A pneumatic-hydraulic tension compensation device and implementation method

Abstract

The present invention discloses a pneumatic-hydraulic tension compensation device and an implementation method, which includes a cylinder assembly formed by welding an energy storage cylinder, a hydraulic cylinder barrel, and left and right end covers. The central axis of the hydraulic cylinder barrel and the central axis of the upper half cylindrical barrel of the energy storage cylinder form a certain eccentricity in the working state position; a piston, a piston rod, an intermediate seat, and a right end cover are arranged inside the hydraulic cylinder barrel, and the hydraulic cylinder barrel is sequentially divided into an atmosphere area, a working area, and a sealed protection area from left to right by the piston and the intermediate seat. Hydraulic oil is filled inside and outside the hydraulic cylinder barrel, and an energy storage area is formed in the upper part of the energy storage cylinder, and high-pressure gas is filled inside as an energy storage medium. The sealing system of the present invention is composed of a tire-type piston seal ring, an I-shaped piston rod seal ring, and a sealing medium of high-pressure liquid introduced into the seal ring cavity. The concept of a sealed protection area is introduced, overcoming the problem of low-temperature load leakage commonly existing in existing compensation devices, and reliable sealing can be achieved at all temperature points of the environment.

Description

Technical Field

[0001] The present invention relates to the technical field of electrified railway power supply, and particularly to an automatic tension compensation device for the contact wire and the messenger wire of an electrified transportation track catenary. Background Art

[0002] Currently, the automatic compensation of the tension of the contact wire of an electrified transportation track with the change of the environmental temperature is mainly completed by using a counterweight. This method is inconvenient for installation and maintenance due to its large weight, not beautiful, especially when installing a counterweight in a tunnel, it is necessary to expand the cross-section of the tunnel, greatly increasing the workload, project cost, and construction period. For complex geological sections and bridges, it is even difficult to implement. Another is a spring compensation device, with a small number of foreign brands used. Although this device overcomes the disadvantage of large volume, it exposes the disadvantages of insufficient compensation accuracy and stability, and at the same time, it is heavy in weight and high in cost.

[0003] The third is the pneumatic tension compensation device and the pneumatic-hydraulic tension compensation device or the liquid-pneumatic or hydraulic tension compensation device that forms a patent. These compensation devices can be generally classified into the following types:

[0004] 1. Pneumatic tension compensation device, where the energy storage medium and the working medium are both gases. Although this type of compensation device has the advantages of being light, low in cost, and convenient for installation, the biggest problem is that the sealing cannot pass the test. Especially when the environmental temperature is low and the piston rod (extension rod) extends relatively long, and the compensation device is horizontally suspended, under the action of external forces such as wind force and gravity, the piston rod gets stuck and air leakage occurs;

[0005] 2. Pneumatic-hydraulic compensation device. This type of device also generally has the problem that when the environmental temperature is low, the piston rod (extension rod) extends too long, and the compensation device is horizontally suspended. Under the action of vertical external forces such as wind force and gravity, especially the wind vibration effect caused by the wind pulsation effect, the piston rod (extension rod) is suspended too long outside with poor guidance, resulting in intermittent twisting and jamming, destroying the tightness between the sealing ring and the sliding surface and causing leakage. At the same time, for the compensation device with a variable force mechanism or a hydraulic system control system, such as a liquid-gas or hydraulic compensation device, in addition to the above-mentioned disadvantages, there are also: too many links in the compensation device, inconvenient installation, poor compensation sensitivity, and low compensation accuracy. There is also a pneumatic-hydraulic compensation device that uses a liquid as a polymer elastomer. Since the working medium of this compensation device is a polymer elastomer solution, it has the characteristics of compressibility and viscoelasticity. The energy consumption due to temperature change is large (overcoming viscosity), and at the same time, the elastomer deforms to store energy. The thermal energy change of the gas in the compensation device cannot effectively compensate for the change caused by the temperature of the compensated wire. Therefore, this compensation device cannot achieve the compensation effect or has poor compensation accuracy. Due to the above deficiencies of the pneumatic, pneumatic-hydraulic (liquid-gas) or hydraulic tension compensation devices, the normal application of this type of compensation device has not been achieved. Summary of the Invention

[0006] The object of the present invention is to overcome the deficiencies of the above-mentioned compensation devices, and to provide a reliable pneumatic-hydraulic type automatic tension compensation device for realizing the tension of the electrified catenary wire, which can meet the requirements of compensation accuracy. While improving the compensation accuracy, it overcomes the common problem of low-temperature load leakage existing in the existing pneumatic, pneumatic-hydraulic (hydraulic-pneumatic) or hydraulic tension compensation devices.

[0007] The technical solution of the present invention is as follows:

[0008] A pneumatic-hydraulic type tension compensation device includes a cylinder assembly welded by an energy storage cylinder, a hydraulic cylinder barrel, and left and right end covers. The vertical cross-section of the energy storage cylinder is elliptical. The hydraulic cylinder barrel is inserted and welded at the bottom of the energy storage cylinder, so that the central axis of the hydraulic cylinder barrel and the central axis of the upper cylindrical barrel of the energy storage cylinder form a certain eccentricity e in the working state position. The compensation device is filled with two media, high-pressure gas and high-pressure hydraulic oil. Inside the hydraulic cylinder barrel, there are a piston, a piston rod, an intermediate seat and a right end cover. The hydraulic cylinder barrel is sequentially divided into an atmosphere area D, a working area G and a sealed protection area B from left to right by the piston and the intermediate seat. High-pressure hydraulic oil is filled inside and outside the hydraulic cylinder barrel, and is used as the working medium and the sealing medium in the working area G and the sealed protection area B respectively. An energy storage area C is formed in the upper part of the energy storage cylinder, and high-pressure gas is filled inside as the energy storage medium.

[0009] Further, a tire-shaped sealing ring is provided on the piston, and an I-shaped sealing ring is provided between the right end cover of the hydraulic cylinder barrel and the piston rod. The energy storage area, the working area and the sealed protection area are connected through a small hole a. The tire-shaped sealing ring is connected to the working area, and the I-shaped sealing ring is connected to the sealed protection area.

[0010] Furthermore, a support pressing ring with a small hole a is sleeved inside the I-shaped sealing ring. The I-shaped sealing ring is fixed and pressed by a pressing nut, and high-pressure hydraulic oil enters the I-shaped sealing ring through the small hole a.

[0011] Furthermore, a small hole b communicating with the tire-shaped sealing ring is provided on the right side of the piston, and high-pressure hydraulic oil enters the tire-shaped sealing ring through the small hole b.

[0012] Further, a valve for filling high-pressure gas or hydraulic oil into the energy storage cylinder is provided on the left end cover of the energy storage cylinder.

[0013] Further, the atmosphere area is connected to the atmosphere through a bent pipe. A brake plug is installed at the end of the bent pipe. A tire-shaped brake sealing ring is provided on the left side of the piston, and a through hole c communicating with the atmosphere area is provided on the brake sealing ring.

[0014] Further, a polytetrafluoroethylene guide sleeve is provided between the intermediate seat and the piston rod, and a functional sleeve of a certain length is provided between the intermediate seat and the right end cover to form a sealed protection area.

[0015] Another object of the present invention is to provide an implementation method of a pneumatic-hydraulic tension compensation device as described above. When designing the compensation device, the minimum length of the sealed protection area in the compensation device, that is, the minimum length of the functional sleeve, is first determined by the load simulation leakage test method;

[0016] After the compensation device is assembled and before leaving the factory for use, first fill it with 1 MPA of nitrogen, then fill a certain amount of hydraulic oil with a metering pump according to the calculation, and finally fill a certain pressure of nitrogen according to the tension of the compensated line segment. When inflating in the last link, install the compensation device on a special test bench with a tension sensor and a tension display. According to the ambient temperature during inflation, manually rotate the handwheel of the special test bench to pull the piston rod joint end of the compensation device to make the piston in the position corresponding to this temperature, and start inflating. When the tension display shows the required tension, the inflation is completed.

[0017] Further, the minimum value L of the length of the functional sleeve is designed by the load simulation leakage test method; the specific method is as follows:

[0018] (1) Test preparation

[0019] a) Install the un-inflated compensation device body on the tooling. By inserting the retaining pin into the jacks at different positions of the slider, adjust the piston rod to drive the piston to be at different positions in the hydraulic cylinder barrel, and straighten the wire rope. The jacks on the slider are equally spaced, and the spacing distance is 25 mm. The jacks are numbered 1, 2, 3, 4... from right to left in sequence;

[0020] b) Prepare counterweights. The weight of the counterweights is determined by calculating the wind force F value according to different specifications of the compensation device. When the compensation device is installed on the catenary for work, considering the influence of wind vibration caused by wind force pulsation, the F value is determined according to the compensation device specifications combined with the wind load W k Decide:

[0021] F = W k *D(*H1 + L1)

[0022] Wherein, H1 - the length of the device body, L1 - the extension of the piston rod, D - the distance between the upper and lower cylindrical generatrices of the body in the installed state of the compensation device; the wind load W k The algorithm refers to GB-50009-2001;

[0023] c) Setting the leakage rate of the helium detector: Set a maximum leakage rate on the helium detector. The maximum leakage rate is calculated based on the condition that the working pressure loss caused by leakage does not exceed 3% after the product has been used for 40 years (twice the product life). (When calculating, the gas volume at the piston position in the lowest temperature state of the product is used). If the leakage rate exceeds this value during product detection, it is considered unqualified and an alarm will be triggered.

[0024] (2) Test method

[0025] First step: Install the compensation device body on the tooling. Pull out the piston rod completely and then push it back. Insert the stop pin into the No. 1 jack at the rightmost side of the slider, so that the piston is at a position 5 mm to the left from the rightmost end. Then proceed as follows:

[0026] i) After screwing an M16 plug with a rubber gasket into the vent hole at the head of the bent pipe at the left end of the compensation device to block the hole, start vacuuming, and then fill it with helium. When the inflation pressure reaches 0.5 - 1 MPA, remove the plug and continue inflating to reach the required rated pressure.

[0027] ii) Put the inflated compensation device together with the tooling into the helium detection equipment box.

[0028] iii) Press the pre-calculated and prepared counterweight on the compensation device.

[0029] iv) Vacuum the helium detection equipment box and detect the leakage rate. If an alarm is triggered, proceed to the second step.

[0030] Second step: Remove the counterweight, take out the compensation device and the tooling from the helium detection equipment box, put them back to the original position, then connect the inflation nozzle connected to the nitrogen tank to the bent pipe head of the compensation device, and fill the compensation device with nitrogen through the bent pipe head. Apply pressure to make the piston overcome the helium resistance. When the stop pin becomes loose, pull it out and insert it into the adjacent No. 2 jack on the left side. Release the pressure to make the piston move slowly. After the stop pin takes effect, close the inflation valve and remove the inflation nozzle. Then repeat the above steps ii), iii), and iv).

[0031] Third step: Similarly, perform the above operations for the No. 3 hole, No. 4 hole,..., until no alarm is triggered. Record the sequence numbers of the holes without alarm, and then the minimum L value of the sealing protection area, that is, the functional sleeve, can be determined.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] (1) In the present invention, there is an offset distance e between the centers of the hydraulic cylinder barrel and the upper cylindrical barrel of the energy storage cylinder. High-pressure hydraulic oil is filled inside and outside the hydraulic cylinder barrel. An energy storage area is formed in the upper part of the energy storage cylinder, and high-pressure gas is filled inside as the energy storage medium. Due to the different densities of gas and hydraulic oil, and the incompressibility of oil, the oil and gas naturally separate. The gas is above, and the heavier oil is below the inside and outside of the hydraulic cylinder barrel, reducing links such as air bags. The structure is simple, the compensation is sensitive and reliable, and the compensation accuracy is improved.

[0034] (2) In the present invention, the entire structure of the compensation device forms four functional areas: area D (communicating with the atmosphere), area G (the working area where the piston moves inside the cylinder barrel), area C (the energy storage area), and area B (the sealed protection area); the function of introducing a broken wire brake is set in area D to prevent the compensation device from being damaged due to abnormal wire breakage; the concept of the sealed protection area B is introduced in the functional area. The addition of this area enables the compensation device, especially when the piston rod extends a large amount under low-temperature conditions during use, not to cause wind vibration due to natural external forces, especially wind pulsation, resulting in intermittent deformation and jamming of the piston rod and damaging the normal seal of the sealing system. The purpose of the sealed protection area is to ensure reliable sealing of the device at all temperature points in the environment during use, overcoming the common problem of low-temperature load leakage in existing compensation devices.

[0035] (3) In the present invention, the dynamic seal adopts a systematic seal structure design. The entire sealing system consists of a tire-shaped piston seal ring, an I-shaped piston rod seal ring, and a sealing medium of high-pressure liquid introduced into the working area, the sealed protection area, and the seal ring cavity. The sealing mechanism is to use the working medium of high-pressure liquid as the sealing medium and introduce it into the inner cavities of the tire-shaped seal ring and the I-shaped seal ring, so that the seal ring tightly presses the moving contact surface for effective sealing. Description of the Drawings

[0036] Figure 1 is a schematic cross-sectional structure view of the gas-hydraulic tension compensation device of the present invention;

[0037] Figure 2 is a schematic installation structure view of the compensation device in the load simulation leakage test;

[0038] Figure 3 is Figure 2 the C-C view of

[0039] Figure 4 is Figure 2 the B view of

[0040] In the figure, there are energy storage cylinder 1, hydraulic cylinder barrel 2, tire-shaped sealing ring 3, piston 4, intermediate seat 5, guide sleeve 6, compression nut 7, functional sleeve 8, support compression ring 9, I-shaped sealing ring 10, right end cover 11, left end cover 12, piston rod 13, brake sealing ring 14, brake plug 15, valve 16, stop pin 101, slider 102, steel wire rope 103, jack hole 104, tooling 201, counterweight 202, helium detection equipment box 203; atmosphere area D area, working area G area, sealed protection area B area, energy storage area C area. Specific embodiments

[0041] Next, in combination with the accompanying drawings and embodiments of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments.

[0042] As Figure 1 shown, a pneumatic-hydraulic tension compensation device includes a cylinder assembly welded by an energy storage cylinder 1, a hydraulic cylinder barrel 2, and left and right end covers. The vertical cross-section of the energy storage cylinder 1 is oval. The hydraulic cylinder barrel 2 is inserted and welded at the bottom of the energy storage cylinder 1, so that the central axis of the hydraulic cylinder barrel 2 and the central axis of the upper cylindrical barrel of the energy storage cylinder 1 form a certain eccentricity e in the working state position. The compensation device is filled with two media, high-pressure gas and hydraulic oil; inside the hydraulic cylinder barrel 2, there are a piston 4, a piston rod 13, an intermediate seat 5, and a right end cover 11. The hydraulic cylinder barrel 2 is sequentially divided into an atmosphere area D, a working area G, and a sealed protection area B from left to right by the piston 4 and the intermediate seat 5. Hydraulic oil is filled inside and outside the hydraulic cylinder barrel 2, and is used as the working medium and the sealing medium in the working area G and the sealed protection area B respectively. An energy storage area C is formed in the upper part of the energy storage cylinder 1, and high-pressure gas is filled inside as the energy storage medium.

[0043] As Figure 1 shown, a tire-shaped sealing ring 3 is provided on the piston 4, and an I-shaped sealing ring 10 is provided between the right end cover 11 of the hydraulic cylinder barrel 2 and the piston rod 13. The energy storage area C, the working area G, and the sealed protection area B are connected through a small hole a. The tire-shaped sealing ring 3 is connected to the working area G, and the I-shaped sealing ring 10 is connected to the sealed protection area B.

[0044] The G area, the C area, and the B area are connected through the small hole a, so that the filled high-pressure gas pushes the high-pressure hydraulic oil to penetrate into the G area, the C area, the B area, the tire-shaped sealing ring 3, and the I-shaped sealing ring 10. In a specific embodiment, the high-pressure gas uses high-purity nitrogen, and the inflation pressure is determined according to the rated tension of the wire to be compensated. The high-pressure hydraulic oil uses high and low temperature resistant anti-wear oil.

[0045] As Figure 1As shown, a support pressing ring 9 with small holes is sleeved inside the I-shaped sealing ring 10. The I-shaped sealing ring 10 is fixed and pressed by a pressing nut 7. High-pressure hydraulic oil enters the I-shaped sealing ring 10 through the small hole a on the right end cover 11.

[0046] In this embodiment, high-pressure hydraulic oil enters the I-shaped sealing ring 10 through the small hole a to form a piston rod dynamic sealing structure.

[0047] As Figure 1 shown, a small hole b communicating with the tire-shaped sealing ring 3 is provided on the right side of the piston 4. High-pressure hydraulic oil enters the tire-shaped sealing ring 3 through the small hole b.

[0048] In this embodiment, high-pressure hydraulic oil enters the tire-shaped sealing ring 3 through the small hole b at the piston end to form a piston dynamic sealing structure.

[0049] As Figure 1 shown, a valve 16 for filling high-pressure gas or hydraulic oil into the energy storage cylinder 1 is provided on the left end cover 12 of the energy storage cylinder 1.

[0050] In the present invention, there is an offset distance e between the centers of the upper cylindrical parts of the hydraulic cylinder barrel 2 and the energy storage cylinder 1. The left end cover 12 of the energy storage cylinder is provided with a valve 16 for inflating or filling liquid into the energy storage cylinder 1, so that two media (high-pressure gas, hydraulic oil) are filled in the compensation device. First, a certain amount of high-quality engineering hydraulic oil is filled. The filling amount is such that when the piston rod is fully retracted, the hydraulic cylinder is just buried in the hydraulic oil. Finally, high-purity nitrogen gas at a certain pressure is filled. During operation, the large weight and incompressibility of the oil cause high-pressure gas, i.e., the energy storage medium, to be formed in the upper part of the energy storage cylinder of the compensation device, and high-pressure hydraulic oil, i.e., the working medium and the sealing medium, to be formed inside and outside the hydraulic cylinder barrel; the links such as air bags are reduced, the structure is simple, and the compensation is sensitive and reliable.

[0051] In the present invention, the entire structure of the compensation device forms four functional regions: region D (communicating with the atmosphere), region G (the working region for the piston movement inside the cylinder barrel), region C (the energy storage region), and region B (the sealing protection region). The concept of the sealing protection region is introduced in the functional regions. The addition of this region enables the compensation device, especially when the piston rod extends a large amount under low-temperature conditions during use, not to be affected by natural external forces, especially wind pulsation, resulting in wind vibration, which may cause intermittent deformation and jamming of the piston rod and damage the normal sealing of the sealing system. The purpose of the sealing protection region is to ensure reliable sealing at all temperature points in the environment during the use of the device.

[0052] In the present invention, a static seal is formed between the right end cover 11 and the inner diameter of the hydraulic cylinder barrel 2 (sealing connection can be achieved through an O-ring), and a systematic seal structure design is adopted for the dynamic seal. The entire seal system consists of a tire-shaped piston seal ring 3, an I-shaped piston rod seal ring 10, and a sealing medium that introduces high-pressure liquid into the working area, the seal protection area, and the seal ring cavity. The sealing mechanism is to use the working medium of high-pressure liquid as the sealing medium and introduce it into the inner cavities of the tire-shaped seal ring and the I-shaped seal ring, so that the seal ring tightly presses against the moving contact surface to achieve effective sealing.

[0053] As Figure 1 shown, the atmosphere area D is connected to the atmosphere through a bent pipe, a brake plug 15 is installed at the end of the bent pipe, and a tire-shaped brake seal ring 14 is provided on the left side of the piston 4. A through hole c communicating with the atmosphere area is provided on the brake seal ring 14.

[0054] Principle of wire breakage braking: When an abnormal wire break occurs, the high-pressure liquid pushes the piston 4 to drive the piston rod 13 to quickly retract. The air pressure inside the D area rises sharply due to the damping effect of the brake plug 15, causing the seal ring to expand and play a sealing role. In this way, the air pressure in the D area increases sharply, the piston is blocked and its speed slows down automatically. The reduction of the piston's backward speed causes the pressure in the D area to decrease, the piston's backward movement accelerates again, the damping increases, and the piston's speed slows down again. This cycle repeats, causing the piston to slowly retract, achieving a braking effect and preventing the compensation device from being damaged due to abnormal wire breakage.

[0055] As Figure 1 shown, a polytetrafluoroethylene guide sleeve 6 is provided between the intermediate seat 5 and the piston rod 13, and a functional sleeve 8 with a certain length is provided between the intermediate seat 5 and the right end cover 11 to form a seal protection area.

[0056] As Figures 2 - 4 shown, an implementation method of a pneumatic-hydraulic tension compensation device. When designing the compensation device, the minimum length of the seal protection area in the compensation device, that is, the minimum length of the functional sleeve, is first determined through a load simulation leakage test method;

[0057] After the compensation device is assembled and before leaving the factory for use, first fill it with 1 MPA of nitrogen, then fill a certain amount of hydraulic oil with a metering pump according to the calculation, and finally fill nitrogen with a certain pressure according to the tension of the compensated line segment. When inflating in the above last link, install the compensation device on a special test bench with a tension sensor and a tension display. According to the ambient temperature during inflation, manually rotate the handwheel of the special test bench to pull the piston rod joint end of the compensation device to make the piston in the position corresponding to this temperature, and start inflating. When the tension display shows the required tension, the inflation is completed.

[0058] The design of the minimum length L of the functional sleeve is obtained through a load simulation leakage test method; the specific method is as follows:

[0059] (1) Test preparation

[0060] a) As shown Figure 2 , install the non-inflated compensator body on the tooling 201. Adjust the piston rod 13 to drive the piston 4 to different positions in the hydraulic cylinder barrel 2 by inserting the stop pin 101 into the jacks 104 at different positions of the slider 102, and straighten the wire rope 103. The jacks 104 on the slider 102 are equally spaced, and the spacing distance is 25 mm. The jacks 104 are numbered 1, 2, 3, 4... from right to left in sequence;

[0061] b) Prepare the counterweight 202. The weight of the counterweight 202 is determined by calculating the wind force F value according to different specifications of the compensator. When the compensator is installed on the catenary and working, consider the influence of wind vibration caused by wind pulsation. The F value is determined according to the compensator specification combined with the wind load W k as follows:

[0062] F = W k *D(*H1 + L1)

[0063] where, H1 - length of the device body, L1 - extension of the piston rod, D - distance between the upper and lower cylindrical generatrices of the compensator in the installed state; the wind load W k algorithm refers to GB - 50009 - 2001;

[0064] Specifically, the wind load W k = Bz * Us * Uz * W0; Bz - wind vibration coefficient at height Z, take Z = 5 m, Bz = 1.09 * correction factor (considering safety value 1.26) = 1.37; Us - wind load shape coefficient, the compensator is a cylinder with a circular arc transition on the side windward surface, take the value 1; Uz - wind pressure height change coefficient, take the value 1 for hilly and field areas (5 m height), take the value 1.19 (5 m height) for sandy area, seaside, and lakeside areas. Here, take the average value of the two as 1.1; W0 - basic wind pressure, look up the table and take the value 0.52 KN / M2, then: Wk = 1.37 * 1 * 1.1 * 0.52 KN / M2 = 0.784 KN / M2;

[0065] If the windward surface of the compensator is vertically affected by wind force on the side, then F = 0.784 * D(*H1 + L1) (KN); D - distance between the upper and lower cylindrical generatrices of the compensator in the installed state (unit, m), H1 - length of the device body (m), L1 - extension of the piston rod, take 0.7H1, then F = 1.333D * H1. For different specifications of compensators, D and H1 are fixed values, so the counterweight is weighted according to different specifications according to the F value.

[0066] C) Setting the leakage rate of the helium detector: Set the maximum leakage rate on the helium detector. If the leakage rate exceeds this value during product detection, it is considered unqualified and an alarm is issued.

[0067] Specifically, the service life of the compensation device is 20 years. For safety, multiply by a safety factor of 2, that is, calculate according to a 40-year life. The compensation accuracy for losses caused by leakage is 3%. When calculating the leakage rate for different specifications of the compensation device, calculate according to the gas volume at the piston position in the lowest temperature state of the product, that is, the pressure loss caused by leakage in 40 years at this volume is 3%, and the leakage rate can be calculated. Set this value as the maximum leakage rate on the helium detector. If the leakage rate exceeds this value during product detection, it is considered unqualified and an alarm is issued.

[0068] (2) Test method

[0069] First step: Install the compensation device body on the tooling 201. Pull out the piston rod 13 completely and then retract it. Insert the stop pin 101 into the No. 1 jack 104 at the rightmost side of the slider 102 so that the piston 4 is at the position where it retracts 5 mm from the rightmost end. Then proceed in the following order:

[0070] 1) After screwing an M16 plug with a rubber gasket into the ventilation port at the head of the bent pipe at the left end of the compensation device to block the hole, start vacuuming, and then fill with helium. When the inflation pressure reaches 0.5 - 1 MPA, remove the plug and continue inflating to reach the required rated pressure;

[0071] 2) Put the inflated compensation device together with the tooling into the helium detection equipment box 203;

[0072] 3) Press the pre-calculated and prepared counterweight 202 on the compensation device;

[0073] 4) Vacuum the helium detection equipment box 203 and detect the leakage rate. If an alarm is issued, proceed to the second step;

[0074] Second step: Remove the counterweight, take out the compensation device and the tooling from the helium detection box, put them back to the original position, then connect the inflation nozzle connected to the nitrogen tank to the bent pipe head of the compensation device, fill with nitrogen through the bent pipe head of the compensation device, pressurize to make the piston overcome the helium resistance. When the stop pin 101 becomes loose, pull it out and insert it into the adjacent No. 2 jack on the left. Inflate and decompress to make the piston move slowly. After the stop pin 101 takes effect, close the inflation valve and remove the inflation nozzle. Then repeat the above 2), 3), and 4) contents;

[0075] Third step: Similarly, perform the above operations for the No. 3 hole, No. 4 hole,..., until no alarm is issued. Record the sequence number of the hole without alarm, then the maximum stroke of the compensation device can be determined, and then the minimum L value of the functional sleeve can be determined.

[0076] The above are only the preferred specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, making equivalent substitutions or changes, shall be covered by the protection scope of the present invention.

Claims

1. A pneumohydraulic tension compensation device, comprising a cylinder assembly formed by welding a energy storage cylinder (1), a hydraulic cylinder barrel (2), and left and right end covers, characterized in that, the vertical cross-section of the energy storage cylinder (1) is elliptical, the hydraulic cylinder barrel (2) is inserted and welded at the bottom position of the energy storage cylinder (1), so that the central axis of the hydraulic cylinder barrel (2) and the central axis of the upper cylindrical barrel of the energy storage cylinder (1) form a certain eccentricity e in the working state position, and the compensation device is filled with two media of high-pressure gas and hydraulic oil; a piston (4), a piston rod (13), an intermediate seat (5) and a right end cover (11) are arranged inside the hydraulic cylinder barrel (2), and the hydraulic cylinder barrel (2) is sequentially divided into an atmosphere area, a working area and a sealed protection area from left to right by the piston (4) and the intermediate seat (5). Hydraulic oil is filled inside and outside the hydraulic cylinder barrel (2), and is used as a working medium and a sealing medium in the working area and the sealed protection area respectively. An energy storage area is formed in the upper part of the energy storage cylinder (1), and high-pressure gas is filled inside as an energy storage medium; a tire-shaped sealing ring (3) is provided on the piston (4), an I-shaped sealing ring (10) is provided between the right end cover (11) of the hydraulic cylinder barrel (2) and the piston rod (13), the energy storage area, the working area and the sealed protection area are connected through a small hole a, and the tire-shaped sealing ring (3) is connected to the working area, and the I-shaped sealing ring (10) is connected to the sealed protection area; a support pressing ring (9) with small holes is sleeved inside the I-shaped sealing ring (10), the I-shaped sealing ring (10) is fixed and pressed by a pressing nut (7), and high-pressure hydraulic oil enters the I-shaped sealing ring (10) through the small hole a on the right end cover (11); a small hole b communicating with the tire-shaped sealing ring (3) is provided on the right side of the piston (4), and high-pressure hydraulic oil enters the tire-shaped sealing ring (3) through the small hole b.

2. A pneumohydraulic tension compensation device according to claim 1, characterized in that, a valve (16) for filling high-pressure gas or hydraulic oil into the energy storage cylinder (1) is provided on the left end cover (12) of the energy storage cylinder (1).

3. A pneumohydraulic tension compensation device according to claim 1, characterized in that, the atmosphere area is communicated with the atmosphere through a bent pipe, a brake plug (15) is installed at the end of the bent pipe, a tire-shaped brake sealing ring (14) is provided on the left side of the piston (4), and a through hole c communicating with the atmosphere area is provided on the brake sealing ring (14).

4. A pneumohydraulic tension compensation device according to claim 1, characterized in that, a polytetrafluoroethylene guide sleeve (6) is provided between the intermediate seat (5) and the piston rod (13), and a functional sleeve (8) of a certain length is provided between the intermediate seat (5) and the right end cover (11) to form a sealed protection area.

5. An implementation method of a pneumohydraulic tension compensation device according to claim 4, characterized in that, When designing the compensation device, the minimum length of the sealed protection area in the compensation device, that is, the minimum length of the functional sleeve, is first determined by the load simulation leakage test method; After the compensation device is assembled and before leaving the factory for use, first fill it with nitrogen at 1 MPA, then fill a certain amount of hydraulic oil with a metering pump according to the calculation, and finally fill nitrogen at a certain pressure according to the tension of the compensated line segment. When inflating in the last link, install the compensation device on a special test bench with a tension sensor and a tension display. According to the ambient temperature during inflation, manually rotate the handwheel of the special test bench to pull the piston rod joint end of the compensation device to make the piston in the position corresponding to this temperature, and start inflating. When the tension display shows the required tension, the inflation is completed.

6. The implementation method of a pneumatic-hydraulic tension compensation device according to claim 5, characterized in that, the design of the minimum length L of the functional sleeve is obtained through the load simulation leakage test method; the specific method is as follows: (1)Test preparation a) Install the un-inflated compensation device body on the tooling. By inserting the stop pin into the jacks at different positions of the slider, adjust the piston rod to drive the piston to different positions in the hydraulic cylinder barrel, and straighten the wire rope. The jacks on the slider are equally spaced, and the spacing distance is 25 mm. The jacks are numbered 1, 2, 3, 4... from right to left in sequence; b) Prepare counterweights, the weight of which is determined by calculating the wind force F value according to different specifications of the compensation device. When the compensation device is installed and working on the catenary, the influence of wind vibration caused by wind pulsation is considered, and the F value is determined in combination with the wind load W according to the specifications of the compensation device k decide: F = W k *D(*H1 + L1) Among them, H1 - the length of the device body, L1 - the extension of the piston rod, D - the distance between the upper and lower cylindrical generatrices of the body in the installation state of the compensation device; wind load W k The algorithm refers to GB-50009-2001; c) Setting the helium detection machine leakage rate: Set the maximum leakage rate on the helium detection machine. When the leakage rate exceeds this value during product detection, it is considered unqualified and an alarm is given; (2)Test method The first step: Install the compensation device body on the tooling, fully pull out the piston rod and then retract it. Insert the stop pin into the No. 1 jack on the rightmost side of the slider to make the piston in the position where it retracts 5 mm from the rightmost end, and then proceed in the following order: i) Screw an M16 plug into the ventilation port at the head of the elbow pipe at the left end of the compensation device, and then fill it with helium; evacuate before inflation, then inflate. When the inflation pressure reaches 0.5 - 1 MPA, remove the plug and continue inflating to reach the required rated pressure; ii) Put the inflated compensation device together with the tooling into the helium detection equipment box; iii) Press the pre-calculated and prepared counterweight blocks on the compensation device; iv) Evacuate the helium detection equipment box and detect the leakage rate. If an alarm occurs, proceed to the second step; The second step: Remove the counterweight blocks, take out the compensation device and the tooling from the helium detection machine box, put them back to the original position, then connect the inflation nozzle connected to the nitrogen tank to the elbow pipe head of the compensation device, and fill nitrogen through the elbow pipe head of the compensation device. Pressurize to make the piston overcome the helium resistance. When the stop pin becomes loose, pull it out and insert it into the adjacent No. 2 jack on the left. Inflate and decompress to make the piston move slowly. After the stop pin takes effect, close the inflation valve and remove the inflation nozzle, and then repeat the above ii), iii), iv) contents; The third step: Similarly, detect the No. 3 hole, No. 4 hole... according to the operation in the second step above until no alarm occurs. Record the sequence number of the hole without alarm, and determine the minimum length of the sealed protection area in the compensation device, and then the minimum L value of the functional sleeve can be determined.

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