BR202016014153U2 - hydropneumatic tank to cushion water hammer or to increase pressure in a fluid network such as drinking water - Google Patents

Abstract

hydropneumatic tank to cushion water hammer or to increase pressure in a fluid network such as drinking water. a hydropneumatic tank for cushioning water hammer or for increasing pressure in a fluid network such as drinking water or wherever there is incompressible fluid to be installed in a pipeline (12) of a pumping station that experiences pressure variations, the hydropneumatic (14) being formed by a receptacle (15) which has a lower lid (16) and an upper lid (17), where from the lower lid (16) emerges a connecting pipe (13) to connect with the pipe (12). centrally located within receptacle (15) is a guide tube (23) having a first end joined to a frame (26) firmly adhered to the upper inner portion of receptacle (15) and a second end having a base (24): said guide tube (23) is a guide rail that guides a sliding plate (25) that moves between an upper and lower position, forming a liquid fluid chamber (27) and a gas fluid chamber (28); and said hydropneumatic (14) has on the top cover (17) a valve (29) which is enclosed in a compartment formed by a cylindrical receptacle (18) which has an access cover (19), where between the access cover (19) ) and the cylindrical receptacle (18) is located a third rubber seal or o-ring (33).

Description

HYDROPNEUMATIC TANK TO DAMAGE THE RIPPER OR TO INCREASE PRESSURE IN A FLUID NETWORK LIKE DRINKING WATER.

Field of the Invention The present invention relates to a (hydropneumatic) pressure vessel that is used to dampen the water hammer or to increase the pressure in a drinking water network. More specifically, the present invention relates to a hydropneumatic tank having a sliding plate or disc on a vertical central axis which separates the liquid fluid chamber from the pressurized air containing chamber.

Prior Art Comments [002] Pumps at pumping stations generate strong drops and pressure increases due to normal shutdown or power outage, as well as pump start-up or even flow variations during operation. Stopping pumps produces a rapid drop in pressure along the entire water line and then violently increases pressure at the pump and pumping line. This endangers the integrity of the pipe, even if it is steel, if a water hammer control device has not been designed and installed.

[003] This phenomenon has been addressed in different areas of study and various elements have been constructed for its control or damping of pressure variations.

Currently there are several protection devices for this phenomenon according to the layout of the hydraulic pumping system, such as: hydropneumatic tanks (or pressure vessels), balance chimneys, suction cups, one way tanks, blowout valves. water hammer or pressure relief valves.

[005] One of the most suitable protective elements used by engineers or technicians to control water hammer in pumping stations is the hydropneumatic tanks, which are usually located near the pump house. These tanks can be of two different types: a) With elastomeric bladder that isolates air from water in which both are under pressure. b) With air in direct contact with water and a compressor that injects air due to the loss of this fluid by being in direct contact with water under pressure.

[006] Figure 1 shows a typical hydropneumatic tank with internal elastomeric bladder. This tank (1) connects to the piping (2) of the pumping station that is the one that suffers the pressure variations by water hammer. A valve (3) allows the tank to be isolated from the pipeline if maintenance or even repair is required.

[007] The tank (1) has an elastomeric bladder or bladder (4) inside which contains water from the hydraulic system as it is connected to the tubing (2). Between the pocket (4) and the tank (1), pressurized air (5) is injected from the outside through an air valve (6). In this way, the pouch (4) separates air from water, which is why air does not dissipate through water. Pressure variations due to water hammer are dampened by the expansion and contraction of the air (5), which causes the pouch (4) to inject and admit water through and from the hydraulic system.

[008] This type of hydropneumatic tank is not suitable for use in sewage pumping because sewage may contain different elements such as nails, glass, needles, etc. that can break the bag (4), and thus the tank would completely lose its function. Still in the case of clean water, such as drinking water, this type of tank can lose its function if the bag (4) ruptures or the compressed air (5) escapes through the valve (6). This requires continuous monitoring of these elements and repair or replacement of the pouch (4) if necessary.

[009] Figure 2 shows the other known type of hydropneumatic that engineers design as a protective element against the effects of water hammer. This version is sometimes called as "air bell".

[0010] This device has no inner membrane, allowing direct contact of pressurized air (5) with water (7). Since air in direct contact with water, both being under pressure, is gradually diluting, it is necessary to install a compressor (8) which replenishes the air through a connection to the interior of the tank, but is also required. the internal installation of bars will detect the water level that emits an electrical signal to start the compressor. Other bars indicate that the compressor will stop injecting air. In addition, there are two more bars that should warn that the compressor has not started or has not stopped injecting when it should do so. All this requires an electrical system to command all these operations.

The compressor tank can be used for both clean water and sewage; however, this device may only be installed inside the pump room enclosure as it requires electrical power to operate the electrical trays or PLC.

In addition to the types of tanks already described, there have been attempts to control water hammer by other devices, such as ES 2019742, entitled "Removable Diaphragm Multiple Check Valve" discloses and consists of a check valve. multiple-diaphragm manifold of the type consisting of two semibodies in whose coupling zone presents a diaphragm with a series of valves which, immediately ceased to pressure, return to their positions aided by springs and the water weight itself, damping almost the battering ram and comprising in the joint area of the two semibodies a box-like receptacle with guides, capable of receiving the diaphragm mounted on a withdrawable support body having means for fixing, immobilizing and receiving the support body .

In addition, document ES 2138490, entitled "Pipe and Valve Coupling Coupling System", discloses and consists of a coupling system for pipe and valve coupling with special application in liquid fluid conduits. It includes two juxtaposed independent parts, functionally differentiated for their specific purposes, which are, respectively, the joint reception and the pipe retention to support the impacts of the water hammer.

This document EP 266594, entitled "ball griffon", discloses and consists of a ball spout (or tap) that has a device that automatically locks its operating axis in its rotating position between closed position and open position when operating movement is produced too quickly. This locking device responds to the respective rotational position of an annular inertia body that rests swivelly on the spout support with which the spring-driven rotational movement of said body is released by the movement of the operating shaft if see inhibited by the inertia of its mass; By driving the operating shaft at an appropriate slow speed, the locking device is disabled. But if the drive is unacceptably fast and can lead to high pressures, the operating shaft is blocked by the device it has for this purpose.

EP 239451, entitled "Special Anti-Return Valve Assembly for Pressurized Water Reactor Application" discloses and consists of an assembly which is intended to shut off a fluid circuit without generating water hammer, and which comprises a body At each end, the tubular tube is connected to each pipe by an open and closed movable plug.

According to this invention, the plug is slidably axially mounted and encloses a cylinder that assists a fixed piston to constitute a high-efficiency brake device.

DE 102012005447 discloses and consists of a pressure storage system having a hollow cylindrical casing delimiting two spaces of variable volume and which are separated from each other by a movably spaced apart member disposed within. housing, generating enclosed and sealed spaces against each other.

The housing is formed of steel and comprises a hollow lower cylindrical shaped tube which is partially contained by an outer tube formed of profiled steel plate. The separating element is comprised of a piston. The inner and outer tubes are integrally connected between them.

GB 581268 discloses and consists of a piston for a hydraulic accumulator, where the tank contains two chambers sealed by metal rings divided with an internal bevel and sealed by a rubber ring supported by a ring. Thin enlarged and tight against the interior wall of the tank. The gas pressure above the piston has access to the groove through small holes.

GB 682825 discloses and consists of a free piston tank for separating a liquid from a gas within a hydraulic accumulator. This accumulator has two piston discs rigidly connected to each other and with a space between the discs, each having a seal against the inner wall of the cylinder where the liquid side seal member is adapted to allow liquid to penetrate into the space. however, both sealing parts are adapted to prevent fluid leakage. The sealing parts expand by washers pressed axially by a spring.

Document JPS5722401 discloses and consists of a system for enabling and immediately detecting the occurrence of gas leaks, activating an alarm when the gas pressure of a pressure accumulator is lower than the fluid pressure. The interior of the pressure accumulator body is divided by a piston such that the gas chambers are defined over the piston and a fluid chamber is defined below the piston.

US 2780504 discloses and consists of an accumulator piston tank. The piston is floating which moves freely within a cylinder by a pressure differential between opposite sides of the two chambers separated by the piston, containing air or any gas and the other containing fluid. The purpose of this pressure accumulator is to provide a piston for the anterior accumulator wherein a sealing means is disposed midway between the ends of the piston and is constructed such that the sealing member is confined to a limitedly limited piston groove. The groove walls have minimal separation with the cylinder wall. The floating piston for the accumulator cylinder comprises a generally cylindrical body which has two spaced walls forming an intermediate annular groove at the ends thereof, said walls having a diameter for tightly fitting within the cylinder a said tightness seal in said and in contact with the cylinder seal, said body also has an annular groove in its outer surface adjacent to each end thereof and defined between two outwardly extending spaced walls. The plastic ring mids in each of the two mentioned grooves contact the base of each groove and the cylinder to keep the piston centered within the cylinder and to be rigid and low coefficient of friction to allow free movement of the piston. piston inside the cylinder.

SUMMARY OF THE INVENTION The present invention relates to a hydropneumatic tank for cushioning water hammer or well for increasing pressure in a drinking water network. More specifically, the invention relates to a hydropneumatic tank having in its center a vertical guide tube in which a rigid plate is slid whose outer edge, in all its perimeter, is in contact with the inner wall of the tank such that separates two chambers one upper containing pressure air and one lower containing liquid fluid each time the plate slides vertically through the central tube. Thus, when the pressure increases in the pumping line and therefore inside the tank, the plate rises, thus decreasing the volume of the air chamber and its pressure, damping the pressure increase. On the other hand, when the pressure in the pumping line drops, and therefore inside the tank, the air in the upper chamber expands causing this to enter water into the hydraulic system and consequently decreasing the pressure drop in the pumping line.

The conformation of this hydropneumatic tank of the present invention allows the construction of a much more economical and above all much easier to operate hydropneumatic tank without external apparatus than those disclosed in the prior art invention.

BRIEF DESCRIPTION OF THE DRAWINGS The drawings which are included are intended to provide a better understanding of the invention: they are incorporated and form part of this description, illustrate part of the prior art and an embodiment of the invention, and which together with the description serve to explain the principles of the invention.

Figure 1 shows a half-sectional view of a known typical hydropneumatic tank containing a prior art internal elastomeric pouch.

Figure 2 shows a half-sectional view of another type of a hydropneumatic tank known in the prior art.

Figure 3 shows a top perspective view of the hydropneumatic tank of the present invention.

Figure 4 shows a bottom perspective view of the hydropneumatic tank of the present invention.

Figure 5 shows a half-sectional view of the hydropneumatic tank of the present invention.

Figure 6 shows a perspective view of the guide tube located within the hydropneumatic tank of the present invention.

Figure 7 shows a bottom perspective view of the guide tube located within the hydropneumatic tank of the present invention.

Figure 8 shows a top perspective view of the guide tube and rigid plate located within the hydropneumatic tank of the present invention.

Figure 9 shows a bottom perspective view of the guide tube and rigid plate located within the hydropneumatic tank of the present invention.

Figure 10 shows a top perspective view of the guide tube and a second embodiment of the rigid plate located within the hydropneumatic tank of the present invention.

[0035] Figure 11 shows a front elevational view of the guide tube and the outer rubber seal rigid plate, both located inside the hydropneumatic tank of the present invention.

Figure 12 shows a top perspective view of the guide tube and the outer rubber seal rigid plate, both located inside the hydropneumatic tank of the present invention.

Figure 13 shows a front elevational view of a third embodiment of the rigid plate and guide tube, both located within the hydropneumatic tank of the present invention.

Figures 14 and 15 show a bottom perspective view of a third embodiment of the rigid plate and guide tube, both located within the hydropneumatic tank of the present invention.

Figure 15 shows a bottom perspective view of a third embodiment of the rigid plate and guide tube, both located within the hydropneumatic tank of the present invention.

Figure 16 shows a top perspective view of a fourth embodiment of the rigid plate and guide tube, both located within the hydropneumatic tank of the present invention.

Figure 17 shows a bottom perspective view of a fourth embodiment of the rigid plate and guide tube, both located within the hydropneumatic tank of the present invention.

Figure 18 shows a front view of a fourth embodiment of the rigid plate and guide tube, both located within the hydropneumatic tank of the present invention.

[0043] Figure 19 shows an enlarged view of the hydropneumatic tank air release valve of the present invention.

[0044] Figure 20 shows an enlarged view of the sliding plate installed in the hydropneumatic tank guide tube of the present invention.

Description of the Invention The present invention relates to a hydropneumatic tank for cushioning water hammer by pressure drop or for increasing pressure in a fluid network such as drinking water or any system where there is a incompressible fluid, including copper leaching systems, ore pulp or any liquid or semi-liquid fluid. More specifically, this invention relates to a hydropneumatic tank (14) installed in a pipe (12) of a pumping station which is subjected to pressure variations due to flow variation.

As illustrated in figures 3 to 5 said hydropneumatic tank (14) is formed by a receptacle (15) which has a lower lid (16) and an upper lid (17) and which from the lower lid (16) a connecting pipe (13) emerges to connect to the pumping station pipe (12).

In the center of the interior of the receptacle (15) is a guide tube (23) which at a first end hangs from a structure (26) firmly adhered to the upper inner portion of the receptacle (15). The second end of the guide tube (23) ends at a base (24). Between frame (26) and base (24), guide tube (23) is formed by a guide rail for sliding plate (25) between an upper and lower position. The sliding plate (25) is for forming a liquid fluid chamber (27) such as water and a gaseous fluid chamber (28) such as air or nitrogen.

As shown in Figures 5, 8 and 9, the outer edge of the sliding plate may be at the top by touching the base (24) with the inner surface of the receptacle (15), as the fluid from the liquid chamber (27) ) is incompressible and acts by itself as a seal.

Depending on some conditions such as tank size and air loss, for all two chambers (27, 28) to be independently and without fluid exchange, the sliding plate may have a recess in its outer contour (not shown in the figure) where a first rubber seal or O-ring (34) is placed that presses on the inner surface of the receptacle (15). In order for the sliding plate (25) to move over the guide tube (23), it has a central cavity (30) on whose inner edge it has a recess (not shown in the figure) to receive a second rubber or O-seal. ring (35) which presses on the outer surface of the guide tube (23). Thus, when the pumping station piping (12) causes a sudden increase in pressure, the liquid fluid in the liquid fluid chamber (27) increases the level and thereby moves the sliding plate (25) compressing the gaseous fluid in the gaseous fluid chamber (28) The sliding plate (25) generally consists of a round disk, however, in a second embodiment, this plate may be a flat cylinder as shown in Figure 10. 15 shows that the sliding plate (25) may have a third embodiment, which consists of a concave plate (31). To seal between this concave plate (31) and the inner wall of the receptacle (15), a rubber blade (32) is located which slides together with said plate.

In a fourth embodiment, as shown in Figures 16 to 18, the sliding plate is formed by an upper rigid portion (25a) and a lower rigid portion (25b), between which a rubber blade slides. (35) larger in diameter than said portions (25a, 25b) whose edge bends downwards as the plate rises, or well, the edge bends upwards as the plate descends, thereby generating a seal between the chambers (27,28 ).

In some cases it is necessary to release or inject gaseous fluid into the hydropneumatic tank (14). For such action, said tank has on the top cover (17) a valve (29) which is enclosed in a compartment formed by a cylindrical receptacle (18) which has a lit cap (10) allowing to leave the valve (29) ) isolated to prevent third party interventions. Likewise, said housing is sealed to the outside and thus prevents leakage by valve (29) which could generate pressure problems in the hydropneumatic tank (14). For this, between the light cap (19) and the cylindrical receptacle (18) there is a third sealing seal u O-ring (33) [0054] To have a control of the chambers (27,28) the receptacle (15) has a lower tap (22) connected to the fluid fluid chamber (27) and an upper tap (21) connected to the gas fluid chamber (28). In such a way that between said leads (21,22) is located a transparent level control tube (20), which inside has a floating ball (not shown) which is collinear with the sliding plate 925), to inform the position of this level and thus to know the capabilities of the two chambers (27,28).

Claims (9)

1- Hydropneumatic tank to dampen water hammer or to increase pressure in a fluid network such as drinking water, or wherever there is an incompressible fluid, to be installed in a piping (12) of a pumping station that undergoes variations of said hydropneumatic tank (14) formed by a receptacle (15) which has a lower lid (16) and an upper lid (17) and where from the lower lid 916) a connection pipe (13) is formed to CONNECTING TO PIPE (12), FEATURED BY: - Centered within the receptacle (15) is a guide tube (23) which has a first end joined to a frame (26) firmly adhered to the upper inner portion of the receptacle (15) and a second end having a base (24); - Such guide tube (23) is formed by a rail that guides the sliding plate (25) which moves between an upper and lower position, thus generating a liquid fluid chamber (27) and a gas fluid chamber ( 28); and said hydropneumatic tank (14) has a valve (29) over the top cover (17) which is enclosed in a compartment formed by a cylindrical receptacle (18) having an access cover (19), and between the cover of (19) and the receptacle (18) are a rubber seal or O-ring (33). Hydropneumatic tank according to claim 1, characterized in that the fluid is water. Hydropneumatic tank according to claim 1, characterized in that the gaseous fluid is air. Hydropneumatic tank according to any one of Claims 1 to 3, characterized in that the sliding plate (25) is in the form of a round disk. Hydropneumatic tank according to any one of claims 1 to 3, characterized in that the sliding plate (25) is in the form of a flat disc. Hydropneumatic tank according to any one of claims 1 to 5, characterized in that the sliding plate (25) in its outer contour has a recess resting a first rubber seal or O-ring (34) which presses on the inner surface of the slider. receptacle (15); said sliding plate (25) further has a central cavity (30) in which the inner surface has a recess for admitting a second rubber or O-ring seal which presses on the outer surface of the guide tube (23) Hydropneumatic tank according to any one of claims 1 to 6, characterized in that said sliding plate (25) has the shape of a concave plate (31) joined to a rubber blade (32) which slides together with the plate. concave (31) Hydropneumatic tank according to any one of the preceding claims, characterized in that the sliding plate is formed by an upper rigid portion (25a) and a lower portion (25b), between which a larger rubber blade (35) slides. diameter than the portions (25a, 25b). A hydropneumatic tank according to any one of the preceding claims, characterized in that said receptacle (15) has a lower branch (22) connected to the liquid fluid chamber (27) and an upper branch (21) connected to the gaseous fluid chamber (27). 28), between which is located a translucent level tube (20) which inside has a small floating ball.