RU2822725C2 - Gate valve - Google Patents

Abstract

FIELD: pipelines.

SUBSTANCE: invention relates to pipeline valves. In the proposed slide gate valve, the sealing circuit of the gate, seats and fastening threaded flanges is created by separate sealing elements. Two of which are located on end surfaces of seats, with direct contact with progressively moving gate. Another two create an axial force of pressing the seat and at the same time primary sealing of through holes from the inner cavity of the body and the external medium. Two more are located on the outer diameter of the seats mating with the through hole. Disk position indicator made of antifriction plastic which does not require lubrication during the whole service life, when moving along the thread in the axial direction, the pins of the threaded cover of the gate valve with indicators "O": open and "C": closed are kept from turning.

EFFECT: invention is aimed at simplifying the design of the bearing assembly of the drive for moving the gate, and as a result, reducing the manufacturing labour intensity and cost of the gate valve, improved reparability in field conditions without complete disassembly of the gate valve, increased reliability of the shut-off group, increased stiffness of the gate position indicator.

1 cl, 4 dwg

Description

The invention relates to the oil and gas, chemical and hydrocarbon processing industries, namely to the field of valve engineering; it can be used as shut-off valves for oil, gas and pipelines transporting chemically aggressive liquids, wellhead fittings, tanks and other places for hermetically sealing the flow area.

Transportation via pipelines from hydrocarbon production sites often occurs in harsh climatic conditions, in places with limited access to shut-off valves and with significant physical labor costs to operate them. The production process requires the need to reliably shut off the flow of liquids with a high content of salts and mechanical impurities, however, the presence in classical designs of oil-filled steel valves (hereinafter referred to as OMS) of a large free space under the gate, which is not sufficiently protected from penetration at the time of opening and closing the shut-off element, leads to the accumulation of deposits, affecting the performance of all valve elements. Accelerated wear of the shut-off parts of the valve, the impossibility of complete closure due to accumulated deposits in the valve space, low (especially in the field) maintainability of most of the shut-off elements, the need to create environmentally friendly, reliable and long-lasting shut-off devices, which ultimately improve the economic performance of equipment, working conditions and environmental safety, determine the greatest relevance of the development of new, original designs of gate valves.

A gate valve is known from the prior art (RU No. 2342579, MPK F16K 3/02, 27/04. 3/30, published on 08/27/2008), containing a body with a passage channel for the working medium and an under-gate space, a lifting gate with a through passage hole and end sealing surfaces, sealing seats, elastic O-rings and gate guides. The guide plates are integral with the sealing seats and are equipped with sealing surfaces for the gate. Elastic rings are located on the gate. Additional elastic sealing rings are installed along the periphery of the end sealing surfaces of the gate. The latter isolate the valve space from the flow part of the housing throughout the entire stroke of the valve. [1].

The disadvantage of the device is: the complexity of the design and, as a consequence, the high labor intensity of manufacturing, a large number of elements (adjusting stops for prestressing the seats) that need to be sealed from the external environment cause low environmental safety. The presence of a retractable spindle reduces operational safety at high pressures.

A gate valve is known (RU No. 2578548 MPK F16K 3/02, 27/04. 3/30, published 08/27/2016), containing a body made of rolled steel. In the middle part of the body, along the outer surface, there are mutually perpendicular planes with respect to the vertical and horizontal axes, two of them are located opposite to each other, equipped with mounting holes, the body is equipped with a lower cover fixed from below, while the seats are located between the springs, disk rings and sealing rings, in addition, the rod has sections with trapezoidal left and metric right threads, while on the top cover there is a yoke, made in the form of a sleeve equipped with a stepped inner surface and a base, an oiler is attached above the base, one of the steps of the inner surface of the said yoke is equipped with a thread, inside The yokes from bottom to top are arranged accordingly and placed: a block, a bearing, a fusible insert, a pressure nut equipped with a thread on the outer surface and a groove with a sealing ring placed in it on the inner surface; on the end surface, made as a step of the said yoke, a position indicator is located and fixed on the flywheel side rod, through holes are made in the lower and upper covers, located perpendicular to the vertical axis of the valve, in which discharge valves are installed with the ability to move [2].

The disadvantage of the device is: the complexity of the design and geometry of the housing in particular, as a consequence of the high labor intensity of manufacturing, a large number of elements. Lack of hermetically sealed protection of the internal cavities of the indicator from atmospheric precipitation and, as a consequence, the possibility that the hole in the gate does not coincide in the open position of the valve stem channels due to icing or the ingress and accumulation of solid dust particles.

A gate valve is known (RU No. 2547200, MPK F16K 3/06, published 04/10/2015), consisting of two half-bodies connected to each other, in the bore of one of the half-bodies there is a gate with a radius bore, in which a toothed notch is made, with which The teeth of the drive shaft, passed through the bore in which the thrust bearing is located, are kinematically connected with the plain bearing inside. At the end of the drive shaft there is a hole in which the ball is placed, supported by an internal conical groove in the body of the thrust bearing. At the end of the thrust bearing there are transverse grooves, and on the cylindrical surface there are longitudinal grooves for supplying lubricant from the oiler to the rubbing surfaces of the gearing. The gate is installed on the axis of rotation and contains pockets on the periphery of the radius boring. In the axial channels of the half-bodies, spring-loaded seats are installed, pressed against the gate, ensuring hermetically sealed contact. When the drive shaft rotates, the flow of working fluid is opened and closed by a gate that rotates on an axis. Mechanical impurities and scale entering the lubricant accumulate in pockets at the periphery of the radius boring [3].

With minimal volumes of free space under the gate, a significant disadvantage of disc gate valves is the low load capacity along the axis of the nozzles, which is due to the design features of the valve and, as a consequence, the possibility of jamming of the disc gate when performing technological operations, especially as part of Christmas tree fittings.

The closest technical solution to the claimed invention, adopted as a prototype, was a gate valve (No. 2730895 RU, SPK F16K 3/02; 3/16, published on August 26, 2020 Bulletin No. 24), containing a body with coaxial stepped passage holes, an internal cylindrical a boring perpendicular to the passage holes, mounting flanges located opposite to each other and made symmetrically about the vertical axis, in the lower part of which there is a threaded hole perpendicular to the axis of the passage holes and a valve is installed to relieve excess pressure. Seats, gate valve with running nut and drive screw. Guide inserts installed in the cylindrical bore of the body. They are pressed by the top cover in which the stuffing box assembly is located, the pressing force of the stuffing box unit is adjusted by a pressure nut, a threaded hole is opened on the periphery and a discharge valve is installed, a castle nut with a bearing unit is installed on the thread in the upper part, crackers, crackers are fixed through a groove in the drive screw its axial position relative to the body. When the drive screw rotates clockwise, the flywheel moves the running nut and, accordingly, the gate from the open to the closed position. The exact alignment of the axes of the barrel passages and the hole in the gate in the “Open” position is ensured by adjusting the adjusting ring. The bearing assembly is lubricated through a grease nipple installed in the castle nut; to prevent possible loosening of the castle nut during operation, it is secured with a locking screw; to prevent the ingress of atmospheric precipitation, a sealing element is installed in the upper part of the castle nut. At the outer end of the castle nut there is a valve position indicator - a petal type, made of elastic material and without hidden cavities, which eliminates the accumulation of condensate and precipitation and the possibility of jamming of the indicator when it moves [4].

The disadvantage of the valve is the rather complex design of the bearing and stuffing box assembly and, as a consequence, high labor intensity. Low maintainability in field conditions - the impossibility of direct control and diagnosis of the main sealing surfaces in the body under the seat. Insufficient rigidity of the blade position indicator of the gate.

The technical problem to be solved by the claimed invention is to simplify the design of the bearing assembly of the valve movement drive, and as a result, reduce the labor intensity of manufacturing and the cost of the valve. Improved maintainability in the field without completely disassembling the valve. Increasing the reliability of the locking group. Increasing the rigidity of the gate position indicator.

The stated technical problem has been solved: due to the fact that in a gate valve containing a body made of rolled stock, having coaxial stepped passage holes, an internal cylindrical bore perpendicular to the passage holes, mounting threaded flanges located opposite to each other and made symmetrically about the vertical axis, in the lower part of which has a threaded hole on the axis of movement of the gate and a valve is installed to relieve excess pressure when replacing lubricant, a seat, a gate with a nut and a drive screw. Guide inserts, made monolithically of a composite antifriction material, installed in a cylindrical bore of the body, are pressed by an upper threaded cover, in which a double sealing circuit is placed and a cageless bearing is formed from free rolling elements (hereinafter referred to as STC), a threaded hole is opened on the periphery and a discharge valve is installed for lubrication bearing unit. At the top of the threaded cap there is a pressure valve for replenishing or replacing lubricant in the valve body. The flange of the drive screw is equipped with cotters, which, by means of adjustment, ensure the required axial clearance in the cageless bearing and the alignment of the hole in the gate with the common axis of the inlet and outlet pipes of the valve. When the drive screw is rotated clockwise, the flywheel causes translational movement of the running nut and, accordingly, the gate from the open to closed position; the left direction of the thread for structures with a non-retractable spindle ensures the mnemonic principle established by GOST for gate valves, and unloading onto one cageless rolling bearing ensures minimum force on the flywheel, to prevent possible unscrewing of the threaded cover during operation, it is secured with a locking screw; to prevent the ingress of precipitation, a sealing element is installed in the upper part of the cover. At the outer end of the cover there is a hard disk indicator of the position of the gate, which does not have hidden cavities, which eliminates the accumulation of condensation and precipitation and the possibility of jamming of the indicator when it moves and, as a result, the gate does not reach one of the extreme positions “open - closed”.

What distinguishes the valve from its known analogues is that the body has a cylindrical bore, without ledges, perpendicular to the axis of movement of the gate, into which seats with a double sealing contour are mounted, and the contour located in the end part of the seat creates preliminary pressure on the sealing part of the seat to the gate and the primary sealing of the connection, and the design of the valve allows its installation and dismantling with the gate installed, which allows for defect detection and replacement of seats without completely disassembling the valve in the field. Also, unlike analogues that have two thrust bearings in the design, a double sealing circuit is placed in the upper threaded cover and one cageless rolling bearing is formed from free rolling bodies (FRB), and an integrated disk position indicator, which is more rigid in design, is installed on the outer end of the cover gate

The search carried out by the authors in the information sources available at the date of filing the application did not reveal similar technical solutions that have all the distinctive features of the claimed device, which confirms that the invention meets the criteria of “novelty” and “inventive step”.

The design of the valve is illustrated by drawings, where in Fig. 1 shows a diagram of a gate valve; in fig. 2 - shows the cross section of the valve; in fig. 3 - shows a longitudinal section along the passage holes. In fig. 4 - extension of the disk indicator and a section perpendicular to axis 5 along a cageless rolling bearing made of STC with a mounting channel for balls.

The gate valve contains a body -1, which has coaxial stepless passage holes -2, with the possibility of processing on one side in one installation, in which valves -3 are installed, two of which are mounted on the end surfaces -4 and -5 - sealing elements - 6 and -7 with direct contact with a progressively moving gate -8, and the sealing element -9 - a standard O-ring, creates an axial pressing force on the seat and performs the function of primary sealing of the passage holes -2 from the internal cavity of the body -1, and on the outer diameter of the mating with passage hole -2, secondary sealing circuit -35. In the body -1, there is an internal cylindrical bore -2, perpendicular to the axis of movement of the gate -11, with fastening threaded flanges -12, located opposite to each other, and made symmetrically relative to the vertical axis 11, in the lower part of which there is a threaded hole -13, on the axis -11 and a valve -14 is installed to relieve excess pressure during the operation of replenishing or replacing lubricant. A nut -15 is mounted in the gate - 8, and a drive screw -16. A flywheel -37 is installed in the upper part of the screw. Guide inserts made of composite antifriction material -17 installed in the cylindrical bore of the body -18. They are pressed by the upper threaded cover -19, in which a double sealing circuit 20 and 21 is placed and a cageless rolling bearing -22 is formed, from STC (free rolling elements) -23, for mounting and forming a cageless bearing in the cover there is a threaded hole -40, which After installing the balls, it is closed with a -36 screw. The -24 threaded hole is exposed on the periphery. and a -25 discharge valve is installed to lubricate the bearing assembly. At the top of the threaded cap -19 there is a discharge valve -26 for replenishing or replacing lubricant in the valve body. The joint between the cover -19 and the body -1 is sealed by sealant -38. On the collar of the drive screw -16 there are crackers -27 installed. Using the fitting method, the crackers provide the necessary axial clearance in the cageless bearing -22, and the coincidence of the passage hole in the gate -28 and the common axis -29, the inlet and outlet pipes, and the valve. To prevent possible unwinding of the threaded cap -19, during operation it is fixed with a locking screw 30, to prevent the ingress of atmospheric precipitation, a sealing element 31 is installed in the upper part of the cap. At the outer end of the threaded cap -32, there is an integrated disk indicator for the position of the gate valve -33, which moves as a result of rotation of the screw along the thread -34 in the axial direction, which is prevented from turning by fingers -38 with the indicators “O” - open and “Z” - closed on them.

The gate valve works as follows. By rotating the flywheel 37, the torque was transmitted to the screw 11, which is installed in the upper threaded cover 19 with a cageless rolling bearing 22 integrated into it; the connection does not allow the screw 16 to move along the axis 11. When the screw 16 rotates, the running nut 15 moves along the axis 11, which, in turn, moved the gate 8. At the same time, the disk indicator of the position of the gate 33 moved along the axis 11. The closing of the passage channel 2 was carried out by rotating the flywheel 37 clockwise until the gate 8 stops at the lower end of the cylindrical bore of the body 1, while the pointer moved to the corresponding position - “closed”. The gate valve is opened by turning the flywheel 27 counterclockwise until the gate 8 stops in the adjusting nuts 27, and the dial indicator moves to the corresponding “open” position.

Information sources

1. Pat. RU 2342579 C2 Russian Federation, IPC F16K 3/02, 3/316. Gate valve / Sevastyanikhin G.P., Larionov V.B., Izmailova V.V., Bondarev I.V.; applicant CJSC NPF "Central Design Bureau of Valve Engineering". No. 2006145097/06; application 12/18/2006; publ. 12/27/2008. Bull. No. 36.

2. Pat. RU 2578548 C1 Russian Federation, IPC F16K 3/02, 27/04, 3/30. Gate valve / Matveev A.V., Ufimtsev V.A., Guryanv A.V.; applicant Ufimtsev V.A., Guryanv A.V. No. 2014151515/06; application 12/18/2014; publ. 03/27/2016. Bull. No. 9.

3. Pat. RU No. 2547200 Russian Federation, IPC F16K 3/06. Disk valve / Bakirov D.R., Bakirov D.R., Mashkov V.A., Plekhanov E.N.; applicant Arliz LLC. No. 2014104175/06; application 02/07/2014; publ. 04/10/2015.

4. Pat. RU 2730895 C1 Russian Federation, IPC F16K 3/02 F16K 3/316. Gate valve / Bezumov A.A., Repko A.V.; applicant Bezumov A.A., Repko A.V. No. 2019119364; application 06/19/2019; publ. 08/26/2020. Bull. No. 24

Claims (1)

A gate valve containing a body having coaxial stepless bores, seats, sealing elements, a flat gate with a nut and a drive screw, in the upper part of which a disk indicator of the gate position and a flywheel are installed on the thread, mounting threaded flanges, a valve for releasing excess pressure and a threaded a cover with a cageless bearing, protected by sealing contours from the internal cavity and precipitation, a discharge valve, cylindrical fingers with marked “O” and “Z” indicators, characterized in that the sealing contour of the gate, seats and mounting threaded flanges is created by separate sealing elements, two of which are located on the end surfaces of the seats, with direct contact with the translationally moving gate, two more create an axial pressing force on the seat and at the same time primary sealing of the passage holes from the internal cavity of the body and the external environment, two more are located on the outer diameter of the seats, mating with the passage hole, and made of anti-friction plastic that does not require lubrication during the entire service life, the disk indicator of the gate position, when moving along the thread in the axial direction, is kept from turning by the fingers of the threaded valve cover with the indicators “O” - open and “Z” - closed.