Pressure test tool for hydraulic nut

Abstract

An oil groove is formed in the end face of the hydraulic nut, a piston is installed in the oil groove, at least two oil holes are formed in the outer side wall of the hydraulic nut, the oil holes are communicated with the oil groove, the pressure test tool comprises a bottom plate, a plurality of first through holes are formed in the circumferential direction of the bottom plate, and the center of the bottom plate is used for containing the hydraulic nut; the first through holes are formed in the circumferential direction of the hydraulic nut; a plurality of second through holes are formed in the pressing plate in the circumferential direction of the pressing plate, and when the pressing plate is pressed on the hydraulic nut, the first through holes correspond to the second through holes; each fastener penetrates through the corresponding first through hole and the corresponding second through hole to fix the hydraulic nut between the bottom plate and the pressing plate; the hydraulic pump is connected with at least one oil hole through a hydraulic oil pipe and provides hydraulic pressure; the sealing pieces are used for blocking the oil holes which are not connected with the hydraulic oil pipe, so that the oil groove forms a sealed space. The method has the advantages of simplicity and safety in operation and wide applicability.

Description

Technical Field

[0001] This invention relates to the field of hydraulic nut testing, and particularly to a testing fixture for hydraulic nuts. Background Technology

[0002] Generally, after the hydraulic nut is processed and installed, a pressure test is required to verify whether its rated pressure matches the design requirements and to check for oil leakage during pressurization. Existing technology uses a relatively simple hydraulic nut pressure testing fixture, which connects the two plates by installing the hydraulic nut between two plates and connecting them with a single bolt passing through the center of the nut. This type of hydraulic nut pressure testing fixture is only suitable for hydraulic nuts with relatively low rated pressures. If slightly higher pressure is applied, the bolt in the middle may break, posing a safety hazard.

[0003] The statements herein provide only background information in relation to this invention and do not necessarily constitute prior art. Summary of the Invention

[0004] The purpose of this invention is to provide a pressure testing fixture for hydraulic nuts, suitable for pressure testing of large marine hydraulic nuts, and to eliminate safety hazards in pressure testing.

[0005] To achieve the above objectives, the present invention provides a testing fixture for a hydraulic nut. The hydraulic nut has an oil groove on its end face, a piston is installed within the oil groove, and at least two oil holes are provided on the outer side wall of the hydraulic nut, communicating with the oil groove. The fixture includes: a base plate with a plurality of first through holes along its circumference, the center of which is used to place the hydraulic nut, and the first through holes are arranged around the circumference of the hydraulic nut; a pressure plate with a plurality of second through holes along its circumference, wherein when the pressure plate presses on the hydraulic nut, the plurality of first through holes correspond to the plurality of second through holes; a plurality of fasteners, each fastener passing through a corresponding first through hole and second through hole, fixing the hydraulic nut between the base plate and the pressure plate; a hydraulic pump connected to at least one of the oil holes via a hydraulic oil pipe to provide hydraulic pressure; and at least one seal for blocking oil holes not connected to the hydraulic oil pipe, thus forming a sealed space in the oil groove.

[0006] In one embodiment, the number of fasteners is not less than 16.

[0007] In one embodiment, the number of fasteners ranges from 16 to 20.

[0008] In one embodiment, the fastener is at a distance of not less than 100 mm from the edge of the base plate or the edge of the pressure plate.

[0009] In one embodiment, the fastener is a bolt and a nut, the bolt passing through the first through hole and the second through hole in sequence, and tightened by the nut to fix the hydraulic nut between the base plate and the pressure plate.

[0010] In one embodiment, the thickness of the base plate and the pressure plate is not less than 100 mm.

[0011] In one embodiment, the testing fixture for the hydraulic nut further includes a support platform located below the base plate for supporting the base plate.

[0012] In one embodiment, a pad is further provided between the upper surface of the support platform and the lower surface of the base plate to form a gap between the support platform and the base plate.

[0013] In one embodiment, the base plate and the pressure plate are made of carbon steel.

[0014] Compared with the prior art, the hydraulic nut testing fixture provided by the present invention has at least the following beneficial effects: (1) It is simple and safe to operate. It only requires controlling the hydraulic pressure provided by the hydraulic pump to control the different pressure levels of the hydraulic nut. (2) It has wide applicability. It is not only suitable for small hydraulic nuts, but also for large hydraulic nuts. Therefore, it is not necessary to make a separate testing fixture for each hydraulic nut, which reduces the test cost. (3) By setting several fasteners around the circumference of the hydraulic nut, the force on the individual fasteners is distributed, preventing the fasteners from being pulled apart and improving the safety of the test. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the testing fixture for the hydraulic nut of the present invention; Figure 2 This is a top view of the pressure plate in the testing fixture of the hydraulic nut of the present invention. Detailed Implementation

[0016] The following detailed description of the hydraulic nut testing fixture proposed in this invention, in conjunction with the accompanying drawings and specific embodiments, will further illustrate its advantages and features. The advantages and features of this invention will become clearer from the following description. It should be noted that the drawings are in a very simplified form and use non-precise proportions, intended only to facilitate and clearly illustrate the embodiments of this invention. Please refer to the drawings to make the objectives, features, and advantages of this invention more apparent and understandable. It should be understood that the structures, proportions, sizes, etc., depicted in the accompanying drawings are only for illustrative purposes and to enable those skilled in the art to understand and read them, and are not intended to limit the implementation conditions of this invention. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to the size, without affecting the effects and objectives achieved by this invention, should still fall within the scope of the technical content disclosed in this invention.

[0017] This invention provides a testing fixture for hydraulic nuts to test whether they meet design requirements in the shipbuilding industry. After the hydraulic nut is processed and installed, a certain pressure needs to be applied to test whether it meets the design requirements. Figure 1 As shown, an oil groove 11 is provided on the end face of the hydraulic nut 10, and a piston 12 is installed in the oil groove 11. At least two oil holes are provided on the outer side wall of the hydraulic nut 10. In this embodiment, the two oil holes are a first oil hole 131 and a second oil hole 132, and both the first oil hole 131 and the second oil hole 132 are connected to the oil groove 11.

[0018] Continue to refer to Figure 1 To perform pressure testing on the hydraulic nut 10, the hydraulic nut testing fixture 20 includes: a base plate 21 with a plurality of first through holes 211 along its circumference (e.g., ...). Figure 2 As shown), the center of the base plate 21 is used to place the hydraulic nut 10, and the first through hole 211 is arranged around the circumference of the hydraulic nut 10; the pressure plate 22 has a plurality of second through holes 221 along its circumference (as shown). Figure 2As shown, when the pressure plate 22 presses against the hydraulic nut 10, several first through holes 211 correspond to several second through holes 221; several fasteners 23, each fastener 23 passing through the corresponding first through hole 211 and second through hole 221, fix the hydraulic nut 10 between the base plate 21 and the pressure plate 22; a hydraulic pump 24, which is connected to the first oil hole 131 through a hydraulic oil pipe 25, provides hydraulic pressure; a seal 26 is used to block the second oil hole 132 that is not connected to the hydraulic oil pipe 25, so that the oil groove 11 forms a relatively sealed space. When the hydraulic pump 24 transmits hydraulic oil into the oil groove 11 through the hydraulic oil pipe 25, the hydraulic nut 10 is pressurized to the maximum allowable pressure value of the hydraulic nut, and the pressure is maintained for at least 5 minutes to check for pressure leakage and oil leakage, thus completing the pressure test of the hydraulic nut. In other embodiments, if the hydraulic nut 10 has more than two oil holes, all oil holes except the one connecting to the hydraulic oil pipe 25 are sealed with a seal 26. Alternatively, the seal 26 may be a blind end to achieve the sealing of the oil holes.

[0019] Furthermore, when the hydraulic nut 10 is pressurized significantly, to prevent the fastener 23 from breaking due to excessive tensile force and causing a safety accident, the number of fasteners 23 in this embodiment of the invention is no less than 16. Preferably, the number of fasteners 23 is 16 to 20. If the number of fasteners 23 is less than 16, the tensile force on a single fastener 23 may exceed its bearing capacity. If the number of fasteners 23 is more than 20, the number of first and second through holes on the base plate 21 and pressure plate 22 also needs to be increased. Since the area of ​​the base plate 21 and pressure plate 22 is fixed, the more through holes there are, the greater the processing difficulty, resulting in higher processing costs. For example, as... Figure 1 As shown, the fastener 23 consists of a bolt 231 and a nut 232. The bolt 231 passes through the first through hole 211 and the second through hole 221 in sequence, and is tightened by the nut 232, thereby pressing and fixing the hydraulic nut 10 between the base plate 21 and the pressure plate 22.

[0020] In this embodiment, as Figure 2As shown, the distance d between the fastener 23 and the edge of the base plate 21 or the edge of the pressure plate 22 is not less than 100 mm. If the distance d between the fastener 23 and the edge of the base plate 21 or the edge of the pressure plate 22 is less than 100 mm, the fastener 23 will be too close to the edge. When the hydraulic nut 10 is pressurized, the edges of the pressure plate 22 and the base plate 21 are prone to cracking. However, when the distance d between the fastener 23 and the edge of the base plate 21 or the edge of the pressure plate 22 is greater than or equal to 100 mm, the pressure of the pressure plate 22 on the hydraulic nut 10 is uniform, and it can reduce the excessive local bending deformation of the pressure plate 21 and the base plate 22 near the fastener 23, thus extending the service life of the testing fixture 20. Meanwhile, as a preferred embodiment, the thickness of the base plate 21 and the pressure plate 22 is not less than 100 mm, and the base plate 21 and the pressure plate 22 are made of carbon steel. For example, the carbon steel material can be 45 steel (commonly known as 45# steel) in the national standard high-quality carbon structural steel (GB / T699—1999), and its carbon content is preferably between 0.42% and 0.50% to ensure that the strength of the base plate 21 and the pressure plate 22 can meet the requirements of the pressure test.

[0021] like Figure 1 As shown, the pressure testing fixture 20 also includes a support platform 27, which is located below the base plate 21 and is used to support the base plate 21. Furthermore, a pad 28 is provided between the upper surface of the support platform 27 and the lower surface of the base plate 21 to form a gap 29 between the support platform 27 and the base plate 21, facilitating the tightening of the nut below the base plate 21.

[0022] In one specific embodiment, when performing a pressure test using the hydraulic nut testing fixture 20 provided by the present invention, the following steps are specifically included: S1. Place the base plate 21 on the support platform 27, place the hydraulic nut 10 on the base plate 21, and then cover it with the pressure plate 22. Then, pass 20 bolts 231 through the second through hole 132 and the first through hole 131 in sequence, and tighten the nut 232 to complete the fixing of the hydraulic nut 10.

[0023] S2. The first oil hole 131 of the hydraulic nut 10 is connected to the hydraulic pump 24 (a hydraulic electric pump is used in this embodiment) through the hydraulic oil pipe 25, and the second oil hole 132 is blocked with a plug. S3. The hydraulic electric pump pressurizes the hydraulic nut 10 to the maximum allowable pressure value and holds the pressure for 5 minutes (or longer, depending on the requirements). Check for pressure leakage and oil leakage to complete the pressure test of the hydraulic nut 10.

[0024] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0025] In the description of this invention, it should be understood that the terms "center," "height," "thickness," "upper," "lower," "vertical," "horizontal," "top," "bottom," "inner," "outer," "axial," "radial," and "circumferential," etc., indicating orientation or positional relationships, are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0026] In the description of this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0027] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0028] Although the present invention has been described in detail through the preferred embodiments above, it should be understood that the above description should not be considered as a limitation of the present invention. Various modifications and substitutions to the present invention will be apparent to those skilled in the art after reading the above description. Therefore, the scope of protection of the present invention should be defined by the appended claims.

Claims

1. A hydraulic nut pressure testing tool, the end face of the hydraulic nut is provided with an oil groove, a piston is installed in the oil groove, at least two oil holes are provided on the outer side wall of the hydraulic nut, the oil holes are communicated with the oil groove, characterized in that, The application relates to a hydraulic nut fixing device, which comprises the following parts: a bottom plate, which is provided with a plurality of first through holes in the circumferential direction, and the center of the bottom plate is used for placing the hydraulic nut, and the first through holes are arranged around the circumferential direction of the hydraulic nut; a pressing plate, which is provided with a plurality of second through holes in the circumferential direction, and when the pressing plate is pressed on the hydraulic nut, the plurality of first through holes correspond to the plurality of second through holes; a plurality of fasteners, each of which passes through the corresponding first through hole and second through hole to fix the hydraulic nut between the bottom plate and the pressing plate; a hydraulic pump, which is connected with at least one oil hole through a hydraulic oil pipe to provide hydraulic pressure; at least one sealing element, which is used for blocking the oil hole which is not connected with the hydraulic oil pipe, so that the oil groove forms a sealed space.

2. The pressurization tool of claim 1, wherein, The number of the fasteners is not less than 16.

3. The pressurization tool of claim 2, wherein, The number of the fasteners ranges from 16 to 20.

4. The pressurization tool of claim 1, wherein, The distance between the fasteners and the edge of the bottom plate or the edge of the pressing plate is not less than 100 mm.

5. The pressure testing kit of any one of claims 1 to 4, wherein the pressure testing kit further comprises a pressure gauge. The fasteners are bolts and nuts, the bolts pass through the first through holes and the second through holes in sequence, and the bolts are screwed through the nuts to fix the hydraulic nut between the bottom plate and the pressing plate.

6. The pressurization tool of claim 1, wherein, The thickness of the bottom plate and the pressing plate is not less than 100 mm.

7. The pressurization tool of claim 1, wherein, The application further comprises: a supporting platform, which is located below the bottom plate and is used for supporting the bottom plate.

8. The pressure testing kit of claim 7, wherein, A cushion block is further arranged between the upper surface of the supporting platform and the lower surface of the bottom plate to form a gap between the supporting platform and the bottom plate.

9. The pressurization tool of claim 6, wherein, The bottom plate and the pressing plate are made of carbon steel.

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