RU2201537C1 - Fluid-motor pneumatic actuator - Google Patents

Abstract

FIELD: actuators for pipeline valves. SUBSTANCE: actuator has electropneumatic control unit connected to gas conduit for working medium supply and coupled through ducts with fluid-motor rotor whose shaft is kinematically coupled with working shaft; it also has device for limiting torque transferred by the latter and position detectors connected to electric input of mentioned control unit; gas conduit is designed for connection to main gas line; control unit is arranged for changing over main gas line under pressure, and fluid motor shaft is kinematically coupled with working shaft by means of multistep reduction unit incorporating intermediate shaft for mounting manual control means; torque limiting device is made in the form of two jaw half-clutches brought in mesh. EFFECT: enhanced reliability. 5 cl, 8 dwg

Description

 The invention relates to pneumatic automation and relates to a pneumatic actuator for valves in pipelines.

 The pneumatic drive can be used on pipeline fittings of oil and gas pipelines, in oil refineries and chemical enterprises.

 The drive is known from the prior art for a drive of shutoff and control valves of oil product pipelines, comprising an electric motor, a backup pneumatic motor connected to an autonomous source of working gas under pressure, a mechanical gearbox, an actuator position control device, and a control system [1].

 The backup pneumatic motor in the known drive is permanently connected to the motor shaft and rotates with it during operation of the electric motor. The rotor of a plate-type pneumatic engine has the ability to rotate under the action of a working gas from an autonomous source only in one direction. A pneumatic engine operates only when "oil mist" is supplied to the engine cavity.

 All this limits the technological capabilities of the engine and drive as a whole, complicates the maintenance process, reduces the reliability of the work.

 Known redundant drive shutoff and control valves of oil pipelines, containing an electric motor, a backup pneumatic engine connected to an autonomous source of working gas under pressure, a mechanical gearbox, a device for monitoring the position of the Executive body, the limiter of the transmitted moment and the drive control unit (BUP) [2].

 The pneumatic engine is made in the form of a single-sided rotation jet engine. To operate the pneumatic backup engine for emergency shutter closure, an autonomous source of working gas is used in the form of compressed gas cylinders or gas generators that have a limited resource.

 All this limits the technological capabilities of the drive; long-term operation of the drive from a pneumatic jet engine is not ensured. Bilateral action is not provided, i.e. to “open” and “close”, but only to “close” in the event of an emergency (for example, when a pipeline ruptures, etc.).

 Most gas and oil fields in the Far North, Kamchatka, and Sakhalin do not have a three-phase current supply voltage of 380 V. In these areas, it is impossible to use drives with three-phase current induction motors of 380 V.

 The basis of the present invention is the development of such a drive with a pneumatic jet engine for valves, pipelines, which would ensure long-term operation using the gas pressure of the main gas pipeline.

 The problem is solved in that in a drive with a pneumatic jet engine containing a mechanical gearbox, a travel switch mechanism, a torque limiting device and a drive control unit, according to the invention, the pneumatic jet engine is reversible (double-acting), and the input of the drive control unit is connected to the gas duct with main gas pipeline.

 The invention is illustrated by examples of specific performance and drawings.

 The essence of the invention lies in the fact that in a pneumatic drive with a jet engine containing an electro-pneumatic control unit (drive control unit) connected to the gas supply of the working medium and connected to the channels of the rotor of the jet engine, the shaft of which is kinematically connected to the working shaft, and also a limiting device the torque transmitted by the latter, and position sensors (the mechanism of the travel switch) associated with the electrical input of the said control unit, the gas duct is configured to connections to the main gas pipeline, the control unit is configured to switch under pressure of the main gas pipeline, and the jet engine shaft is kinematically connected to the working shaft using a multi-stage gearbox made with an intermediate shaft for installing the manual control means, while the torque limiting device is made in the form of two engaged cam halves.

Preferably, each half-coupling of the torque limiting device is made with cams having two angles of inclination of the working surfaces on both sides (not shown), selected from the condition of allowing the half-coupling to be freely rotated relative to each other by an angle of 30 ÷ 60 ^° , while the half-coupling mounted on the working shaft, spring-loaded in the direction of the other coupling half.

 In this case, the multi-stage gearbox is made in the form of a pinion shaft, made integral with the shaft of the jet engine, and five gears mounted on the auxiliary, intermediate and working shafts, on the first of which there is a gear put into engagement with the pinion shaft and gear introduced into meshing with one of the gears mounted on said countershaft, and the other gear mounted on the latter is engaged with the gear mounted on the working shaft, while the gear ratio is engaged shaft gear is 2,5 ÷ 5 and meshes with the gear mounted on the working shaft, is equal to 1.

 At the same time, the drive can be equipped with a worm gear, connected in series with the working shaft, and is configured to install a backup engine in the form of an electric motor, and the jet engine is made reversible.

 The device is illustrated by drawings, where figure 1 shows a General view of the drive, side view; figure 2 is the same, a top view; figure 3 is a kinematic diagram of a jet engine; figure 4 - connection diagram of a jet engine with a worm gear drive; figure 5 is an embodiment of a rotor of a jet engine; figure 6 - the second embodiment of the rotor of the jet engine; 7 is a diagram of a power (secondary) worm gear; on Fig - section aa in Fig.7.

 The pneumatic drive contains a jet engine 1 (Fig. 1), a gearbox 2, a drive control unit (BCU) 3 (Fig. 2).

In this composition, the actuator can be used on pipe fittings (valves) with a bore diameter D _at 200 ... 400 mm.

For valves with a bore diameter D _at 500 ... 1200 mm, the actuator is used with a secondary power reducer 4 (Fig. 1), which increases the torque.

 The jet engine comprises a rotor 5 (Fig. 3), the shaft of which is equipped with a gear ring connected to a cylindrical gear placed in the housing 6. A spring-loaded cam coupling 7 is mounted on the key shaft of the jet engine, which engages with the coupling half of the worm gear 8.

 The coupling half 7 (Fig. 4) can be made to move along the shaft 9 for disengagement with the coupling half 8. For this, the coupling 7 is provided with an annular collar in which grooves 10 are made, and a stopper 12 is installed in the holder 11. With the help of a rotary lever (not shown) the coupling half is retracted to the left position so that the stopper 12 passes into the groove 10, after which the shaft 9 with the coupling half 7 is rotated until the shoulder engages with the stopper 12. The shaft is rotated by a key through a window in the housing 6 in which the plug 13 is installed.

 When the rotor 5 and shaft 9 rotate, the coupling under the action of the spring 14 breaks off the stopper, moves along the key and engages with the coupling half 8.

 A stop 15 is installed at the end of the shaft 9. The coupling half 8 is mounted on the worm shaft 16 of the gearbox 2. The worm shaft 16 interacts with the worm wheel 17, which is mounted on the output shaft 18. The rotor 5 can be made in two versions (FIGS. 5 and 6) on which the nozzles 19 and 20 are mounted.

 The nozzles 19 by channels 21 are connected with the axial hole of the shaft on one side, and the nozzles 20 by channels 22 are connected with the axial hole of the shaft on its other side (Fig. 3). Axial shaft openings are divided among themselves.

 On the gearbox 23 (Fig. 4) of the drive there is a place for installing an electric motor 24 in case of a future appearance of a 380 V three-phase network on the pipelines.

 The mounting location is closed by a lid 25. In the housing 26 (Fig. 8) of the power (secondary) gearbox, a worm wheel 27 is installed on the bearings, which interacts with the worm 28 (Fig. 7). The worm 28 is installed in the housing with bearings 29.

 At the end of the shaft with a key 30 is mounted and attached to the flange of the housing 26 gear 2 (Fig.1) of the drive. The worm wheel 27 is mounted on the output shaft 31.

 The pneumatic drive operates as follows.

 On the control unit of the actuator 3 (figure 2) a signal of 220 V AC or 110 V DC is applied to the operation of one or another pneumatic valve. Gas from the main gas pipeline enters the jet engine 1.

 Gas through the axial hole of the rotor shaft 5 and, for example, channel 21 (Fig. 3), enters the nozzle 19. Expiring from the nozzle 19, the gas jet creates a reactive force. The rotor starts to rotate and drives the spur gear of the jet engine. Next, the rotation is transmitted to the shaft-worm 16 (figure 4), the worm wheel 17 and the output shaft 18.

 The output shaft 18 drives the worm 28 (Fig. 7). The rotation is transmitted to the worm wheel 27 (Fig. 8), which is mounted on the output shaft 31. The rotation of the output shaft 31 drives the closure of the pipe fittings.

 To rotate in the opposite direction, the signal is supplied to another pneumatic valve of the drive control unit. Pneumatic valves can be manually actuated by pressing the corresponding valve lever.

 From available sources of information, a device with similar features was not identified. The use of a pneumatic drive with a jet engine in the Far North, Kamchatka and Sakhalin in the absence of three-phase current networks with a voltage of 380 V will solve the problem of the energy crisis in these areas.

 The use of such a pneumatic actuator in comparison with the known ones provides the expansion of technological capabilities, increases reliability and simplifies the maintenance process.

 The drive design uses widely known and affordable materials. The manufacture of the drive is possible in conditions of mass production of a machine-building enterprise. It does not require special, unique mills and equipment.

 As part of the Sakhalin-2 project, prototypes of the drive were manufactured and tested, which were tested using the energy of compressed gas cylinders on the territory of the applicant enterprise.

 At the demonstration site of the Nurlino oil pumping station (Bashkiria), the drive was tested using gas from a compressor and using gas from a solid fuel gas generator.

 Tests have shown positive results.

Sources of information
1. The prospectus of the BIFFI company "Technical description and installation guide for multi-turn electric servo drives SGR / PN", Italy, 1994, p. 1-17.

 2. Certificate for utility model RU 3804, 09/05/96.

Claims (6)

 1. A pneumatic drive with a jet engine, comprising an electro-pneumatic control unit connected to a gas supply line for the working medium and connected to the channels of the rotor of the jet engine, the shaft of which is kinematically connected to the working shaft, as well as a device for limiting the torque transmitted by the latter, and position sensors associated with an electrical input of said control unit, characterized in that the gas duct is configured to be connected to a main gas pipeline, the control unit is made with possibly Tew switching pressure gas pipeline, and the jet shaft of the engine is kinematically connected to the working shaft by means of a multistage gear, countershaft configured to set the manual control means, wherein the torque limiting device is designed as two introduced into engagement claw coupling halves. 2. The drive according to claim 1, characterized in that each half-coupling of the torque limiting device is made with cams having two angles of inclination of the working surfaces on both sides, selected from the condition that the coupling halves can be freely rotated relative to each other by an angle of 30-60 ^o , wherein the coupling half mounted on the working shaft is spring loaded in the direction of the other coupling half.  3. The drive according to claim 1 or 2, characterized in that the multi-stage gearbox is made in the form of a gear shaft, made integral with the jet engine shaft, and five gears mounted on auxiliary, intermediate and working shafts, on the first of which a gear is installed, the gear engaged and the gear engaged with one of the gears mounted on said countershaft, and the other gear mounted on the latter gearing with the gear mounted on the working shaft, wherein datochnoe ratio meshes with the pinion shaft of 2.5-5 and in engagement with a pinion mounted on the operating shaft, is equal to 1.  4. The drive according to any one of paragraphs. 1-3, characterized in that it is equipped with a worm gear, connected in series with the working shaft.  5. The drive according to any one of paragraphs. 1-4, characterized in that it is configured to install a backup engine in the form of an electric motor.  6. The drive according to any one of paragraphs. 1-5, characterized in that the jet engine is made reversible.

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