NON-RETURN VALVE WITH A BALL-SHAPED VALVE BODY

Abstract: The valve according to this invention has the casing through-channel (2), which is elbow-shaped or bend-shaped, and the straight line passing through the ball valve body (1) centre, when the ball is in fully open position, passes the through-channel (2) at both its ends. The method according to this invention consists in that after each single flow of liquid through the valve, from inlet to outlet, the alternative liquid flow is directed from the delivery side of an alternative pumping installation to the outlet or to the second (alternative) inlet of the valve through-channel (2), and the outflow takes place from the elbow-shaped (bend-shaped) valve part.

Description: Non-return valve with a ball-shaped valve body The invention relates to a non-return valve with a spherical (ball-shaped, ball) valve body and to a method of the valve flushing, especially in waste water pumping station installations. The Polish patent description no. PL 174 939 presents such non-return valve with a ball-shaped valve body, and a casing equipped with a through-channel (conduit) having an outlet and an inlet terminated with an annular (ring-shaped, ring) valve seat, whereupon the ball valve body is settled in closed position, and additionally equipped with a deflected channel of a diameter larger than the ball valve body diameter, where space is provided for the ball valve body to be set in its open position and where at the inlet, where the deflected channel is interconnected with the through-channel, the valve casing has extended flow cross-section. In this solution inside the valve casing, in front of a corner of the through-channel interconnection with the deflected channel, a double-sided axis- symmetric depression is located, made as external bulge of the valve casing wall and being symmetrical against the valve symmetry axis. Operational examinations of such the valve solution proved, that both the liquid flow energy loss and the valve vibrations were considerably reduced in comparison with known valves of similar kind. Valve vibrations however were not eliminated, especially at high liquid flow, but only reduced. The valve vibrations indicate disturbed flow of the liquid, which causes additional energy losses during the liquid flow through the valve. There are also known non-return valves with ball valve bodies, in which vibrations are eliminated in practise. US patent description no. AP US 2 192 541 presents a non- retnrn valve, which has a deflected through-channel with side openings, concealed at its end by an external bulge, made in the valve casing at the through-channel region, where the ball valve body is set in its fully opened position. In such a way the valve vibration were reduced, but at a great energy expense of the liquid flow through the valve. Due to its design the valve cannot be used for liquids with large dimension solid particles, which are of frequent occurrence in waste water. British patent application no. 2 222 230 presents solutions of non-return valves having a blind flange located at the end of a deflected channel provided with an opening, which is connected by means of a differential pipe to the valve outlet. In one version the valve is equipped with a supporting seat located at the end of the deflected channel, being dedicated for the valve body to be settled in fully open position and having substantially greater diameter than the differential pipe diameter. Small pressure difference, existing between pressure in the deflected channel and pressure in the differential pipe, is assisted by the large acting area of the ball valve body being exposed to reduced pressure in the differential pipe. In such a way the force is increased, which presses the valve body against the seat, what assures greater stability of the ball valve body in its fully open position. The valve however is not useful for liquids with solid particles, which can be frequently found in waste water. U.S. patent description no. 4 4 293 936 discloses a non return valve with a ball valve body, which working principle is similar to the two designs presented above. The valve deflected channel is equipped at its end with a ring-shaped channel, through which a part of the liquid stream flows from the direction of the through-channel's narrowed inlet through the deflective channel, where flowing around the ball valve body in fully opened position, presses it against a grove made in the valve casing and then flows into the through-channel extended outlet. The valve working principle is based upon intentional losses of the liquid flow energy caused by substantially narrowed flow cross-section at the valve inlet in comparison to the outlet flow cross-section. Basic disadvantage of such a solution is a possibility that the ball valve body being continuously washed by the liquid in fully open position can be blocked in this position by solid particles contained in the liquid. It is observed during the operation of a waste water pumping stations that the non-return valve casing internal surfaces are becoming covered with a growth of sediment (sludge deposits) produced by waste water, especially in places where the liquid velocity is low. It causes the valve be not completely opened during its operation and involves out-of-control pressure growth and therefore both the increased energy consumption and the pump wear. Equally critical places in a pump installation pressure pipeline, where the sediment is likely to deposit, are all sorts of bends and elbows, which for the sake of periodical cleaning are sometimes equipped with inspection openings and/or replaceable elbow-shaped covers, especially in the hydraulic transport systems for abrasive media. Non-return valves with ball valve body are frequently mounted near an elbow-shaped duckfoot at the pressure side of the pump installation equipped with a submersible centrifugal pump and necessary fittings. For low flow cross-sections, when two pumps equipped with grinders are used, the solution is employed with two non-return valves being integrated with the connecting face and having common outlet. Due to reduced accessibility to such valves troubles frequently appear during operation. There is a variant of such a solution in a form of non-return valve performing a role of circuit switching device for two pumps, which is equipped with one ball valve body and with two inlets terminated with ring-shaped seats. The valve operation is controlled by alternative switching the pumps, which are connected by delivery flanges to the valve two inlets, while one of the pump is switched on the ball valve body is settled in the opposite inlet and performing as a diaphragm with an opening. Disadvantage of such a solution, presented in European patent application no. EP 0 797 006, consists in the fact that the ball valve body in practise moves in the same channel, as the through-channel common for two delivery branches in a form of the letter "V". Complicated path of the ball valve body movement can cause the body blocking in the through-channel as the solid particles present in the through-channel can effectively block the ball valve body. Because the V-shaped through-channel is almost horizontal the sedimentation process of solid particles from waste water is facilitated, which in practise excludes application of the solution for free-vortex submersible pumps. A vital disadvantage of pressure installations used in waste water pumping stations is also the solids deposits in delivery pipeline and fittings after one of the two pumps brakes down. After the repair or replacement of the damaged pump it is necessary to clean carefully all fittings mounted. Mixing valves are also known, which are used for mixing the liquid before pumping. Such a valves are preferably mounted at the pump installation delivery side between the pumps and the non-return valves. European patent application no. EP 0 797 006 presents a solution, in which a pumping installation duck foot bend is integrated with a non-return valve and with a mixing valve, and at its outlet an additional non-return valve is mounted. The mixing valve is to the best advantage controlled with a floating ball valve body being hold in its open position by a pneumatically controlled piston rod. Once the ball valve body is released it is settled by the pumped medium flow in the mixing valve seat, thus closing it. In this case the mixing valve is connected to the pumping installation delivery side between the two non-return valves. This solution creates a self- blocking system, because after switching the pumps off, if the three valves keep tightness, the increased pressure is maintained between the valves. The floating ball valve body, pressed down by the pressure against the mixing valve seat, cannot be set up in open position, which is a condition for the mixing valve operation. As a result of deep-rooted analysis of the state-of-the-art and the research carried out on further reduction of the medium flow resistance in valves and on elimination of the ball valve body vibration, the new design of the valve was developed according to the invention. Additionally as a result of the same research work the method was developed, which enables the self-rinsing of the non-return valve with ball-shaped valve body. The characteristic feature of the valve according to the invention is the valve casing through-channel (conduit) in a form of a bend or an elbow and the fact that the straight line passing through the centre of the ball valve body, settled in fully open position, passes through the conduit (through-channel) both ends as well. The said line favourable intersects the through-channel axis at both its ends and passes through the opening of the deflected channel division wall at its symmetry axis. The valve casing through-channel can be equipped with an elbow-shaped (bend-shaped) cover connected in parallel to the deflected channel approximately along its whole width. The elbow-shaped, (bend-shaped) cover at the location, where the through-channel is interconnected with the deflected channel, has an internal edge, performing the role of a guide bar for the ball valve body and passing into the arc-shaped bulged internal surface of the deflected channel of radius equal to the radius of the deflected channel cross-section and being terminated with sharp front edge. The deflected channel can be made with a cleaning opening, closed with a cleaning cover. > In the advantageous device variant the elbow-shaded cover or the cleaning cover has a division wall interconnected to the cover and provided with an opening and one-sided supporting seat. The supporting seat front surface is facing the through-channel inlet and is located at equal distance, in the opposite direction, from the symmetry plane of cross-section of the elbow-shaped arc apex, which distance is lower than the ball valve body radius. The elbow-shaped (bend-shaped) cover can have at least one delivery branch of the through-channel, which axis to the best advantage coincides with the axis of the through-channel inlet or outlet or is at equal distances from these axes. Another variant has a division wall with an opening connected to the elbow-shaded cover or the cleaning cover, which opening is equipped with double-sided supporting seat dedicated for one of the two ball valve bodies to be alternatively settled in the valve fully open position. The said division wall is located at the symmetry plane of the said cover cross-section, and the through-channel has at every of its two inlets the ring-shaped seat located at equal distance from the channel outlet axis. In the special variant of the valve with a ball valve body in a form of a circuit switch, the through-channel has two inlets terminated with ring seats dedicated for one ball valve body or, alternatively, one of the two ball valve bodies to be settled in. In this variant of the valve with ball valve body the role of deflected channel division wall is performed, alternatively, by one of two inlets, and the outlet is located on the through-channel elbow (bend). The division wall opening creates with the valve casing through-channel the principally oval free passage area of width equal or greater than the through-channel width. In the special variant of the valve made according to this invention the elbow-shaped cover has a flange for a mechanism of adjustable pressure pad, which axis coincides with the through- channel inlet axis. The cover also can be made with assembling lugs located symmetrically in respect to its longitudinal section symmetry plane. The method of flushing according to this invention consists in the following sequence: after each single flow of the liquid through the valve casing conduit (through-channel) of the said ball valve body device, installed at the pumping installation delivery side, an alternate liquid flow is directed from an alternate pumping installation delivery side into the outlet or to the second (alternative) inlet of the said valve through-channel. At least a portion of the alternative liquid flow is directed to the outlet located at the through channel elbow (bend) under the deflected channel division wall. The liquid outflow from the elbow (bend) of the valve casing through-channel, installed at least at one of the two pumping installations delivery sides, is terminated by means of the mixing valve installed at this outlet. After closing of at least one mixing valve, installed at liquid outflow from the through-channel elbow (bend) in at least one of the two pumping installations delivery sides, an additional non-return valve is opened at the main outlet under the influence of the increased pressure on the pumping installation delivery side, which overcomes the counterpressure of the column of liquid behind the valve. The mixing valve is unblocked by gas bleeding from its control well when at the same time liquid flow is absent at both delivery sides of both pumping installations. The basic advantage of the valve according to this invention is the fact that between the through-channel and the deflected channel an area of free passage exists, which width is equal at least to the through-channel width, and that the channels are connected to each other at both ends. This minimises the possibility of blocking the valve by solid particles contained in waste water. In the basic valve variant, having one inlet and one outlet, the natural pressure loss, resulting from the local resistance in the tl-irough-channel elbow (bend) section, is used to keep the ball valve body in fully open position even at much lower liquid flows than in the case of classic valves, having inlet and outlet located in line. The main advantage of the flushing method according to this invention is the fact that in the waste water pumping station system with two pump installation, in the situation when one delivery side of pumping installation is in operation, at least a part of the deflected channel and the through-channel of the non-return valve with ball valve body, connected to the alternative delivery side of pumping installation, is flushed. The main outlet or the flushing outlet from the through-channel elbow (bend), located under the deflected channel division wall, enables the valve self-cleaning, as well as cleaning of its elbow (bend). If the mixing valves are applied at the outlets from the deflected channel elbows (bends), during the system start up the pumps in the pumping installations are not overloaded even without electronic devices for softened system start up and braking. The examples of the object of the invention are presented in figures, where fig.l presents a longitudinal section of the basic variant of the non-return valve casing; fig. 2 - a longitudinal section of the universal version of the non-return valve casing; fig. 3 - cross-section of the non-return valve casing at the symmetry plane according to fig. 2, appended with half- view of the division wall version as in fig. 1 and with half-section view of the division wall version as in fig. 2; fig. 4 - two non-return valves with connected mixing valves, installed at delivery sides of two pumping installations, along with the additional non-return valve end view and the vertical cross-section of one mixing valve; fig. 5 - non-return valve with two inlets and two ball valve bodies of the upper pumping station coupler, presented as the longitudinal cross-section and end view; fig. 6 - non-return valve with two inlets and two ball valve bodies of lower pumping station coupler, presented as half- view and half-section. The non-return valve with a ball valve body 1, shown in fig. 1, has a casing provided with a through-channel 2, with a ring seat 3 at the inlet, where the ball valve body is settled in the closed position. The casing is also provided with a deflected channel 4 of a diameter greater than the ball valve body 1 diameter, where the ball valve body 1 is placed when in the open position. At a place, where the deflected channel 4 is interconnected with the through-channel 2, the casing has an extended flow cross-section. The deflected channel 4 has a division wall 5 with an opening 6, fixing the ball valve body 1 in the fully open position. The division wall 5 is permanently attached to an elbow-shaped (bend-shaped) cover 7. Fig. 2 presents the universal variant of the non-return valve with the ball valve body 1, having two alternative inlets with ring seats 3. The elbow-shaped (bend-shaped) cover 7, connected in parallel with the deflected channel 4, constitutes the principal part of the elbow-shaped through-channel 2. This cover is provided with the division wall 5, permanently attached to the said cover and having the opening 6. In fig. 1 the division wall 5 with the opening 6 is provided with one-sided supporting seat 8 for the ball valve body 1 to be settled in, while in the fully open position. This seat's front plane is facing the through-channel 2 inlet and is located at equal distance in the opposite direction, from the symmetry plane of the cross-section of the elbow-shaped (bend-shaped) cover's 7 arc apex, which distance is lower than the ball valve body 1 radius. In fig. 2 the division wall 5 with the opening 6 is provided with a double-sided supporting seat 9 designated for the ball valve bodies 1 or 1' to be alternatively settled in. When the elbow-shaped (bend-shaped) cover 7 without the division wall 5 is used, then the non-return valve with one ball valve body 1 or with two ball valve bodies 1 and 1' can be applied as a circuit switch. In such a case one of the two inlets acts as the division wall with the opening, and the role of supporting seat is performed by the ring seat 3 of this inlet, as shown in fig. 6. The universal version of the non-return valve, as shown in fig. 2, can also perform the role of the non-return valve with one ball valve body 1. In this case possible assembly errors can be corrected by appropriate positioning the ball valve body 1. The flow direction can be changed using the same method without the need of the pipeline disassembling. The elbow-shaped (bend-shaped) cover 7 can have, besides the normal outlet, at least one delivery branch 10 of the through-channel 2, which to the best advantage is in line with the inlet or the outlet axis (fig. 4) or is perpendicular to these axes. In the case of universal version of the device, as in fig. 2, the delivery branch 10 can be used as the actual common outlet for the two inlets (fig. 5 and fig. 6). The elbow-shaped (bend-shaped) cover 7, at the location of its interconnection with the deflected channel 4, cuts the channel longwise approximately along all its width. As a result a smooth transition between the through-channel 2 and the deflective channel 4 is obtained, which minimises the resistance of the liquid flow through the valve. At the place, where the through-channel 2 merge with the deflected channel 4, as shown in fig. 3, an internal edge 11 is made, which acts as a guide bar for the ball valve body 1 at this part of its trajectory. The internal edge 11 converts to the arc-shaped bulged internal surface 12 of the deflected channel 4 of the radius equal to the radius of the deflected channel 4 cross-section and terminates with a sharp front edge 13. The deflected channel 4 can have a cleaning opening 14, closed from outside with a cleaning cover 15, preferable of the same diameter (fig. 5 and fig. 6). The division wall 5 with the opening 6 can be attached to the cleaning cover 15, as shown in fig. 5, rather than tj the elbow-shaped (bend-shaped) cover 7. Fastening the elbow-shaded cover 7 to the base and supporting structures is facilitated by assembling lugs 16, located symmetrically in response to the symmetry plane of the cover longitudinal cross- section. The beneficial feature of the valve according to this invention consists in the fact that its through-channel 2 is in the form of elbow (bend), and that the straight line passing through a centre of the ball valve body 1, while at the fully open position, crosses the through- channel at its ends. It enables to use the natural pressure loss, resulting from local resistance in the elbow (bend) part of the tl rough-channel 2, to keep the ball valve body 1 in the fully open position by unbalanced forces acting on it even at low liquid flow in the channel. The straight line, which contains the section connecting the centres of the ball valve body 1 in its extreme positions (closed and fully open), favourable crosses the tlirough-channel 2 axis at both its ends and passes through the opening 6 in the division wall 5 of the deflected channel 4, at its symmetry axis. Additionally the opening 6 in the division wall 5 is opened at one side, and from this side it forms together with the through- channel 2 a basically oval area of free passage of width equal at least to the channel width. The said free passage area protects the valve from blocking by solid particles contained in waste water. The valve according to this invention can be applied as a shut- off (stop) and control valve by installing at its inlet axis a flange 17 of an adjusting mechanism 18 of a pressure pad 19, as shown in fig. 6. The flange 17' in the elbow-shaped (bend-shaped) cover 7 can also be used as a delivery branch after disassembling the adjusting mechanism 18 of the pressure pad 19. The non-return valve according to this invention in the variant for liquids can be provided with the ball valve body 1 made of material of total density higher or lower than the flowing liquid density i.e. so called floating or sinking ball valve body. In case of a sinking ball the ring seat 3 should be placed below the division wall 5 , and in case of a floating ball - above the flap. It doesn't, however, apply to variants of non-return valves with two inlets with ring seats 3 as shown in fig. 5 and fig. 6, which can be provided with both the floating or sinking ball valve bodies 1 and 1' or the ball can be of the same density as the liquid flowing through the valve. This ball valve bodies can be made of metal or plastic as a shell covered with rubber or as a homogeneous mass of one material. The elbow-shaped (bend- shaped) cover 7 can be made of a different kind of material than the remaining part of the casing, for example cab be made of a wear- resistant material. The casing of the non-return valve according to this invention can be made as a metallic casting, for small diameters also as a forging or made of plastic using the injection moulding method. The method of flushing the valve, made according to the invention, is also the object of the invention. In fig. 4 two examples of pumping installations with submersible pumps are shown, with the pump delivery sides interconnected at the main outlet, where an additional non-return valve 20 is installed. Each of the two pumping installation delivery sides is equipped with the non-return valve according to this invention connected to the pump installation duck-foot bend , and equipped with a shut-off valve. The additional non-return valve 20 and the non-return valves according to this invention have a delivery branch 10. To the delivery branch 10 of the non-return valve, at each delivery side of the two pumping installations, a mixing valve 21 is connected. The mixing valve 21 has a control well 22 with adjustable gas inflow and outflow, controlling the liquid level in the well, where a ball control body floats. When the control well 22 is filled with liquid and none of the two pumps works the ball control body 23 is located outside the course of liquid flow through the mixing valve 21. After switching one of the pumps on, the liquid initially flows through the inlet of the non-return valve according to this invention, lifting the ball valve body 1, then through the delivery branch 10 emerging from the elbow (bend) of the through-channel 2 flows through the opening of the mixing valve 21. Then part of liquid stream supplied by the pump starts to flow in the direction of the nonreturn valve outlet and through the second delivery side of the second pumping installation comes to the outlet of the second non-return valve, where after flushing the valve upper and middle part flows out from the elbow (bend) of the through-channel 2 through the delivery branch 10 and the mixing valve 21 opening. If the mixing valves 21 openings are large enough, the additional non-return valve 20 installed on the main common outlet will not open, because the pressure at the pumping installation delivery sides is lower than the counterpressure behind the valve. In such a case the pump is not loaded during the start-up phase, because at the very beginning it doesn't have to overcome the backward pressure of the liquid column behind the additional non-return valve 20. In case of brake-down, when one of two pumps is out of order and the second one continues the operation, both delivery sides of both pumping installation will be flushed anyway. After some time, sufficient for mixing the pumped liquid and/or after the pump start-up phase, to the best advantage one of the two mixing valves 21 closes at first. The pressure at the pumping installation delivery sides increases. The mixing intensity of the second mixing valve 21 increases as well, and therefore the flushing intensity of the pumping installation second delivery side. If the pressure growth doesn't cause the opening of the additional nonreturn valve 20, then it opens only after the second mixing valve 21 is closed. However, if the pressure growth causes the additional nonreturn valve 20 opening, then the pressure in the mixing valve 21 increase even more, because the pump must additionally move the liquid column behind the additional non-return valve 20, which even further intensifies the flushing of the pumping installation delivery side and the mixing valve 21. If both pumps are in operation the flushing cycles alternately repeat. In order to close the mixing valve 21 the air or another gas should be led into its control well 22, what will cause the liquid level in the well to lower. The floating control body 23, being placed in the area of the flow through the mixing valve 21, will close the flow after setting at the outlet seat of the valve. The mixing valve 21 is unblocked by the gas bleed from its control well 22 with concurrent lack of liquid flow in both delivery sides of both pumping installation. The gas bleed is performed by means of a direct action valve, which is controlled by the pumped liquid pressure, or by means of an electromagnetic valve, which is connected to the control well 22 by a pneumatic control pipe 24. Constant and self-acting flushing of the pump installation together with the valve according to this valve considerable simplifies the system operation and increases the period between successive inspections. The valve according to this invention, because of its every-time flushing, is fully patent and not controlled pressure growths, caused by its partial patency loss are absent. The hydraulic hammers (shocks) caused by mixing valve 21 operation are softened by an air cushion in the control well 22, which acts as an air vessel absorbing hydraulic shocks. Thus the pumps operating in the two delivery pipelines of the two pumping installations are not exposed to overloading, on the contrary, the pump start-up is softened without the need for electronic soft-start devices. The described pumping installation according to fig. 4 is intended especially for high pumping capacity and pump power over 5 kW each. For lower pumping capacities and lower power of the pump the same objective can be achieved applying the solutions presented in fig. 5 and fig. 6. In these solutions one non-return valve according to this invention constitutes a coupler for two delivery sides, each equipped with a submersible centrifugal pump. When the valve is installed with the elbow-shaded (bend-shaded) cover 7 at the bottom the self- cleaning of the deflected channel 4 is facilitated with pumps operating alternatively. The valve according to this invention, as shown in fig. 5, constitutes the upper coupler to under-sling the two pumps by means of rigid pipes and catches. The valve according to this invention, as shown in fig. 5, is a double (twin) non-return valve with two ball valve bodies 1, 1' and two inlets with ring seats 3. During the liquid flow, coming from one of the inlets , the ball valve body 1 moves nearly horizontally inside the deflected channel 4 and settles on a double-sided supporting seat 9, opening the flow towards the outlet located below the deflected channel 4 and connected to the delivery branch 10 below the elbow-shaped (bend-shaped) cover 7. At the same time the alternative ball valve body 1' is settled in the ring seat 3 of the second inlet. When the at the first inlet side is switched off, the ball valve body 1 settles in the ring seat 3 of this inlet. When the second pump at the second inlet side is switched of , the alternative ball valve body 1' opens the passage through that inlet, and the liquid stream rinse out the impurities pushed into this valve section during the preceding pumping cycle, performed by the first pump, and most of it will be directed toward the delivery branch 10 outlet. Such cycles, being alternately repeated, effectively clean the deflected channel 4 as well as the through-channel 2 along its entire length. In this case the ball valve bodies 1, 1' are to the best advantage made as floating ones, and the upper edge of the deflected channel 4 is to the best advantage inclined downward towards the double-sided supporting seat 9. It ensures a quick inlet closing of the valve according to this invention after switching off the pump connected to this inlet, which was marked with the broken line. In fig. 6 a solution is shown, in which the valve according to this invention is made as the circuit switch with one or two ball valve bodies 1, 1'. During the liquid flow, coming from one of the inlets, the ball valve body 1 moves horizontally towards the second inlet, where closes the liquid flow toward the second inlet by settling upon its ring seat 3. After the second inlet is closed the liquid flows, downwards, toward the common outlet, made in the through-channel 2 elbow (bend), and upwards to the additional non-return valve 20 through the delivery branch 10. After the pump is switched off the additional non- return valve 20 closes the reverse flow, and the inlet from the switched off pump side remains open. When the second pump at alternative inlet is switched on, the ball valve body 1 is moved by the liquid flow toward the first inlet and is settled in its ring seat 3, and the impurities deposited in the deflected channel 4 are carried away by the liquid stream and directed to the common outlet made in the elbow (bend) of the through-channel 2. In such a way the self-acting flushing of the valve according to this invention is performed by alternate pumping with two pumps. When within the solution two ball valve bodies 1 and V are used in the deflected channel 4, then the deflected channel 4 self-cleaning process is intensified by the two balls striking against each other, and additionally the ball 1 and 1' impact at the two opposite seats is softened. The introduction of the two ball valve bodies 1 and 1' into the deflected channel 4 directs the flow toward the common outlet, what reduces the local pressure loss at the valve. -The same method can be applied in the basic valve variant, made according to fig. 5 with sinking ball and with application of the additional non-return valve with the floating ball installed at the common outlet from the delivery branch 10. In such a case the second ball is settled in the double-sided supporting seat 9, and during the alternate (reverse) flow is knocked out from this seat by the first ball. The elbow-shaped (bend-shaped) cover 7 can have symmetrical recesses for the ball valve body 1, and the one-sided supporting seat 8 can be made as a homogeneous part with the deflected channel 4 and/or with the split place near the top of the sharp frontal edge 13, which was marked with bold broken line. Such a realisation enables any assembling direction of the elbow-shaped (bend-shaped) cover 7 without any influence on the valve operation. In a similar way the valve according to fig. 2 can be made, whereas the additional non-return valve 20 of a shortened design has one-sided supporting seat 8 of shortened construction, and its cover has adequately profiled internal edge widened at its ends in order to absorb the impact from the ball during the valve opening. The shortened construction of the valve according to this invention in particular can be used in case when the pressure pad 19 is used, compensating in this way the additional force carried by the elbow- shaped (bend-shaped) cover 7 or unifying the valve length with typical elbows (bends). The side effect of the shortened valve construction is the increase of local pressure loss, enabling the valve full opening at minimal flow. The design of the valve according to this invention enables its repair by seat reaming and/or bushing without disassembling from the pipeline or by reversing the elbow- shaped (bend-shaped) cover 7, and then reversing the valve casing. Additionally the profiled internal edge 11 enables a smooth transition of the ball valve body 1 to its extreme positions (closed and fully open) without significant resistance and vibrations, which is marked with the broken line in fig. 1 and fig. 2. The valve according to this invention can be applied in many combinations in the delivery and suction pipelines. The additional non-return valve 20 in fig. 6 can be connected to the second valve of this kind by means of a "T" joint with a gate valve possible installed at its inlets, whereas the additional non-return valve 20 in fig. 4 can be connected to second non-return valve of this kind by means of a "T" joint and two gate valves installed at its inlets. The valves according to this invention shown in fig. 4 and fig. 6 can be fixed by means of the assembling lugs to adequate supporting structures, to the base or to supporting blocks or can be underslung by means of the prolonged screws fixing the elbow-shaped (bend-shaped) cover 7 as shown in fig. 5 and fig. 4 in half-section view A- A. The method according to this invention as in fig. 4 can be applied both in the delivery pipelines of wet pumping station and in the delivery pipelines with separated dry section for fittings, with a mixture sedimenting easily in the delivery pipelines The examples of the valve realisation and examples of the method according to this invention presented above do not cover all the possibilities of the valve realisation an application embodied with patent claims from 1 tol6.

Claims: Patent claims 1. A non-return valve with at least one ball valve body, having a casing provided with a through-channel with an outlet and at least one inlet with a ring seat, on which the ball valve body settles in the valve closed position, and additionally having a deflected channel of a diameter greater than the ball valve body diameter, where the ball enters in the valve open position, while at the inlet, where the through-channel merges with the deflected channel, the casing has an extended cross- section of flow area, and the deflected channel has a division wall with an opening connected to the through-channel outlet, which division wall fixes the ball valve body in a fully open position, whereas a line section connecting the ball valve body centres at its extreme positions (closed and fully open) is placed along all its length inside the deflected channel, characterised in that the through-channel (2) of the valve casing has a form of an elbow or a bend, and that a straight line passing through the ball valve body (1) centre, when the ball is in the fully open position, passes the through channel (2) at both its ends. 2. The valve according to the claim 1, characterised in that the straight line containing the line section, connecting the ball valve body (1) centres at its extreme positions (closed and fully open), cuts the through-channel (2) axis at both its ends and passes the opening (6) of the deflected channel (4) division wall (5) at its symmetry axis. 3. The valve according to the claim 1, characterised in that the through-channel (2) has an elbow-shaped (bend-shaped) cover (7), being in parallel coupling to the deflected channel (4) approximately along its full width. 4. The valve according to the claim 3, characterised in that the elbow-shaped (bend-shaped) cover (7) has, at the place where the through-channel (2) merges with the deflected channel (4), the internal edge (11), acting as a guide bar for the ball valve body (1), which . edge passes into the arc-shaped bulged internal surface (12) of the deflected channel (4), of the radius equal to the radius of cross-section of the deflected channel (4), and terminated with a sharp front edge (13). 5. The valve according to the claim 1, characterised in that the casing deflected channel (4) has the cleaning opening (14) closed with the cleaning cover (15). 6. The valve according to the claim 3 or 5, characterised in that the division wall (5) is attached to the elbow-shaped (bend- shaped) cover (7) or to the cleaning cover (15), having the opening (6), provided with the one-sided supporting seat (8), whereas the seat frontal plane is facing the through-channel (2) inlet and located at equal distance in the opposite direction, from the transversal section symmetry plane of the elbow- shaped (bend-shaped) cover 7 bow apex, which distance is lower than the ball valve body (1) radius. 7. The valve according to the claim 3, characterised in that the elbow-shaped (bend-shaped) cover (7) has at least one delivery branch (10) of the through-channel (2), whereas the symmetry axis of at least one of these branches to the best advantage coincides with the through-channel (2) inlet or outlet axis or is at equal distances from these axes. 8. The valve according to the claim 3 or 5, characterised in that division wall (5) is connected to the elbow-shaped (bend- shaped) cover (7) or to the cleaning cover (15), which division wall has an opening (6) with double-sided supporting seat (9) intended for one of the two ball valve bodies (1), (T) to be alternatively settled in at the fully open position, wherein the division wall (5) is placed at the symmetry plane of the cover or cleaning cover cross-section, and the through-channel (2) has at each of its inlets the ring seat (3) at equal distance from the channel outlet axis. 9. The valve according to the claim 1, characterised in that it is made in the form of the circuit switch, whose through-channel (2) has two inlets with the ring seats (3) intended for one ball valve body (1) or alternatively for one of the two ball valve bodies (1), (1') to be settled in, wherein the role of the deflected channel (4) division wall (5) is alternatively performed by one of the inlets, and the outlet is located at the elbow (bend) of the through-channel (2). 10. The valve according to the claim 3 or 5, characterised in that the division wall (5) opening (6) constitutes together with the through-channel (2) a basically oval free passage area, of width equal or greater than the through-channel (2) width. 11. The valve according to the claim 3, characterised in that the elbow-shaped (bend-shaped) cover (7) has the flange (17) for the adjusting mechanism (18) of the pressure pad (19), whose axis coincides with the through-channel (2) inlet axis. 12. The valve according to the claim 3, characterised in that the elbow-shaped (bend-shaped) cover (7) has the assembling lugs (16) located symmetrically in respect to the symmetry plane of the cover longitudinal cross-section. 13. The method of flushing of at least one non-return valve with a ball valve body, connected to two delivery sides of two pumping installations, whose casing has a through-channel with an outlet and with one or two inlets, each having a ring seat intended for the ball valve body to be settled at the closed position, and additionally has a deflected channel of a diameter greater than the ball valve body diameter, where the ball is located at the valve open position, whereas at the inlet, at the location where the deflected channel merges with the through-channel, the casing has extended flow area cross- section, and the deflected channel has a division wall with an opening, connected to the through-channel outlet, which division wall fixes the ball valve body in the fully open position, while the line section connecting the ball valve body centres in its extreme positions (closed and fully open) along its full length is placed inside the deflected channel, characterised in that after each single liquid flow through the casing through-channel (2) of the valve with the ball valve body (1), installed at the pumping installation delivery side, the alternative liquid flow is directed from the delivery side of the alternative pumping installation into the outlet or into the second (alternative) inlet of this valve through-channel (2), while at least part of the alternative liquid flow is directed to the outlet located at the through-channel elbow (bend) below the division wall (5) of the deflected channel (4). 14. The method according to the claim 13, characterised in that the liquid outflow from the through-channel (2) elbow (bend) of the valve casing, installed at least at one of two delivery sides of two pumping installation, is interrupted by means of the mixing valve (21) installed at this outlet. 15. The method according to the claim 14, characterised in that after closing of at least one mixing valve (21) installed at the liquid stream outflow from the through-channel (2) elbow (bend) at least at one outlet of two pump installations delivery sides, the additional non-return valve (20) opens at the main outlet under influence of the pressure growth at the pumping installation delivery side, overcoming the backward pressure of the liquid column behind this valve. 16. The method according to the claim 14, characterised in that the mixing valve (21) is unblocked by the gas bleed from its control well (22) when at the same time there is no liquid flow in neither delivery side of the two pumping installations.

Inventors: SZUSTER MIROSLAW, SZUSTER, MIROSLAW
Applicants: SZUSTER MIROSLAW, SZUSTER, MIROSLAW
Application year: 2001
Main classification: F16K15
IPC codes: F16K15