Tool for cylinder cover inner cavity pressure test

Abstract

The invention discloses a tool and method for testing the pressure of an inner cavity of a cylinder cover, and belongs to the technical field of machining detection. The tool comprises a base, a vertical side face supporting plate, an upper plane limiting sealing plate, a valve seat sealing cover, an upper oil injection hole sealing blank cap, a lower oil injection hole sealing blank cap, an E1 / E2 type blank cap and a supporting bolt. Precise positioning of the cylinder cover is achieved through the center positioning hole of the base, pressurization of the whole cavity is completed through the single water inlet (1a), the detachable design of the modular sealing assembly is matched, and the technical problems that according to a traditional method, repeated disassembly and assembly are needed, and sealing reliability is poor are solved. According to the invention, the 2.5 MPa pressure test of all inner cavities can be completed at one time, the repeated utilization rate of the blank cap is improved, and the detection cost is reduced. The device is suitable for quality detection of medium-and-high-speed machine cylinder covers, and has the characteristics of simple operation, safety, reliability and strong adaptability.

Description

Technical Field

[0001] The present invention relates to the field of mechanical processing technology, in particular to a tool for testing the inner cavity pressure of a cylinder head, and is particularly suitable for testing the sealing performance of the cylinder head of a medium- and high-speed engine. Background Art

[0002] The cylinder head structure of a medium- and high-speed diesel engine (or engine, depending on the specific application scenario) is extremely complex. Its shape is irregular and variable, and its internal cavity is equipped with a crisscrossing network of cooling water channels, which are interconnected and form a complex cooling circulation system. Critically, the water inlet ports of each channel are not uniformly distributed, resulting in significant differences in water flow distribution and pressure conduction characteristics. This poses a significant challenge to the pressure tightness testing of the cylinder head.

[0003] The traditional pressure testing method currently used in the industry for this type of cylinder head has numerous limitations. This method requires multiple pumping operations to gradually reach the specified test pressure. This process is not only time-consuming but also requires a high level of operator skill and experience. Operators must precisely control the amplitude and rhythm of each pumping operation to ensure balanced pressure across all water channels and within safe limits. Any inadvertent misstep could result in test failure.

[0004] In addition, the preparation work before the pump pressure test is also extremely tedious and difficult. The operator must first accurately install the product covers around the cylinder head. These covers must not only ensure good sealing, but also perfectly match the complex structure of the cylinder head. During the installation process, any slight deviation may affect the subsequent pump pressure test results. Once the cover is found to be improperly installed or leaks occur during the pump pressure process, it is often necessary to destroy the installed cover, reinstall and debug it, and then conduct the pump pressure test again. This repeated disassembly and assembly process not only consumes a lot of manpower, material resources and time costs, but may also cause a certain degree of damage to the cylinder head and the cover itself, increasing the product defect rate and maintenance costs.

[0005] Therefore, there is an urgent need to optimize and improve the existing pressure test methods to improve detection efficiency and reduce operation difficulty and cost. Summary of the Invention

[0006] The purpose of this invention is to provide a new pressure test fixture that can complete the test work of all cavities with a single pump pressure, eliminating the need for multiple test operations. In addition, the use of a self-made bulkhead for installation and pumping can achieve completely non-destructive replacement, low inspection cost, and convenient and fast operation.

[0007] To achieve the above object, the technical solution of the present invention is as follows:

[0008] A tool for cylinder head inner cavity pressure test, which is characterized by comprising:

[0009] The base has a positioning step hole at its center that matches the large outer circle of the lower plane of the cylinder head, and a water inlet connected to the center hole on the bottom side for injecting pressure medium into the entire inner cavity;

[0010] A vertical side support plate is fixed around the base, and has a long key slot at the bottom for adjusting the position;

[0011] An upper plane limiting sealing plate (3) is fixed to the upper plane of the cylinder head and is located above the oil injection hole sealing upper cover (5);

[0012] A valve seat sealing cover (4) is assembled in the exhaust valve seat hole of the cylinder head, and has two sealing ring grooves on its outer circle;

[0013] The oil injection hole sealing upper cover (5) and the oil injection hole sealing lower cover (6) are respectively assembled on the upper and lower parts of the cylinder head oil injector hole, and the outer circles of the oil injection hole are both provided with sealing ring grooves;

[0014] The E1 type blind cover (7) and the E2 type blind cover (8) are assembled in the water plugging holes around the cylinder head, and the outer circumferences thereof are provided with sealing ring grooves;

[0015] The tightening bolt (9) is screwed to the threaded hole on the vertical side support plate (2), and the end portion thereof abuts against the outer end surface of the E1 type blind cover (7) and the E2 type blind cover (8).

[0016] Preferably, the positioning step hole of the base (1) forms a main positioning with the cylinder head, and a fixed connection is achieved through four cylinder head bolt holes.

[0017] Preferably, the vertical side support plate (2) is fixed to the base (1) by anchor bolts, and its end surface is provided with a plurality of threaded holes for installing support bolts (9) of different lengths.

[0018] Preferably, the upper plane limiting sealing plate (3) is fixed through bolt holes on the upper plane of the cylinder head, and its lower surface contacts and limits the upper end surface of the oil injection hole sealing cover (5).

[0019] Preferably, the valve seat sealing cover (4) forms a double seal with the exhaust valve seat hole through O-rings in two sections of sealing ring grooves on its outer circle.

[0020] Preferably, the oil injection hole sealing upper cover (5) and the oil injection hole sealing lower cover (6) respectively form a seal with the injector hole through the O-ring in the outer circle sealing ring groove thereof, and the oil injection hole sealing upper cover (5) is limited by the upper plane limiting sealing plate (3), and the oil injection hole sealing lower cover (6) is limited by the base (1).

[0021] Preferably, the E1 type blind cover (7) and the E2 type blind cover (8) form a seal with the water plugging hole through the O-ring in the outer circular sealing ring groove thereof, and are tightened and limited by the end of the tightening bolt (9).

[0022] Second, the present invention also provides a cylinder head inner cavity pressure test method, which uses the above-mentioned tooling and is characterized in that it includes the following steps:

[0023] Assemble the valve seat sealing cover (4) to the bottom of the cylinder head exhaust valve seat hole;

[0024] Assemble the fuel injection hole sealing upper cover (5) and the fuel injection hole sealing lower cover (6) to the upper and lower parts of the fuel injector hole respectively;

[0025] Assemble the E1 type blind cover (7) and the E2 type blind cover (8) to the surrounding water plugging holes;

[0026] The cylinder head is positioned and installed in the central step hole of the base (1) through the large outer circle of the lower plane, and fixed with bolts;

[0027] Install the upper plane limit sealing plate (3) and make its lower surface press the oil injection hole to seal the upper cover (5);

[0028] Install the vertical side support plate (2) and adjust the support bolts (9) so that their ends are pressed against the E1 type blind cover (7) and the E2 type blind cover (8);

[0029] Connect the pressure pipe of the water inlet (1a) and perform a pressure test;

[0030] After the test is completed, disassemble the components.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] Through the single water inlet design of the base, one-time overall pressurization of all the inner water channels of the cylinder head is achieved. The double sealing structure design (such as the two-stage sealing ring of the valve seat sealing cover, the O-ring + mechanical limit of the blind cover) is adopted, and the leakage rate is reduced to below 0.05% under the 2.5MPa pressure test. The rigid limiting structure formed by the tightening bolts and the vertical side support plate completely solves the problem of high-pressure falling off of the traditional expansion-type blind cover. The base has a center positioning function. When installing the parts, they can be positioned and installed through the center hole of the tooling and the 4 mounting bolt holes, which can increase the stability of the parts during installation. The water plugging holes around are replaced by the original disposable blind heads that are tightened by deformation to detachable and reusable blind heads, which simplifies the installation method of the water plugging hole blind heads, reduces the operational risks, and improves the fault tolerance of the installation blind heads.

[0033] 2. The test fixture of the present invention is suitable for pressure testing of the inner cavity of the cylinder head. It can be installed once to perform all pressure tests on the entire inner cavity of the cylinder head, with high efficiency and easy operation.

[0034] 3. The test fixture is modular in design and easy to assemble and disassemble. The pressure test of the entire inner cavity can be carried out directly through the water inlet hole on the base. This not only unifies the injection process of the pressure medium, but also simplifies the operation steps, improves the efficiency of the pressure test, and reduces the possibility of misoperation. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is a schematic diagram of the structure of the tooling used for cylinder head inner cavity pressure testing of the present invention.

[0036] Figure 2 This is a schematic diagram of the base

[0037] Figure 3-1 Schematic diagram of vertical side right angle support plate

[0038] Figure 3-2 Schematic diagram of vertical side angled support plate

[0039] Figure 4-1 Schematic diagram of upper plane limit sealing plate

[0040] Figure 4-2 This is a schematic diagram of the upper plane L-shaped limit sealing plate

[0041] Figure 5 Schematic diagram of valve seat sealing cover

[0042] Figure 6 Schematic diagram of the upper and lower covers with holes for sealing

[0043] Figure 7 This is a schematic diagram of E1 and E2 type blind covers. DETAILED DESCRIPTION

[0044] The following is a further description of the special tooling of this patent invention in combination with the accompanying drawings and specific implementation examples, but this should not limit the scope of protection of this patent invention.

[0045] See Figure 1 , Figure 1 The present invention is a schematic structural diagram of a tooling for cylinder head inner cavity pressure testing, as shown in the figure, comprising a base (1), a vertical side support plate (2), an upper plane limit sealing plate (3), a valve seat sealing cover (4), an upper oil injection hole sealing cover (5), a lower oil injection hole sealing cover (6), an E1 type cover (7), an E2 type cover (8) and a tightening bolt (9).

[0046] The base (1) is the installation foundation of the tooling. The central inner hole of the base is the installation and positioning reference of the part. The surrounding support plates are all installed on the base. A through hole is designed on the side of the bottom of the base as a water inlet for pressure testing and connected to the central hole. The vertical side support plate (2) is a welded part, installed on the four sides of the cylinder head of the base (1) and fixed by anchor bolts. The upper plane limit sealing plate (3) is installed on the upper plane of the part and fixed by bolts. The installation limit is performed after the upper cover (5) of the injector hole is installed. The valve seat sealing cover (4) is directly installed in the exhaust valve seat hole of the part and seals the part through two sections of sealing rings on the outer circle. The base (1) is used for limiting. The upper cover (5) of the injection hole sealing is installed on the upper part of the injector hole of the part and seals the part through two sections of sealing rings on the outer circle. The upper plane limit sealing plate (3) is used for limiting. The lower cover (6) of the injection hole sealing is installed on the lower part of the injector hole of the part and seals the part through a section of sealing ring. After installation, the base (1) is used for positioning. The E1 type blind cover (7) is installed on the water plugging holes around the parts, and the parts are sealed by the outer cylindrical sealing ring. The vertical side support plate (2) and the tightening bolts (9) are used for positioning. The E2 type blind cover (8) is installed on the water plugging holes around the parts, and the parts are sealed by the outer cylindrical sealing ring. The vertical side support plate (2) and the tightening bolts (9) are used for positioning. The tightening bolts (9) are installed on the vertical side support plate (2) and are used to limit the E1 type blind cover (7) and the E2 type blind cover (8).

[0047] See Figure 2 The base (1) is the basic part of the entire tooling set. The center step of the base serves as the main positioning installation hole of the cylinder head and also plays a sealing role. It is installed and fixed using four cylinder head bolt holes. Bolt holes are distributed at specific positions on the upper plane of the base (1) for installing the vertical side support plates (2) around it. A single water inlet is designed at the bottom of the base (1) and is directly connected to the center positioning spike.

[0048] Referring to Figure 3, the vertical side support plate (3) is a welded structure installed on the base (1). A long keyway is opened at the bottom to facilitate the front and rear adjustment of the vertical side support plate (3). The end bolt holes are used to install support bolts (9) to limit the E1 type blind cover (7) and E2 type blind cover (8) around the periphery, preventing the blind cover from being pushed out by water pressure during the pressure test, resulting in failure to seal.

[0049] Refer to Figure 4, the upper plane limit sealing plate (3) is installed on the upper plane of the part and clamped through the bolt holes on the upper plane of the part. It is mainly used to limit the sealing cover (5) on the oil injection hole.

[0050] See Figure 5The valve seat sealing cover (4) is installed in the exhaust valve seat hole. A two-stage sealing ring groove is opened on the outer circle for installing the O-ring. It can play a role of separation and sealing. The end face is opened with bolt holes for easy disassembly.

[0051] See Figure 6 The fuel injection hole sealing upper cover (5) and the fuel injection hole sealing lower cover (6) are installed on the upper and lower parts of the fuel injector hole of the component, and the upper and lower parts of the fuel injector hole are sealed through the outer circular annular sealing groove and the O-ring. The upper plane limit sealing plate (3) and the base are used to limit the position during the pressure test to prevent the water pressure from pushing out of the inner hole.

[0052] See Figure 7 The E1 and E2 type blind covers (7) and (8) are installed in the water plug holes around the parts. A sealing ring groove is opened on the outer circle for installing the O-ring. The E1 and E2 type blind covers mainly replace the original product blind covers and can be reused. Disassembly and assembly are convenient and quick.

[0053] The method of use of the present invention is as follows:

[0054] Instructions for use:

[0055] 1. Before installation, the cylinder head body and inner cavity must be thoroughly cleaned to ensure that the water channel and oil channel are free of oil stains.

[0056] 2. Install the valve seat sealing cover (4) in the exhaust seat valve hole of the cylinder head and tap it gently to the bottom with a copper rod.

[0057] 3. Install the upper and lower sealing caps (5) and lower sealing caps (6) of the fuel injection hole above and below the fuel injector hole of the cylinder head, and gently tap them tightly with a copper rod.

[0058] 4. Install E1 and E2 type blind covers (7) and (8) around the cylinder head and tighten them gently with a copper rod.

[0059] 5. Lift the cylinder head, locate the large outer circle of the lower plane, and slowly install it into the center hole of the base (1). Use the four cylinder head bolt holes to fix the parts.

[0060] 6. Use the fixed screw hole position of the upper plane to install the upper plane limit sealing plate (3) to ensure that the oil injection hole sealing cover (5) is limited.

[0061] 7. Install the vertical side support plates (2) all around, adjust their front and rear positions using the key slots on the lower plane, and press firmly. Install support bolts (9) of different lengths in the bolt holes on the vertical side support plates (2), and rotate them until they rest against the E1 and E2 type blind covers (7) (8).

[0062] 8. Install the remaining small blind-head bolts.

[0063] 9. Install the water inlet pipe at the water inlet hole of the base (1), slowly adjust the pressure, and maintain the pressure after the pressure stabilizes, and maintain the pressure for the required time.

[0064] 10. After the pressure is maintained, remove the base (1) drain hole plug. After the water has completely flowed through, remove all tooling and clean the parts.

[0065] The above is a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. The scope of protection of the present invention also includes other obvious changes and substitutions for those skilled in the art.

Claims

1. A tool for cylinder head inner cavity pressure test, characterized in that: include: The base (1) has a positioning step hole at its center that matches the large outer circle of the lower plane of the cylinder head, and a water inlet (1a) in communication with the center hole on the bottom side for injecting pressure medium into the entire inner cavity; A vertical side support plate (2) is fixed around the base (1), and a long key slot with adjustable position is provided at the bottom thereof; An upper plane limiting sealing plate (3) is fixed to the upper plane of the cylinder head and is located above the oil injection hole sealing upper cover (5); A valve seat sealing cover (4) is assembled in the exhaust valve seat hole of the cylinder head, and has two sealing ring grooves on its outer circle; The oil injection hole sealing upper cover (5) and the oil injection hole sealing lower cover (6) are respectively assembled on the upper and lower parts of the cylinder head oil injector hole, and the outer circles of the oil injection hole are both provided with sealing ring grooves; The E1 type blind cover (7) and the E2 type blind cover (8) are assembled in the water plugging holes around the cylinder head, and the outer circumferences thereof are provided with sealing ring grooves; The tightening bolt (9) is screwed to the threaded hole on the vertical side support plate (2), and the end portion thereof abuts against the outer end surface of the E1 type blind cover (7) and the E2 type blind cover (8).

2. The tool for cylinder head inner cavity pressure test according to claim 1, characterized in that: The positioning step hole of the base (1) forms a main positioning with the cylinder head, and is fixedly connected via four cylinder head bolt holes.

3. The tool for cylinder head inner cavity pressure test according to claim 1, characterized in that: The vertical side support plate (2) is fixed to the base (1) via anchor bolts, and its end surface is provided with a plurality of threaded holes for installing support bolts (9) of different lengths.

4. The tool for cylinder head inner cavity pressure test according to claim 1, characterized in that: The upper plane limiting sealing plate (3) is fixed through bolt holes on the upper plane of the cylinder head, and its lower surface contacts and limits the upper end surface of the oil injection hole sealing upper cover (5).

5. The tool for cylinder head inner cavity pressure test according to claim 1, characterized in that: The valve seat sealing cover (4) forms a double seal with the exhaust valve seat hole through O-rings in two sections of sealing ring grooves on its outer circle.

6. The tool for cylinder head inner cavity pressure test according to claim 1, characterized in that: The oil injection hole sealing upper cover (5) and the oil injection hole sealing lower cover (6) respectively form a seal with the injector hole through the O-ring in the outer circle sealing ring groove, and the oil injection hole sealing upper cover (5) is limited by the upper plane limiting sealing plate (3), and the oil injection hole sealing lower cover (6) is limited by the base (1).

7. The tool for cylinder head inner cavity pressure test according to claim 1, characterized in that: The E1 type blind cover (7) and the E2 type blind cover (8) form a seal with the water plugging hole through the O-ring in the outer circle sealing ring groove, and are tightened and limited by the end of the supporting bolt (9).

8. A cylinder head inner cavity pressure test method, using the tooling according to any one of claims 1 to 7, characterized in that: The following steps are involved: Assemble the valve seat sealing cover (4) to the bottom of the cylinder head exhaust valve seat hole; Assemble the fuel injection hole sealing upper cover (5) and the fuel injection hole sealing lower cover (6) to the upper and lower parts of the fuel injector hole respectively; Assemble the E1 type blind cover (7) and the E2 type blind cover (8) to the surrounding water plugging holes; The cylinder head is positioned and installed in the central step hole of the base (1) through the large outer circle of the lower plane, and fixed with bolts; Install the upper plane limit sealing plate (3) and make its lower surface press the oil injection hole to seal the upper cover (5); Install the vertical side support plate (2) and adjust the support bolts (9) so that their ends are pressed against the E1 type blind cover (7) and the E2 type blind cover (8); Connect the pressure pipe of the water inlet (1a) and perform a pressure test; After the test is completed, disassemble the components.

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