simpler single-way system with safety closing by means of a valve spring (6) or, in the case of larger valves, by the hydro-accumulator of the chamber C1, which is not shown in drawing 6. This solution provides a simple and reliable way of management, especially suitable for the so-called "on/off" control of multiple valves from one source of compressed air. Such compressed air activation systems are particularly suitable for use in flammable and explosive working environments.

Example 3 – control using a hand pump

Drawing 7 shows a simple and probably the most reliable way of two-way activation and regulation of the position of the piston (12) by means of a hand pump (35) and a hand hydraulic distributor (34) which serves to reverse the direction of the hydraulic flow from the hand pump (35). Drawing 8 shows a simple way of activating and taking the position of the regulating piston (12) in the combination of the hand pump (35) and the spring (6). In both cases, the energy stored in the hydro-accumulator of chamber C1, which is not shown in the drawings, can be additionally used.

This mode can be used with all versions, applications and combinations of the control valve as an additional safety activation method in case of the need for forced manual opening or closing of the valve.

Example 4 - the function of a directly controlled non-return valve in the case of an autonomous drive

Drawing 9 shows the control valve in the function of a non-return valve for the case of autonomous operation, i.e. operation without the participation of external energy, where the valve is placed in the safety closed position with the help of spring energy (6). The regulating piston (12) comes to the open position as a result of the action of the pressure of the fluid p1, which is increased in the chamber C5 by means of the fluid transmitter (39) and the control cylinder (57) in relation to the initially created pressure in the chamber C6 of said control cylinder. In the case of direct activation, the valve opening pressure is adjusted with the spring (55) of the control cylinder (57) in such a way that the spring (6) of the regulating piston (12) is compressed. In the closed position of the valve, the force of the spring (6) must be sufficient to realize the sealing force at the positions of the seals (14).

The speed of opening and closing of the regulating piston (12), i.e. the regulating valve (1) itself, is adjusted using the throttle-non-return valve (23). In the event of a power outage or the pump stops working, the fluid pressure p1 drops and the spring (6) closes the valve. When the pressure of the fluid p1 returns to the working level and in the previously described manner, the valve is opened via the control cylinder (57). Position (37) represents the tap that connects the C6 chamber of the control cylinder (57) via the fluid pressure transmitter (39).

The fluid carrier (39) has the task of separating and transferring the pressure p1 of the fluid flowing through the valve (1) from the control hydraulic oil of the chamber C6 of the control cylinder (57).

Drawing 10 shows the control valve in the function of a non-return valve in the case of autonomous operation, similar to drawing 9, with the difference that the control piston (12) is returned to the safety closed position by the energy of the hydraulic accumulator (33) of chamber C1 through the damping check valve (22). . This method ensures reliable closing of the valve, especially with larger nominal diameters and higher operating pressures of the valve.

Example 5 – the function of a pre-controlled opening check valve

Drawing 11 shows the technical solution of the valve with the function of a pre-controlled non-return valve from the description according to drawing 9 with the difference that the activation of the opening is performed indirectly through the control valve (58) activated by the input pressure p1, where the control valve (58) is the so-called NC type ("normally closed"), i.e. which is normally closed.

With the loss of inlet pressure p1, the valve (1) is closed in the case shown by means of the hydraulic accumulator (33) and the damping check valve of the chamber C1 (22). By increasing the inlet pressure p1 above the set pressure, the control valve (58) becomes flowable and activates through the control cylinder (57) the filling of the chamber C2 of the working cylinder (3), thereby opening the valve (1). The pressure at which the activation takes place, i.e. the opening of the valve (1) is adjusted by the spring (36) of the control valve.

The fluid carrier (39) which is connected between the faucet (37) and the control valve (58) has the task of physically separating and transferring the pressure p1 of the fluid flowing through the valve (1) from the control hydraulic oil of the C6 chamber of the control cylinder (57). The mentioned separation of the fluid protects the contact of the dirty fluid that flows through the valve (1) with a separate control hydraulic system. The described solution with pre-control is suitable for a wide range of operating pressures and large nominal valve diameters.

Drawing 12 shows the solution of the valve with the function from the description according to drawing 9 with the difference that the activation of the opening is performed through a special control valve (59) activated by the output pressure p2.

The control valve (59) is of the NO type ("normally open"), in its normal state under the action of the spring (36) it is in the open position, which ensures the constant presence of some adjusted pressure in the chamber C8 of the control cylinder (57). This design enables the valve (1) according to the invention to be constantly in a state of adjusted openness, ensuring the flow of fluid through the body (1) according to the adjustment of the springs (36) of the control valves (58) and (59), thus maintaining the valve outlet (15) desired pressure p2.

In the case of an increase in the inlet pressure p1 above the predetermined set value, there is an increase in the outlet pressure p2 and an additional opening of the valve is automatically performed via the pilot valve (58) in such a way that it starts by filling the chamber C2 of the working cylinder (3).

Example 6 – forced valve closing procedure

Drawing 13 shows the possibility of the control valve (58) and fluid receiving tank (43) being forced to close the control valve by means of an external excitation of the control valve (58).

The external stimulus for activating the control valve (58), depending on the control design, can be electrical "e" or mechanical, i.e. hydraulic or pneumatic - we denote it with the letter "h".

One of the reasons for the forced closing of the valve (1) can be, for example, a rupture of the pipeline - pressure line (48) or the drain of the upper tank (50) shown in drawing 14. In the event of a rupture, there is a sudden increase in the flow rate, which is measured by one of the known flow measurement method. At the same time, there is a certain drop in fluid outlet pressure. Signals from the fluid flow or pressure meter actuate the control valve (58) which releases and quickly empties the C6 chamber of the control cylinder (57) and thus sharply reduces the pressure in the C2 chamber on the piston rod (5) side. The valve (37) is adjusted so that a sufficient drop in fluid pressure is achieved on it to enable rapid discharge of the fluid from the chamber C6 of the control cylinder (57). Thus, the pressure in chamber C1 becomes higher than C2 and the energy stored in the hydraulic accumulator (33) of chamber C1 causes the valve (1) to close. In this case too, the fluid carrier (39) serves to transmit the pressure p1 and protect the control cylinder (57), while the control valve (58), through the throttle valve (41) and the fluid receiving tank (43) are constantly in contact with the fluid that flows through the valve. When dimensioning the tank for fluid reception, one should take into account the working pressures, the number of activations per unit of time or the possible drainage of the control fluid in a manner that is known in the state of the art.

In drawing 14, position (45) indicates the fluid pump, position (44) the lower fluid tank, and position (49) the upper fluid tank. In the event of a drop in pressure p1, the valve (1) is automatically closed, which here has the role of a non-return valve to protect the pump (45) or to close the pipeline (50) of the upper tank in the event of its rupture. Valve (1) is controlled in one of the previously discussed ways shown in drawings 9, 10, 11, 12 and 13.

Example 7 – valve closing procedure in case of fluid backflow

Drawing 15 shows the directly operated control valve (1) in autonomous mode of operation for the case of a safety outlet in the event of backflow of the fluid flow (indicated by the arrow) as a result of hydraulic shock that causes a sudden increase in pressure p2.

In case of a hydraulic shock, there is a sudden increase in pressure p2 by +Δp2, which is brought to the control cylinder (57) through the faucet (38) and the fluid carrier (39), where it is transformed and there is a sudden filling of the chamber C2 of the working cylinder (3), which opens the valve (1), more precisely retracts the regulating piston (12). The pressure at which the opening of the working cylinder (3) is activated is directly adjusted by the spring (55) of the control cylinder (57). The opening speed of the regulating piston (12) can be adjusted with a damping check valve (23). In order to protect the control cylinder (57) from the flow of dirty fluid, a fluid carrier (39) is installed.

Drawing 16 shows the pre-controlled regulating valve (1) in autonomous mode of operation for the case of a safety outlet in the event of backflow of the fluid flow (indicated by the arrow) as a result of a hydraulic shock that causes a sudden increase in pressure p2. The main difference compared to the solution described in Figure 15 is that the activation of the opening is achieved by pre-control via the control valve (58) of the NC type. In the non-activated state, i.e. when under spring force, the control valve (58) is closed. In the case of a sudden increase in pressure by +Δp2, the flow activates the control cylinder (57) which pushes the hydraulic fluid from the chamber C5 of the control cylinder (57) into the C2 of the working cylinder (3) and thus moves the piston (4) in the direction of opening the valve (1) ).

The pressure at which the control valve (58) starts filling the chamber C6 of the control cylinder (57) is adjusted by means of the spring (36), while the opening speed of the valve (1) can be adjusted by means of the damping check valve (23). The corresponding pressure drop of the control fluid as well as the filling speed of the C6 chamber are adjusted with the tap (38). When the pressure p2 returns to the previously set value, the spring (36) closes the control valve (58), the balance of forces is re-established which allows the force of the valve spring (6) to keep the regulating piston (12) in the closed position. The non-return valve (40) is used to bridge the control valve (58) with the purpose of reducing the resistance of the return flow of hydraulic oil from the chamber C6, i.e. ensuring reliable and hydraulic closing of the valve (1). In this case too, the fluid carrier (39) performs the previously mentioned protective function of separating the basic fluid from the control fluid.

Drawing 17 shows the directly operated regulating valve (1) in autonomous mode of functioning for the case of safety outlet in the event of backflow of the fluid flow (indicated by the arrow) as a result of the hydraulic shock that causes a sudden increase in pressure p2. The difference compared to the solution described in Figure 15 is that the closure of the valve is achieved with a hydro-accumulator (33), which is a more reliable solution for larger nominal valve diameters.

Drawing 18 shows the pre-operated control valve (1) in the same function as in drawing 16 for the case of safety quick discharge in case of backflow or hydraulic shock. The difference is that here an external hydraulic accumulator (33) is used to close the valve, which creates pressure in chamber C1. The solution is suitable for larger nominal diameters and higher valve closing forces precisely because of the mentioned pre-control of the control valve (58). The non-return valve (40) also serves here to bridge the control valve (58) with the purpose of reducing the resistance of the return flow of hydraulic oil from the chamber C6, i.e. ensuring reliable and hydraulic closing of the valve (1).

Drawing 19 shows the pre-controlled regulating valve (1) with the fact that in this case it appears in a double function as: protection against hydraulic shock and to ensure the fluid flow for a certain adjusted state of the relationship between the input return pressure p2 and the output fluid pressure p1 which can represent eg the water level in the lower tank. This case of fluid flow can be used when emptying the upper tank into the lower one. The valve (1) is open until the required pressure p1 or the height of the water column is reached in the lower tank. By means of the spring (36) of the control valve (58) of the NC type, the previously mentioned adjustment of the activation pressure of the control cylinder (57) is performed. The spring of the second pilot valve (59), which is NO-type, adjusts the pressure p1, which must be maintained permanently during the regulation procedure. When the set pressure p1 is reached, the control valve (59) is switched to the closed state, which results in the interruption of the opening of the valve (1), i.e. the movement of the regulating piston (12) in the closing direction. In this way, the ratio of pressures p1 and p2 can always be kept in a constant ratio p2/p1.

Drawing 20 shows the control valve (1) in the function of safety opening and quick discharge of the pipeline in case of a sudden failure in the supply of electricity to the pump drive and similar failures when conditions for backflow or hydraulic shock arise. In this construction, control valves (58) of NO-type and (59) of NC-type are used, they are constantly energized either electrically, hydraulically, pneumatically or mechanically.

In the event of a failure of electricity and pumps, conditions for backflow or hydraulic shock are created. In this case, the actuation of the control valve (58) is automatically interrupted and its spring (36) switches it to the flow position when the C2 chamber is filled through the C6 and C5 chambers, i.e. the valve (1) opens, thus preventing hydraulic shock.

When a permitted state is restored, eg power supply, the control valve (58) is energized and closes the flow to chamber C6. At the same time or in accordance with the control procedure, the process of closing the valve (1) is started, which takes place through the excitation of the second pilot valve (59), which is of the NC type and which flows in the excited state. The process of closing the valve (1) takes place in such a way that the control valve (59) in the excited state empties the chamber C6 of the control cylinder (57) and thus enables the spring (6) of the valve (1) to return the control piston (12) to the closed position.

For this type of functioning of the quick outlet system, even after closing the valve, the condition must be met that the outlet pressure p1, into which, for example, the pipeline is emptied via the valve (1), is lower than the pressure p2. In other words, a greater pressure difference enables faster closing of the valve (1).

The fluid carrier (39) also protects the control cylinder (57) in this case, while the design of the control valves (58) and (59) must take into account the properties of the fluid transported through the valve (1).

As in the previously described cases of autonomous control, the non-return valve (40) is also used here to bridge the pilot valve (59) with the purpose of reducing the resistance of the return flow of hydraulic oil from the chamber C6, i.e. ensuring reliable and hydraulic closing of the valve (1).

In drawing 21, the opening system for rapid discharge of fluid is functionally the same as in the description of drawing 20 and is based on the loss of excitation of the control valve (58). The difference in construction can be seen in the process of reclosing the valve (1), which is carried out by emptying the C6 chamber through the pressure transmitter (39) and the control valve (59) into a special container for receiving the fluid (43). This control method is used with a small difference in inlet and outlet pressure (p2 and p1), which could affect the reliability of reclosing the valve (1). When dimensioning the container for fluid reception (43), the type of fluid, the volume of the chamber C6, the pressure of the fluid and the number of possible closures of the valve (1) per unit of time should be taken into account.

Drawing 22 shows the solution of the autonomous application of the control valve (1) in the function of the so-called "by-pass" outlet for maintaining a constant difference in fluid pressures p1 and p2 of the upper (49) and lower (44) fluid tanks. In the specific case from drawing 22 - maintaining a constant level of the lower and upper tank - the control valve (1) has the function of a "by-pass" valve to the existing shut-off fittings, for example in the latches (47), through which the upper tank (49) is emptied through pipeline (48) in a fast and high-quality way. Position (46) represents the butterfly valve as protection for the pump (45). The emptying of the upper tank (49) and the automatic filling of the lower tank (44) can be adjusted to open the valve (1) at any difference in fluid pressures p1-p2 by the construction solution shown in drawing 19 or in a controllable way described in drawings 20 and 21.

Example 8 – use as a reduction valve

Drawing 23 shows the directly controlled control valve (1) in the autonomous mode of functioning of the standard reduction valve with the task of reducing the inlet pressure p1 and "keeping" the outlet pressure p2 at a constant set value. The spring (55) of the control cylinder (57) adjusts the pressure of the chamber C1 of the hydraulic working cylinder (3) and thus the certain opening of the control valve (1), which results in a correspondingly adjusted output pressure p2. In the case of an increase in the inlet pressure of the fluid p1 by some +Δp1, the transformed hydraulic pressure is transmitted through the fluid transmitter (39) to the chamber C6 of the control cylinder (57), and from it to the chamber C1 of the working cylinder (3), connected to the chamber C5 and the chamber C2 of the working cylinder connected to the chamber C7. Adjusting the output pressure p2 is performed by tightening/unloading the spring (55) of the control cylinder (57), which adjusts the output pressure p2 by moving the control piston (12) in the -Δx /+Δx direction, which leads to an increase/decrease in the pressure p2 and its further maintenance at that set value, i.e. p2=const.

In the case of a drop in the inlet pressure of the fluid p1 in relation to the set value, due to the action of the spring (55) of the control cylinder (57), the hydraulic pressure in the chamber C1 of the hydraulic working cylinder (3) drops, which results in the displacement of the control piston (12) by -Δx, which it is necessary to open the control valve and maintain the set output pressure, i.e. p2=const.

Directly controlled reduction valves in this version are practical for smaller and medium-sized valves, which is mainly limited by the spring (55) of the control cylinder (57).

Drawing 24 shows the pre-operated control valve (1) with the basic mode of operation described according to drawing 23. The difference is that the control of the control cylinder (57) and thus the regulation of the inlet and outlet pressure takes place through a special controllable valve (60) of proportional type. The spring (36) of the valve (60) sets the desired pressure p2 that we want to maintain at the valve outlet. The pre-controlled reduction valve (1) is used for more demanding control tasks, especially for valves with larger nominal diameters and a larger pressure control range.

Drawing 25 shows the control valve in the function of reducing the inlet pressure of the fluid p1 to some outlet pressure p2, but also maintaining their difference at some proportional adjusted value. The difference between inlet p1 and outlet p2 fluid pressure is determined by the degree of valve opening, and is adjusted by the hydraulic control cylinder (57) or more precisely by springs (55) and (56). When there is an increase in the inlet pressure of the fluid p1 by some +Δp1, through the control cylinder (57) there is an increase in the hydraulic pressure in the chamber C2 of the working cylinder (3) and a new equilibrium value of the pressures of the chambers C1 and C2, and the opening of the valve by -Δx which increases the output pressure of the fluid p2 by +Δp2. In this way, the pressure ratio p1/p2=const. is maintained, in accordance with the adjusted characteristics of the springs (55) and (56) of the control cylinder (57), which control the opening or closing of the valve.

Drawing 26 shows a pre-actuated control valve (1) with the basic mode of operation described according to drawing 25. The difference is that the control of the control cylinder (57) is realized by means of the springs (36) of the control valves (60) of the proportional type which are hydraulically activated. Springs (36) set the required pressure p2, which we want to keep constant. The pre-controlled reduction valve (1) is used for more demanding control tasks, especially for valves with larger nominal diameters and a larger pressure control range. Fluid carriers (39), as in other schemes, separate the fluid that is transported by the valve (1) and the hydraulic oil that is used in the regulation and adjustment system by the valve. In this way, quality, reliability and long-term use are obtained while reducing maintenance costs.

Drawing 27 shows the multiple usability of the control valve (1) in the autonomous operation mode for the classic adjustment of the pressures of different consumers. Thus, the valve can be used as a reduction valve at the entrance of the pipeline branches of private (51), industrial (52) and combined (53) consumers, and at the end of these lines also as valves to prevent hydraulic shock.

Consumers on lines (51), (52) and (53) are supplied from one pumping plant consisting of a pump (45) for fluid, a valve (1) in the function of a pump protection check valve (connected in series with pump (45)), and the valve (1) connected in parallel to the pump (45) as protection of the system against hydraulic shock and the tank (44), as shown, for example, in drawing 15.

Example 9 – Calculation of forces for open, closed and intermediate valve positions

Drawing 28 represents the representation of forces and pressures on the open valve (1) as well as for some intermediate position of the regulating piston (12) of the valve (1). In the previously discussed examples 1-8 when adjusting the working area of the valve, i.e. the relationship between the forces of the valve spring (6), hydraulic accumulator (33) or in the described direct control of the spring forces (55) of the control cylinder (57) or in the pre-control of the transformed fluid forces, when opening or closing the valve - it should be taken into account that the axial force Fx exerted by the fluid on the regulating piston (12), see drawing 28, is not a constant value during the regulating stroke.

The axial force changes in direction and amount according to the formula:

Fx= CFX∙(DN²π/4)∙(p1-p2)

where the parameter CFX represents the coefficient of axial force and is calculated by hydrodynamic equations, and DN is the nominal diameter of the valve.

After numerical hydrodynamic analyzes of the axial force coefficient, it was established that the axial force on the regulating piston (12) suddenly changes direction immediately before the valve closes. This means that in a larger working area, the fluid "pulls" the regulating piston (12) in the direction of flow, while immediately before closing it "pushes" it backwards. At the same time, the maximum value of the axial force is only 10% of the product of the pressure difference acting on the valve and the front surface of the regulating piston (12).

This fact is extremely important when applying the valve in the autonomous mode of functioning of the valve, i.e. without the participation of external energy. In doing so, the balance condition of the forces acting on the regulating piston in the intermediate position must be satisfied, which reads:

Fx = Fh1 - Fh2 + Fs

that is, according to drawing 29 in the closed position of the regulating piston:

Fx = Fp2 - Fp1 + Fh1 - Fh2 + Fs

where the symbols used have the following meaning:

Fh1 - force of hydraulic pressure in the chamber C1 of the cylinder (3)

Fh2 - hydraulic pressure force in the C2 cylinder chamber (3)

Fp1 - force due to external pressure p1

Fp2 - resultant effect of pressure p2 on both sides of the regulating piston (12)

Fs - the force of the spring (6) or hydro-accumulator (33)

D1 and D2 represent the essential dimensions of the regulating piston (12), in the part that is inserted into the central part of the body (2) - D1 and the sealing part that enters the outlet part of the valve (15) - D2. Numerical analyzes showed the exceptional efficiency of the valve (1) according to the subject invention for use in regulation examples 1-8.

It should be said that in all aspects of the application described in examples 2-8, the linear position transmitter can be either of the electrical or mechanical type, but according to the need for monitoring the progress of the regulation process that is carried out by the valve that is the subject of this invention.

In examples 2-8, it is clear to an expert in the field that the fluid pressure transmitter (39) does not need to be installed in systems that transport the so-called "pure fluids"; oil, gas, oil, drinking water, etc. Therefore, instead of said fluid pressure transmitter (39) - fluid pressure can be used directly for regulation in the autonomous drive, which is transmitted through the basic line through which that fluid flows and whose flow is regulated by said valve . Such "pure" working fluid transported through the pipeline enters the inlet chambers of the control cylinder (57) directly or through one or more control valves (58), (59), (60); while the hydraulic circuit of the output chambers of the control cylinder (57) and the hydraulic cylinder (3) is completely separated from the working fluid.

Industrial applicability

The industrial applicability of the invention is unquestionable and obvious as a control and shut-off valve for flow and pressure regulation in the water, air, gas and oil transport system, especially when it comes to large transports per unit of time. The practical purpose is to use in all places where reliable, linear and repeatable fluid flow control is required.

Call signs

1 – valve (valve body)

2 – the central part of the body

3 – hydraulic cylinder

4 – cylinder piston

5 – connecting rod

6 – valve spring

7 – linear encoder cover

8 – linear position encoder

9 – longitudinal guides (of the regulating piston)

10 – hydraulic cylinder head

11 – piston seal between (12) and (2)

12 – regulating piston

13 – nut that tightens (12) for (5)

14 – seal between (15) and (12) in the closed state of the valve

15 – outlet part of the valve body

16 – ribs

17 – hydraulic channels

18 – channels for guides (linear position sensor)

19 – measured distance

20 – magnetostrictive waveguide (probe)

21 – permanent magnet of the electric linear position transmitter

22 - damping check valve of chamber C1

23 - damping check valve of chamber C2

24 - flow meter

25 - pressure probe

26 - pressure probe

27 - source of pressure fluid

28 - control valve processor

29 - remote management site

30 - hydraulic distributor for direction reversal

31 – single or double pneumo-hydraulic pressure amplifier

32 – oil tank

33 – hydraulic accumulator of chamber C1

34 - manual hydraulic distributor

35 - manual pump

36 - control valve spring

37 – faucet

38 - faucet

39 – fluid pressure transmitter

40 - non-return valve

41 - pilot valve damping valve (58)

43 - fluid receiving tank

44 - lower fluid tank

45 - pump

46 – butterfly valve

47 – latch or some other type of locking device

48 - pressure line

49 - upper fluid reservoir

50 – upper tank drain

51 - private consumer pipeline branch

52 - branch of pipeline of industrial consumers

53 - branch of the pipeline of combined consumers

55 - spring for adjusting the pressure of the chamber C6

56 - spring for adjusting chamber pressure C8

57 - control cylinder

58 – NC type control valve

59 – NO type control valve

60 – proportional control valve

Claims (19)

1. The hydraulic axial piston control valve consists of: - the valve body (1) and the central part (2) around which the fluid flows when the valve is open, and where the central part (2) is connected with one or more ribs (16) to the valve body (1), where said ribs ( 16) equipped with hydraulic channels (17) and additional channels for guides (18); - of the central part (2) with the hydraulic cylinder (3) in communication with said hydraulic channels (17), inside which is the body of the hydraulic piston (4) and the connecting rod (5) to which the regulating piston (12) is attached; and - one or more seals (11) that permanently seal between the central part (2) and the regulating piston (12), and one or more seals (14) between the regulating piston (12) and the outlet part of the valve body (15) that seal only in closed valve position; indicated by: - that the linear encoder of the position (8) of the regulating piston (12) is located centrally inside the hydraulic cylinder (3) of the central part (2) of the valve; - that the movement of the regulating piston (12) is defined by the longitudinal guides of the piston (9) located on the inside of the central part of the body (2); and - that the regulating piston (12) is equipped with slots and holes for hydrostatic relief of the regulating piston (12). 2. Hydraulic axial piston control valve according to claim 1, characterized in that: - the regulating piston (12) has a spring (6) located in its head, which on one side rests against the outer side of the hydraulic cylinder (3), and on the other against the inner bottom of the regulating piston (12); and - where the built-in spring (6) has enough elastic energy to safely set the regulating piston (12) in the position to completely close the flow of fluid through the valve in the event of a loss of pressure in the hydraulic channels (17). 3. Hydraulic axial piston regulating valve according to claim 1, characterized in that only hydraulic pressure from an external source of pressure fluid (27) is used to safely return the regulating piston (12) to the closed position. 4. Hydraulic axial piston regulating valve according to claim 2, characterized in that the hydraulic pressure of the external source (27) of the pressure fluid is additionally used to safely return the regulating piston (12) to the closed position. 5. Hydraulic axial piston control valve according to any of the preceding requirements, characterized in that: - is a position sensor (8) of an electrical type that converts the distance (19) into a measurable linear electrical quantity which is carried by wires through one or more holes (18) made in the ribs (16) and taken out from the central part (2) of the valve body (1 ), i - where the position transmitter (8) is closed by the cover (7) of the front part (2) of the valve. 6. Hydraulic axial piston control valve according to claim 5, characterized in that the data collected from the position transmitter (8) about the position of the control piston (12) are additionally numerically processed in the control valve processor (28). 7. The use of a hydraulic axial piston control valve defined in claims 5-6, characterized by the fact that it is used in PID regulation in a closed loop where the processor of the control valve (28) - autonomously or according to the orders of the remote control site (29) - executes the protocol according to the collected data from pressure probes (25) and (26), flow meter (24) and linear position transmitter (8), and where spring energy (6) is used to close the valve, or energy stored in an external source of fluid pressure (27) or combined . 8. The use of a hydraulic axial piston control valve defined by any of the preceding claims 1-6, characterized by the fact that the movement of the control piston (12) in both directions is performed by compressed air and with the help of a pneumo-hydraulic pressure amplifier (31). 9. The use of a hydraulic axial piston control valve defined by any of the preceding claims 1-6, characterized in that the position of the control piston (12) is controlled by a hand pump (35). 10. The use of a hydraulic axial piston control valve defined by any of the preceding claims 1-6, characterized in that it is used as a non-return valve in the case of an autonomous drive, where the energy for the drive is taken in the form of a working fluid by a tap (37) and via a pressure transmitter fluid (39) leads to the control cylinder (57) - directly or through the control valves - and the control cylinder (57) controls the working cylinder (3) through the damped non-return valve (23). 11. Use of a hydraulic axial piston control valve according to claim 10, characterized in that the control cylinder (57) is pre-controlled with one or two control valves (58) and (59) connected via the fluid pressure transmitter (39) to the fluid baseline. 12. The use of a hydraulic axial piston control valve according to claim 11, characterized in that the control cylinder (57) is controlled by an additional excitation on the control valve (58) connected to the fluid receiving tank (43). 13. The use of a hydraulic axial piston control valve defined by any of the preceding claims 10-12, characterized in that it is used in a safety connection for forced closure in the event of a rupture of the pressure line (48). 14. The use of a hydraulic axial piston control valve defined by any of the preceding claims 1-6, characterized in that it is used in the case of fluid backflow or hydraulic shock, where the drive energy is taken in the form of a working fluid by a tap (38) and via a transmission of fluid pressure (39) leads to the control cylinder (57) - directly or through the control valves - and the control cylinder (57) controls the working cylinder (3) through the damped non-return valve (23). 15. Use of a hydraulic axial piston control valve according to claim 14, characterized in that the control cylinder (57) is pre-controlled with one or two control valves (58) and (59) connected via the fluid pressure transmitter (39) to the fluid baseline. 16. The use of a hydraulic axial piston control valve according to claim 15, characterized in that the control cylinder (57) is controlled by an additional excitation on the control valve (58) connected to the fluid receiving tank (43). 17. The use of a hydraulic axial piston control valve defined by any of the preceding claims 1-6, characterized in that it is used in the function of reducing the fluid inlet pressure p1 to some outlet pressure p2 and maintaining their difference at some proportional value, where the drive energy is taken in the form of a working fluid from one faucet (37) and or from both faucets (37) and (38), and where the said pressures p1 and p2 are led to the control cylinder (57) via the corresponding fluid pressure transmitters (39) - directly or through the control valves – and the control cylinder (57) through the damped non-return valve (22) and (23) controls the operation of the working cylinder (3) which drives the control piston (12). 18. The use of a hydraulic axial piston control valve according to claim 17, characterized in that the control cylinder (57) is pre-controlled with one or two proportional control valves (60) connected via their fluid pressure transmitters (39) to the basic fluid line by taps (37) and (38). 19. The use of a hydraulic axial piston control valve defined by any of the previous claims 10-18, characterized in that fluid pressure transmitters (39) are released in said hydraulic lines and that the working fluid transported through the pipeline enters the inlet chambers of the control cylinder (57 ) directly or through one or more control valves (58), (59), (60); while the hydraulic circuit of the output chambers of the control cylinder (57) and the hydraulic cylinder (3) is completely separated from the working fluid.