RU221675U1 - GATE VALVE FOR INSTALLATION OF SLOW COKING - Google Patents

Abstract

The utility model is intended for installation in the lower and upper parts of the chamber of a delayed coking unit at an oil refinery (refinery). Gate valves serve as automatic hatches for a delayed coking unit and are designed for the safe unloading of coke from the unit after completion of the coking process of heavy petroleum products. The technical result is an increase in operational characteristics, including durability of the structure, trouble-free operation, tightness of the valve, ensuring operation at high temperatures, and increasing the reliability of the structure. A gate valve contains a body, seats, a gate purge system, and an upper and lower cover are attached to the body on both sides. 2 salary f-ly, 7 ill.

Description

The utility model is intended for installation in the lower and upper parts of the chamber of a delayed coking unit at an oil refinery (refinery). Gate valves serve as automatic hatches for a delayed coking unit and are designed for the safe unloading of coke from the unit after completion of the coking process of heavy petroleum products.

A gate valve is known (RU 139071, publ. 04/10/2014 Bulletin No. 10), which consists of a welded body with reinforcing ribs and a cover, a gate valve is placed inside the body between two seats with seals, a spindle is installed in the upper part of the body, one end is inside the body connected to the valve, and the other passing through the cover and stuffing box for connection with the valve control element, the cover is made of rolled sheet metal and forging with lugs and two flanges, one for fastening to the body, the other for installing a stand with a spindle inside and a yoke assembly, in the stuffing box there is a drain valve and a discharge valve, inspection windows are located in the rack opposite the stuffing box, inside the housing there is a drainage pipeline equipped with a ball valve leading out, there is a leakage control device consisting of pressure sensors, ball valves, separation vessels, fittings, pipelines and heating systems. The disadvantage of this technical solution is that it cannot be used in delayed coking units.

The closest technical solution is a gate valve (RU 55915, published August 27, 2006 Bulletin No. 24), containing a body made of two detachable parts, connecting pipes fixed to the body, forming at least one channel, and a seat formed at the inner ends of the pipes , located inside the housing and covering the seat, and a drive for moving the gate across the channel. The gate is equipped with a position sensor. Inside the body, around the seat, there is a groove that communicates with the source of the working medium supplied under pressure to flush (purge) the gate. The disadvantage of this technical solution is that it cannot be used in delayed coking units.

The objective of the stated technical solution is to develop a gate valve with the ability to be installed on a delayed coking chamber and operate at high temperatures, ensuring tightness and the ability to operate at coke unloading.

The technical result is an increase in operational characteristics, including durability of the structure, trouble-free operation, tightness of the valve, ensuring operation at high temperatures, and increasing the reliability of the structure.

The technical result is achieved in that the gate valve contains a body, seats, a gate located inside the body and a gate covering the seat, a gate position sensor, a gate purge system, the body is flat, the top and bottom covers are attached to the body on both sides, the top cover is covered by an installed flat cover , the lower cover is closed by an installed blind plug, the body has an upper movable and lower fixed seat, the lower seat has sealing rings, a clamping ring and a ring are attached to the upper seat, while the upper movable seat and ring are connected to the clamping ring by means of a bayonet connection using hooks, located on the rings, the movable upper seat and the ring are connected to each other using studs and nuts and form a stuffing box with sealing rings, and the clamping ring of the upper seat is stationary and pressed against the body, springs are installed between the movable seat and the clamping ring in the holes, upper and lower the covers have holes in the upper part for supplying steam, and in the lower part - holes for condensate removal; a casing, which is a flat box, is attached to the body from the side of the bottom cover using a flange; from the side of the top cover, a spindle is connected to the gate, made with the possibility of connection with a valve control element, an adapter is installed on the flat cover, on which the drive and indicator stands are installed, while on the indicator stand there is a valve position indicator in the form of an arrow and gate position sensors, at the junction of the spindle and indicator with the top cover of the housing there are gland units, consisting of rings, packing bushings, gland flanges, the working surfaces of the gate are nitrided.

The utility model is illustrated by drawings, which show:

in fig. 1 - cross-sectional view of a gate valve

in fig. 2 - enlarged fragment of the shutter assembly,

Fig.3 is an enlarged fragment of the electric drive spindle oil seal assembly,

Fig.4 is a top view of the valve with a position indicator and seal fastenings,

Fig.5 is an enlarged fragment of the seal flange fastener with a set of disc springs for the locking rod,

Fig.6 is an enlarged fragment of the seal flange mounting with a set of disc springs,

in fig. 7 - enlarged fragment of the locking rod with sensors,

where 1 - body; 2 - top cover, 3 - bottom cover, 4 - cover, 5 - blind plug, 6 - adapter; 7 - gate; 8 - hairpin; 9 - nut; 10 - gasket; 11 - movable saddle; 12 - lower saddle; 13 - pressure ring; 14 - ring; 15 - sealing ring TRG; 16 - sealing ring TRG; 17, 18 - TRG sealing rings; 19 - spring; 20 - bracket; 21 - bracket pin; 22, 23 - spindle; 24 - locking rod; 25 - spindle coupling; 26 - coupling pin; 27 - drive rack; 28 - pointer stand; 29 - gate casing; 30 - gate guide; 31.32 - stuffing bushing; 33 - guide bushing; 34 - locking pin; 35, 36 - oil seal flange; 37.38 - disc spring; 39 - cotter pin; 40 - oil seal stud; 41 - oil seal nut; 42 - threaded bushing; 43 - electric drive; 44 - blind flange; 45, 46 - gasket; 47 - pointer; 48, 49 - gate position sensor, 50 - hole for cooling water inlet, 51 - hole for cooling water outlet, 52 - hole for safety valve, 53 - hole for steam supply, 54 - hole for condensate drainage.

The gate valve consists of a cast flat body 1, to which, on both sides, through a gasket 10, flat cast caps, top 2 and bottom 3, equipped with stiffening ribs, are attached using pins 8 and nuts 9. The top cover 2 is covered by an installed cast flat cap 4, and the bottom cover 3 is closed by an installed blind plug 5. Making covers 2 and 4 and covers 3 and plug 5 separate ensures high manufacturability of the design compared to making these parts solid cast in analogues, and such parts are also unified. An adapter 6 is installed on the cover 4, which performs the function of a box for cooling the stuffing box assembly with water through hole 50 for inlet of cooling water and hole 51 for outlet of cooling water. Also installed on the adapter 6 are the drive racks 27 and the indicator 28. The indicator rack 28 serves to accommodate the valve position indicator 47 in the form of an arrow and the gate position sensors 48 and 49. It is also possible to design the valve, where in the rack, in addition to the indicator, there is a locking rod 24, connected to the guide sleeve 33, with a locking pin 34 and position sensors 48 and 49. The locking pin 34 serves as a mechanical lock for the gate 7 in extreme positions to ensure safety.

The gate valve assembly consists of a gate 7, the working surfaces of which are nitrided in order to increase surface hardness, wear resistance, heat resistance, fatigue strength and corrosion resistance in accordance with clause 1.1. RD-50-186-80. The gate, due to the pressure of the medium and springs 19 acting on the upper movable seat 11, is pressed against the lower seat 12, the working surface of which has a hard surfacing of stellite 6 with a minimum thickness of 3.5 mm, which provides high hardness, protection against corrosion and prevents resulting in the formation of damage from solid coke particles on the sealing surfaces. The lower seat 12 is fixedly installed in the housing 1 and due to the sealing rings made of thermally expanded graphite (TEG) 16, a seal is ensured between the lower seat 12 and the housing 1. Most often, two rings 16 are used, which is the optimal number for sealing and financial costs.

The upper seat consists of three parts: a movable seat 11 with hard surfacing stellite 6 with a minimum thickness of 3.5 mm, a ring 14 and a pressure ring 13. The movable seat 11 and ring 14 are connected to each other using studs and nuts and form a stuffing box assembly with rings sealing 15 from TRG, which ensures sealing of the gap between the movable seat 11 and the pressure ring 13. The pressure ring 13 is stationary, it is pressed against the body 1 through gaskets 46 using the flange of the coke chamber.

Surfacing has a minimum thickness of 3.5 mm, below which the required hardness will not be achieved due to mixing of materials.

The movable seat 11 and ring 14 are connected to the clamping ring 13 by means of a bayonet connection using hooks located on rings 13 and 14 and have mobility in the vertical direction due to the presence of gaps between the hooks. Between the movable seat 11 and the pressure ring 13, in the holes located in the rings, springs 19 are installed, which provide constant pressure of the movable seat 11 to the gate 7 to ensure tightness.

Thus, ring 14 presses the stuffing box rings 15 to the seat 11, and the clamping ring 13 holds the entire structure of the assembled seat in the body; the seat 11 is pressed against the gate by means of springs, which at one end rest against the clamping ring 13, and at the other against the seat 11.

To prevent the working medium and coke from entering the internal cavity of the valve, as well as to ensure the tightness of the valve and prevent the formation of coke between the seats 11 and 12 and the gate 7, steam is constantly supplied into the internal cavity of the valve through holes 53 in the upper 2 and lower 3 covers, located above. To drain condensate, in the upper 2 and lower 3 covers, there are holes 54 on the bottom side for connecting the condensate drainage system.

Also, to prevent coke from entering the internal cavity of the valve at the time of opening and closing the gate, the design provides a casing 29, which is a flat box welded from sheet steel, open on both sides, the casing 29 is attached to the body 1 using a flange located on the casing . The casing 29 covers the gate 7 from the side of the bottom cover 3. Between the casing 29 and the gate 7, through small gaps, using steam, coke particles and dust are blown off from the gate 7, which provides protection against coke getting into the internal cavity of the valve when the gate is opened and closed. When the gate 7 moves “open-closed”, the casing 29 also serves as a guide surface for the gate 7 and works in conjunction with the gate guide 30 installed on the top cover 2, which serves to prevent lateral displacement of the gate.

Ensuring tightness along the drive spindle 22 is ensured using an oil seal assembly consisting of TRG rings 17, a packing sleeve 31, an oil seal flange 36, which press the rings 17 using an oil seal pin 40 and an oil seal nut 41, as well as a set of disc springs 37 to ensure constant pressure sealing rings 17.

Ensuring tightness along the indicator rod and locking 24 is ensured using an oil seal assembly consisting of TRG rings 18, a packing sleeve 32, an oil seal flange 35, which presses the rings 18 using an oil seal pin 40 and an oil seal nut 41, as well as a set of disc springs 38 to ensure constant pressing of the sealing rings 18.

To ensure stable tightness and prevent excessive heating of the spindles 22 and 23 and the electric drive 43, the stuffing box assembly of the drive spindle 22 is cooled with water. Water is supplied to the hole in the plug installed at the bottom of adapter 6, and hot water is discharged from the hole in the plug installed at the top.

The valve is controlled by a multi-turn electric drive 43 mounted on a rack 27 through a threaded bushing 42. The force from the electric drive 43 is transmitted to the gate 7 through a composite spindle 22 and 23, connected to each other by a coupling 25 and installed pins 26 to prevent rotation of one part of the spindle relative to the other. The spindle 22 is connected to the gate 7 by means of a bracket 20 and pins 21, which are fixed with cotter pins 39.

The cover 4 has four holes for access to the internal cavity of the valve for inspection and assembly, which are plugged with blind flanges 44 through gaskets 45.

And also in the upper part of the cover 3 there is a hole 52 for connecting a safety valve.

The device works as follows.

When a signal is given to open or close the valve from the control panel or during emergency opening from a manual override, it is necessary to remove the locking pin 34 from the indicator post 28. Using an electric drive 43, torque is transmitted to the threaded bushing 42. Rotation of the threaded bushing in the spindle through a trapezoidal thread in spindle 23 is converted into translational motion of interconnected spindles 23 and 22. Spindle 22, in turn, is connected to the gate through the bracket 20 using the pins of the bracket 21, through which the force is transmitted to the gate, which moves in the direction of opening or closing, when the gate moves to the right the valve closes; when the gate moves to the left, the valve opens.

The advantages of a gate valve for a delayed coking unit are:

the possibility of installation on a delayed coking chamber due to the flat design of the body, which has smaller dimensions, a metal-to-metal seal in the valve assembly, as well as the presence of inlet and outlet openings for supplying steam to the internal cavity and removing condensate from the valve to prevent the formation of coke on parts,

ability to operate at high temperatures due to the use of heat-resistant materials for housing parts, fasteners and springs, as well as seals made of thermally expanded graphite,

ensuring tightness and the ability to work on coke unloading thanks to the presence of valve end position sensors for the coke unloading control system.

To cool the stuffing box assembly, it is possible to supply cooling water.

Heat-resistant materials are used for valve parts, in particular for body parts - 20Х5МЛ, 15Х5М, for fasteners - 25Х1МФ, for springs - Inconel Х-750.

Claims (3)

1. A gate valve containing a body, seats, a gate located inside the body and a gate covering the seat, a gate position sensor, a gate purge system, characterized in that the body is flat, the top and bottom covers are attached to the body on both sides, the top cover is closed by an installed flat cover, the lower cover is closed by an installed blind plug, the body has an upper movable and lower fixed seat, the lower seat has sealing rings, a clamping ring and a ring are attached to the upper seat, while the upper movable seat and ring are connected to the clamping ring by means of a bayonet connection using hooks , located on the rings, the movable upper seat and the ring are connected to each other using studs and nuts and form a stuffing box with sealing rings, and the clamping ring of the upper seat is stationary and pressed against the body, springs are installed in the holes between the movable seat and the clamping ring, the upper and The lower covers have holes in the upper part for supplying steam, and in the lower part there are openings for condensate removal; a casing, which is a flat box, is attached to the body from the side of the lower cover using a flange; from the side of the upper cover, a spindle is attached to the gate, designed to connection with the valve control element, an adapter is installed on the flat cover, on which the drive and indicator stands are installed, while on the indicator stand there is a valve position indicator in the form of an arrow and gate position sensors, at the junction of the spindle and indicator with the top cover of the housing there are gland units , consisting of rings, packing bushings, gland flanges, the working surfaces of the gate are nitrided. 2. The gate valve according to claim 1, characterized in that the cover has holes for inlet and outlet of cooling water. 3. The gate valve according to claim 1, characterized in that the rack has a locking rod connected to a guide sleeve, with a locking pin and position sensors.