Welded blind hole cylinder low-pressure air tightness test device

Abstract

The utility model relates to a welded blind hole cylinder low-pressure air tightness test device, which comprises a pressure gauge joint, a bent pipe, a gas stop valve joint, a DN quick-change joint, a blanking cap, a U-shaped pin, an O-shaped ring and a rubber sealing gasket, and is fixedly connected with the head of a part through the blanking cap, and the DN quick-change joint is welded on the other end face of the blanking cap. A U-shaped pin is fixedly connected with a gas stop valve connector, the gas stop valve connector is connected with a disc handle external-thread single-nozzle valve, the disc handle external-thread single-nozzle valve is connected with an air compressor, and compressed air is introduced into the disc handle external-thread single-nozzle valve. The bent pipe is welded to the position, symmetrical to the DN quick-change connector, of the blanking cap, the bent pipe is welded to a pressure gauge connector and connected with a gas pressure gauge, gas is filled into an inner cavity of the barrel, when the pressure meets the requirement, the gas is cut off and subjected to pressure maintaining through the disc handle external-thread single-nozzle valve, liquid is smeared on a welding bead to check whether bubbles exist or not, the welding performance is verified, the technology is simple, and the machining cost is low. And the low-pressure air tightness test requirements of the welded blind hole cylinder can be effectively met.

Description

Technical Field

[0001] The utility model belongs to the field of mechanical processing technology, and particularly relates to a low-pressure air tightness test device for a welded blind hole cylinder. The device designs the size of the connection part according to the appearance characteristics of the part, adopts a rubber sealing pad for end face sealing, fills the part cavity with gas, cuts off the gas from entering after reaching the test pressure, maintains the pressure, and checks whether the weld is leaking. Background Art

[0002] At present, there is often a kind of blind hole cylinder that is welded together, which is divided into a head, a body, and a tail. The three parts are assembled together by welding, and low-pressure welding performance and sealing verification are required. In order to meet the welding sealing performance inspection, it is necessary to design a simple sealing test device based on the head characteristics of the parts to conduct welding performance inspection. Utility Model Content

[0003] The utility model aims to overcome the deficiencies in the prior art and provide a welding type blind hole cylinder low-pressure air tightness test device which is simple to manufacture, convenient to operate, economical and practical.

[0004] The technical solution of the utility model is achieved as follows: a welded blind hole cylinder low-pressure air tightness test device, including a plugging cover connected and fixed to the head of the cylinder through a rubber sealing gasket, and two through holes opened on the plugging cover, characterized in that: a bend is welded at the center of one through hole of the plugging cover, a pressure gauge joint connected to the bend is welded at the head of the bend, and a gas pressure gauge is installed on the pressure gauge joint; a DN quick-change joint is welded at the center of the other through hole of the plugging cover, the DN quick-change joint is connected and fixed to the gas stop valve joint through a U-shaped pin and an O-ring, the gas stop valve joint is connected to the disc handle external thread single nozzle valve through a thread, and then connected to the air compressor to access the gas.

[0005] A rubber sealing groove is opened on the end face of the plugging cover, and the rubber sealing gasket is installed in the rubber sealing groove. After the plugging cover is connected to the head of the cylinder, a gap of 0.5 to 1 mm is set between the head of the cylinder and the end face of the plugging cover. After the rubber sealing gasket is installed in the rubber sealing groove on the plugging cover, the sealing gasket is 0.5 to 1 mm higher than the end face of the sealing groove; after the plugging cover is connected and fixed to the head of the cylinder, there should be a gap of 0.5 to 1 mm between the head of the cylinder and the end face of the plugging cover.

[0006] A through hole is drilled in the center of the DN quick-change connector. The through hole of the DN quick-change connector and the gas shut-off valve connector are matched with clearances of H9 / f7 and H11 / d11 respectively. O-ring sealing grooves and U-shaped pin installation grooves are processed on the DN quick-change connector. The DN quick-change connector and the gas shut-off valve connector are assembled together and fixed with a U-shaped pin.

[0007] A through hole φd4 is opened in the center of the gas stop valve joint. One end is clearance-matched with the DN quick-change joint, and the other end is threadedly connected to the disc handle external thread single nozzle valve. The hole diameter φd4 is equal to the inner hole size of the disc handle external thread single nozzle valve. Raw tape is wrapped around the threads of the disc handle external thread single nozzle valve to ensure the sealing of the threaded connection.

[0008] The elbow is a 20# oil pipe fitting that needs to be heated and folded into a spiral shape.

[0009] The positive effects of the technical solution of the utility model are as follows:

[0010] The utility model discloses a welding type blind hole cylinder low pressure air tightness test device, except the elbow is made of the common 20# oil pipe, the other parts can be made of common materials such as 45, 27SiMn, etc., and the quenching and tempering treatment is HB240-280. The parts of this device are easy to obtain, the manufacturing process is simple, the processing cost is low, and the requirements of the welding type blind hole cylinder low pressure air tightness test can be effectively met. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a schematic diagram of the connection between the blind hole cylinder and the test device of the utility model.

[0012] Figure 2 The utility model is an assembly diagram of a welded blind hole cylinder low-pressure air tightness test device.

[0013] Figure 3 The utility model is a front cross-sectional view of a plugging cover of a welded blind hole cylinder low-pressure air tightness testing device.

[0014] Figure 4 The utility model is a front cross-sectional view of a pressure gauge joint of a welded blind hole cylinder low-pressure air tightness test device.

[0015] Figure 5 The utility model is a front cross-sectional view of a gas stop valve joint of a welded blind hole cylinder low-pressure air tightness test device.

[0016] Figure 6 The utility model is a cross-sectional view of a gas stop valve joint of a welded blind hole cylinder low-pressure air tightness test device.

[0017] Figure 7 The utility model is a left view of a DN quick-change joint of a welded blind hole cylinder low-pressure air tightness test device.

[0018] Figure 8 The utility model is a front view of a bent pipe of a welded blind hole cylinder low-pressure air tightness test device.

[0019] Fig. 9The utility model is a left view of a bend pipe of a welded blind hole cylinder low-pressure air tightness test device.

[0020] Fig.10 The utility model is a schematic structural diagram of a U-shaped pin of a welded blind hole cylinder low-pressure air tightness test device.

[0021] 1. Blind hole cylinder parts; 2. Sealing rubber plate; 3. Low-pressure air tightness test device; 4. DN quick-change connector; 5. U-shaped pin; 6. O-ring; 7. Gas stop valve connector; 8. Pressure gauge connector; 9. Elbow; 10. Plug cover. DETAILED DESCRIPTION

[0022] As shown in the figure, a welded blind hole cylinder low-pressure air tightness test device includes a pressure gauge connector 8, an elbow 9, a gas stop valve connector 7, a DN quick-change connector 4, a plugging cover 10, a U-shaped pin 5, an O-ring 6, and a rubber sealing gasket 2. Specifically, it is a welded blind hole cylinder low-pressure air tightness test device, comprising a plugging cover 10 connected and fixed to the head 11 of the cylinder 1 through a rubber sealing gasket 2, and two through holes opened on the plugging cover 10, characterized in that: a bend pipe 9 is welded at the center of a through hole of the plugging cover 10, and the tail of the bend pipe is connected to the through hole; a pressure gauge connector 8 connected to the bend pipe 9 is welded at the head of the bend pipe 9, and a gas pressure gauge is installed on the pressure gauge connector 8; a DN quick-change connector 4 is welded at the center of the other through hole of the plugging cover 10, and the center hole of the DN quick-change connector 4 is connected to the center hole of the above-mentioned through hole, the DN quick-change connector 4 is connected and fixed to the gas stop valve connector 7 through a U-shaped pin 5 and an O-ring 6, and the gas stop valve connector 7 is connected to the disc handle external thread single nozzle valve through a thread, and then connected to the air compressor to access the gas.

[0023] This device is connected and fixed to the head 11 of the cylinder 1 through a plug cover 10. A DN quick-change connector 4 is welded on the other end face of the plug cover 10, and is connected and fixed to the gas stop valve connector 7 through a U-shaped pin 5. The gas stop valve connector 7 is connected to a disc handle external thread single nozzle valve, and the disc handle external thread single nozzle valve is connected to an air compressor to introduce compressed air; an elbow 9 is welded to the plug cover 10 at a symmetrical position with the DN quick-change connector 4, and the elbow 9 is welded to the pressure gauge connector 8, and the pressure gauge connector 8 is connected to the gas pressure gauge. The inner cavity of the cylinder is filled with gas, and the pressure gauge displays the pressure in the cavity. When the pressure reaches the requirement, the gas is cut off through the disc handle external thread single nozzle valve to maintain the pressure, and then liquid is applied to the weld to check for bubbles, thereby verifying the welding performance.

[0024] A rubber sealing groove is opened on the end face of the plugging cover 10, and the rubber sealing gasket 2 is installed in the rubber sealing groove. After the plugging cover 10 is connected to the head 11 of the cylinder, a gap of 0.5 to 1 mm is set between the head 11 of the cylinder and the end face of the plugging cover 10. After the rubber sealing gasket 2 is installed in the sealing groove of the plugging cover 10, the sealing gasket is 0.5 to 1 mm higher than the end face of the sealing groove; after the plugging cover 10 is connected and fixed to the head 11 of the cylinder, there should be a gap of 0.5 to 1 mm between the head 11 of the cylinder and the end face of the plugging cover 10.

[0025] A through hole φd2 is drilled in the center of the DN quick-change connector 4. The inner hole sizes φD2 and φD3 of the DN quick-change connector 4 are matched with the gas shut-off valve connector 7 according to the clearances of H9 / f7 and H11 / d11 respectively. An O-ring sealing groove and a U-shaped pin installation groove are processed on the DN quick-change connector 4. The DN quick-change connector 4 and the gas shut-off valve connector 7 are assembled together and fixed with a U-shaped pin 5.

[0026] A through hole φd4 is provided at the center of the gas shut-off valve connector 7, one end of which is clearance-matched with the DN quick-change connector 4, and the other end is threadedly connected to the disc handle external thread single nozzle valve. The aperture φd4 is equal to the inner hole size of the disc handle external thread single nozzle valve, and raw tape is wrapped around the threads of the disc handle external thread single nozzle valve to ensure the sealing of the threaded connection.

[0027] The elbow 9 is a 20# oil pipe fitting, which needs to be heated and bent into a spiral shape.

[0028] Match the characteristics of the plugging cover and the cylinder head, determine the connection method between the plugging cover and the cylinder head: screws, threads, clamps, etc., use the simplest and fastest method to connect and fix the plugging cover to the cylinder, and determine the sealing form between the plugging cover and the cylinder head: outer circle seal or end face seal.

[0029] Now, we will take the example of positioning the stopper of cylinder 1, fixing with screws, threading the inner hole of cylinder 1, milling a groove on the end face of the cylinder, and sealing the end face as an example:

[0030] Two 2-φd3 holes are processed on the plug cover 10, one hole is connected to the gas, and the other hole is connected to the gas pressure gauge, and the hole diameter φd3 ≥ φd2; according to the formula L11 = 0.433D11 Calculate the solid thickness L11 of the plugging cover, L11: solid thickness of the plugging cover; D11: matches with the outer circle of the stopper of the cylinder head 11, with a matching clearance of 0.05~0.1mm; Pmax: experimental pressure; [σ]: allowable stress of the material, with a safety factor of 3.5~5; after the plugging cover 10 is connected to the cylinder head 11, there should be a clearance of 0.5~1mm between the cylinder head 11 and the end face of the plugging cover 10 to facilitate the sealing; (There is an inclined groove processed on the end face of the cylinder head 11, and only end face sealing can be adopted) The end face sealing groove is designed according to the physical size L1 of the end face groove of the cylinder head 11. The radius of the outer diameter D14 of the sealing groove is equal to the groove bottom L1, the inner diameter D10 is equal to the outer diameter of the thread MD, and the depth L12 ensures that the rubber sealing gasket is 0.5~1mm higher after installation; the screw hole distance D12 is equal to the screw hole distance of the cylinder head 11.

[0031] A through hole φd2 is drilled in the center of the DN quick-change connector 4. φD2 and φD3 are matched with the gas shut-off valve connector 7 according to the clearances of H9 / f7 and H11 / d11 respectively. An O-ring sealing groove and a U-shaped pin installation groove are processed on the DN quick-change connector 4. The DN quick-change connector 4 and the gas shut-off valve connector 7 are assembled together and fixed with a U-shaped pin 5.

[0032] A through hole φd4 is made in the center of the gas stop valve connector 7, one end of which is clearance-matched with the DN quick-change connector 4, and the other end is threadedly connected to the disc handle external thread single nozzle valve. The aperture φd4 is equal to the inner hole size of the disc handle external thread single nozzle valve, and raw tape is wrapped around the threads of the disc handle external thread single nozzle valve to ensure the sealing of the threaded connection.

[0033] The elbow 9 is made of oil pipe, and in order to prevent the debris not cleaned in the cylinder cavity from entering the pressure gauge cavity, the elbow 9 is heated and bent. One end of the elbow 9 is welded to the plug cover 10, and the other end is welded to the pressure gauge joint 8.

[0034] A through hole φd1 is made in the center of the pressure gauge connector 8. φd1 is smaller than the bottom hole of the pressure gauge MD1 thread and is greater than or equal to the center hole diameter of the pressure gauge thread. The size of the pressure gauge connector connection is designed according to the pressure gauge thread size.

[0035] Appropriate O-rings 6 are installed in the sealing grooves φD1 and L2 of the DN quick-change connector 4, which are connected to the gas stop valve connector 7 and fixed with a U-shaped pin 5. The U-shaped pin is a standard part and can be purchased with reference to "MT / T986-2006 U-shaped pin type quick connector and accessories for mining". The matching dimensions of the DN quick-change connector 4 and the gas stop valve connector 7 are designed with reference to "MT / T986-2006 U-shaped pin type quick connector and accessories for mining". The single-mouth valve with external thread and handle is purchased directly.

[0036] A rubber sealing pad 2 is installed in the sealing groove of the plugging cover 10, close to the end face of the cylinder head 11, and fixed with screws to achieve the purpose of end face sealing.

[0037] The DN quick-change connector 4 and the gas stop valve connector 7 are connected and fixed by a U-shaped pin 5, so that the two can be quickly connected and separated, so that the device can be quickly separated from the gas, and the installation and placement of the device are convenient.

[0038] like Figure 2 As shown, the utility model is a welded blind hole cylinder low-pressure air tightness test device. Except for the elbow 9 which is made of the common 20# oil pipe, the other parts can be made of common materials such as 45, 27SiMn, etc., and the tempering treatment is HB240-280.

[0039] The device has easy access to materials for parts, a simple manufacturing process, and low processing costs, and can effectively meet the requirements for low-pressure air tightness testing of welded blind hole cylinders.

Claims

1. A welded blind hole cylinder low-pressure air tightness test device, comprising a plugging cover (10) connected and fixed to a head (11) of a cylinder (1) via a rubber sealing gasket (2), and two through holes formed on the plugging cover (10), characterized in that: A bent pipe (9) is welded at the center of a through hole of the plugging cover (10), a pressure gauge connector (8) connected to the bent pipe (9) is welded at the head of the bent pipe (9), and a gas pressure gauge is installed on the pressure gauge connector (8); a DN quick-change connector (4) is welded at the center of another through hole of the plugging cover (10), the DN quick-change connector (4) is connected and fixed to a gas shut-off valve connector (7) via a U-shaped pin (5) and an O-ring (6), the gas shut-off valve connector (7) is connected to a single nozzle valve with a disc handle through a thread, and then connected to an air compressor to access gas.

2. A welded blind hole cylinder low pressure air tightness test device according to claim 1, characterized in that: A rubber sealing groove is provided on the end surface of the plugging cover (10), and a rubber sealing gasket (2) is installed in the rubber sealing groove. After the plugging cover (10) is connected to the head (11) of the cylinder, a gap of 0.5 to 1 mm is provided between the head (11) of the cylinder and the end surface of the plugging cover (10). After the rubber sealing gasket (2) is installed in the sealing groove of the plugging cover (10), the sealing gasket is 0.5 to 1 mm higher than the end surface of the sealing groove; after the plugging cover (10) is connected and fixed to the head (11) of the cylinder, a gap of 0.5 to 1 mm is provided between the head (11) of the cylinder and the end surface of the plugging cover (10).

3. A welded blind hole cylinder low pressure air tightness test device according to claim 1, characterized in that: A through hole is drilled in the center of the DN quick-change connector (4). The through hole of the DN quick-change connector and the gas shut-off valve connector are matched with clearances of H9 / f7 and H11 / d11 respectively. An O-ring sealing groove and a U-shaped pin mounting groove are processed on the DN quick-change connector. The DN quick-change connector and the gas shut-off valve connector are assembled together and fixed with a U-shaped pin.

4. A welded blind hole cylinder low pressure air tightness test device according to claim 1, characterized in that: A through hole φd4 is provided at the center of the gas stop valve connector (7), one end of which is clearance-matched with the DN quick-change connector (4), and the other end is threadedly connected to the disc handle external thread single nozzle valve, the hole diameter φd4 being equal to the inner hole size of the disc handle external thread single nozzle valve, and raw tape is wrapped around the threads of the disc handle external thread single nozzle valve to ensure the sealing of the threaded connection.

5. A welded blind hole cylinder low pressure air tightness test device according to claim 1, characterized in that: The elbow (9) is a 20# oil pipe fitting and needs to be heated and bent into a spiral shape.

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