阅读说明：本技术 一种防止漏烟的异形波形衬垫 (Special-shaped waveform liner capable of preventing smoke leakage ) 是由 刘云霞 谢亮 黄兰杰 赵祎 黄立荣 于 2020-07-02 设计创作，主要内容包括：本发明公开了一种防止漏烟的异形波形衬垫,属于密封垫技术领域,包括衬垫本体、设置在衬垫本体两侧的两个安装孔以及分别设置在两个安装孔旁边的两个定位孔；衬垫本体由形状大小结构都一致的波形垫片一、波形垫片二以及波形垫片三三层波形垫片点焊在一起构成；“波形垫片”由本体段、斜面段及平面段一体成型；斜面段及平面段在排气孔密封区形成凸筋；波形垫片一与波形垫片二相对设置,两者的本体段紧密贴合焊接在一起,波形垫片三与波形垫片二相对设置,两者的平面段紧密贴合焊接在一起；波形垫片三与波形垫片一平行设置。本发明在保证外形安装尺寸不变的情况下,利用波形弥补了安装时螺栓预紧造成的衬垫变形,保证了衬垫的密封性。(The invention discloses a special-shaped waveform gasket for preventing smoke leakage, which belongs to the technical field of sealing gaskets and comprises a gasket body, two mounting holes arranged at two sides of the gasket body and two positioning holes respectively arranged beside the two mounting holes; the gasket body is formed by spot welding a first waveform gasket, a second waveform gasket and a third waveform gasket which are consistent in shape, size and structure; the 'wave-shaped gasket' is formed by integrally forming a body section, an inclined plane section and a plane section; the inclined plane section and the plane section form a convex rib in the exhaust hole sealing area; the first wave-shaped gasket and the second wave-shaped gasket are oppositely arranged, the body sections of the first wave-shaped gasket and the second wave-shaped gasket are tightly jointed and welded together, the third wave-shaped gasket and the second wave-shaped gasket are oppositely arranged, and the plane sections of the first wave-shaped gasket and the second wave-shaped gasket are tightly jointed and welded together; the wave-shaped gasket III is arranged in parallel with the wave-shaped gasket I. Under the condition of ensuring that the appearance installation size is not changed, the invention utilizes the waveform to compensate the deformation of the gasket caused by bolt pre-tightening during installation, thereby ensuring the sealing property of the gasket.)

1. The utility model provides a prevent leaking special-shaped wave form liner of cigarette, includes liner body (8), sets up two mounting holes (9) in liner body (8) both sides and sets up two locating holes (10) on two mounting holes (9) next door respectively, its characterized in that: the gasket body (8) is formed by spot welding a first wave-shaped gasket (11-1), a second wave-shaped gasket (11-2) and a third wave-shaped gasket (11-3) which are consistent in shape, size and structure; the first wave-shaped gasket (11-1), the second wave-shaped gasket (11-2) and the third wave-shaped gasket (11-3) are all integrally formed by the body section, the slope section and the plane section; the slope surface section and the plane surface section form a convex rib (11) in the exhaust hole sealing area; the first wave-shaped gasket (11-1) and the second wave-shaped gasket (11-2) are arranged oppositely, and body sections of the first wave-shaped gasket and the second wave-shaped gasket are tightly jointed and welded together; the third wave-shaped gasket (11-3) and the second wave-shaped gasket (11-2) are arranged oppositely, and the plane sections of the third wave-shaped gasket and the second wave-shaped gasket are tightly jointed and welded together; the third wave-shaped gasket (11-3) and the first wave-shaped gasket (11-1) are arranged in parallel.

2. The contoured gasket for preventing smoke leakage as set forth in claim 1, wherein: the first wave-shaped gasket (11-1), the second wave-shaped gasket (11-2) and the third wave-shaped gasket (11-3) are all made of stainless steel.

3. The contoured gasket for preventing smoke leakage as set forth in claim 1, wherein: the horizontal length L of the slope surface section is 2 mm.

4. The contoured gasket for preventing smoke leakage as set forth in claim 1, wherein: the vertical distance H between the body section and the plane section is 0.6 +/-0.1 mm.

5. A shaped wave liner for preventing smoke leakage according to any one of claims 1 or 2, wherein: the materials of the first wave-shaped gasket (11-1), the second wave-shaped gasket (11-2) and the third wave-shaped gasket (11-3) are all 12Cr17Ni 7-GB/T3280.

Technical Field

The invention relates to the technical field of sealing gaskets, in particular to a special-shaped waveform gasket for preventing smoke leakage, which is used at the joint of an exhaust main pipe and a cylinder cover of a diesel engine.

Background

The exhaust main pipe of the diesel engine and the cylinder cover are sealed by adopting a non-metal composite material sealing gasket, the vent hole of the sealing gasket is provided with a heat-resistant steel edge, and the sealing performance of the connecting part is ensured by screwing two fastening bolts. However, when the diesel engine is used, a gap is formed between the connecting surface of the exhaust main pipe and the cylinder cover, the sealing is not tight, high-temperature waste gas escapes from the gap, so that the high-temperature waste gas is generally known as smoke leakage, black carbon deposition occurs at the position flushed by the high-temperature waste gas, and meanwhile, the substrate part made of the asbestos plate lining the exhaust main pipe is ablated by the high-temperature waste gas. As shown in fig. 1 and 2.

The joint of the exhaust main pipe and the cylinder cover has smoke leakage in the using process of the diesel engine, so that the liner of the exhaust main pipe is ablated, and the normal use of the diesel engine is influenced. The deformation condition of the original liner is found through actual measurement and measurement of the load in the bolt tightening state and simulation analysis.

Disclosure of Invention

The technical problem to be solved by the invention is to provide the special-shaped corrugated liner for preventing smoke leakage, wherein the vent hole of the liner is set to be a three-layer gasket with a certain corrugated height, and the three-layer gasket is combined in a special structure, so that the mounting and sealing requirements of the exhaust pipe are met, and the problem that the exhaust pipe liner is damaged in the using process is solved.

In order to solve the technical problems, the technical scheme adopted by the invention is as follows:

a special-shaped waveform liner for preventing smoke leakage comprises a liner body, two mounting holes arranged at two sides of the liner body and two positioning holes respectively arranged beside the two mounting holes; the gasket body is formed by welding a first waveform gasket, a second waveform gasket and a third waveform gasket which are consistent in shape, size and structure; the first wave-shaped gasket, the second wave-shaped gasket and the third wave-shaped gasket are all integrally formed by the body section, the inclined plane section and the plane section; the inclined plane section and the plane section form a convex rib in the exhaust hole sealing area; the first wave-shaped gasket and the second wave-shaped gasket are oppositely arranged, and body sections of the first wave-shaped gasket and the second wave-shaped gasket are tightly attached and welded together; the third wave-shaped gasket and the second wave-shaped gasket are oppositely arranged, and the plane sections of the third wave-shaped gasket and the second wave-shaped gasket are tightly jointed and welded together; the wave-shaped gasket III is arranged in parallel with the wave-shaped gasket I.

The technical scheme of the invention is further improved as follows: the first wave-shaped gasket, the second wave-shaped gasket and the third wave-shaped gasket are all made of stainless steel.

The technical scheme of the invention is further improved as follows: the horizontal length L of the slope surface section is 2 mm.

The technical scheme of the invention is further improved as follows: the vertical distance H between the body section and the plane section is 0.6 +/-0.1 mm.

The technical scheme of the invention is further improved as follows: the first wave-shaped gasket, the second wave-shaped gasket and the third wave-shaped gasket are all made of 12Cr17Ni 7-GB/T3280.

Due to the adoption of the technical scheme, the invention has the technical progress that:

1. the invention adopts pure metal stainless steel material as the liner, and the liner can not be burnt out even if smoke leaks.

2. The gasket is arranged into three layers of gaskets with certain wave-shaped height, the three layers of gaskets are combined in a special structure, and the vent holes are arranged into the convex ribs, so that the mounting and sealing requirements of the exhaust pipe are met, and the problem that the exhaust pipe gasket is damaged in the using process is solved.

3. The positioning holes are arranged beside the mounting holes, so that positioning of the gasket during mounting is guaranteed, dislocation of the gasket is prevented, positioning accuracy of the three layers of wave-shaped gaskets during combination is guaranteed, and sealing performance of the gasket is guaranteed.

4. Under the condition of ensuring that the appearance installation size is not changed, the invention utilizes the waveform to compensate the deformation of the gasket caused by bolt pre-tightening during installation, thereby effectively ensuring the sealing property of the gasket.

Drawings

FIG. 1 is a schematic view of the installation of an exhaust manifold gasket;

FIG. 2 is a schematic view of the original pad structure;

FIG. 3 is a schematic view of the overall structure of the present invention;

FIG. 4 is an enlarged sectional view of A-A of the present invention;

FIG. 5 is a three-dimensional model of a gasket assembly;

FIG. 6 is an assembly mesh generation model;

FIG. 7 is an assembly equivalent stress cloud;

FIG. 8 is a cloud of liner compression stresses;

FIG. 9 is a Z-direction displacement cloud of the assembly;

fig. 10 is a Z-direction displacement cloud of the pad.

The device comprises an exhaust manifold 1, an exhaust manifold 2, bolts 3, a gasket 4, a cylinder cover 5, a stainless steel edge covering 6, an asbestos plate 7, a double-sided hook plate 8, a gasket body 9, a mounting hole 10, a positioning hole 11, a convex rib 11-1, a first wave-shaped gasket 11-2, a second wave-shaped gasket 11-3 and a third wave-shaped gasket.

Detailed Description

The invention relates to a special-shaped waveform gasket for preventing smoke leakage, which is designed aiming at the problem that smoke leakage exists at the joint of an exhaust main pipe and a cylinder cover of a diesel engine in the using process and the liner of the exhaust main pipe is easy to ablate.

The present invention will be described in further detail with reference to FIGS. 1 to 10:

as shown in fig. 3 and 4, the special-shaped corrugated liner for preventing smoke leakage comprises a liner body 8, two mounting holes 9 arranged at two sides of the liner body 8 and two positioning holes 10 respectively arranged beside the two mounting holes 9; the gasket body 8 is formed by spot welding a first wave-shaped gasket 11-1, a second wave-shaped gasket 11-2 and a third wave-shaped gasket 11-3 which are consistent in shape, size and structure; the first wave-shaped gasket 11-1, the second wave-shaped gasket 11-2 and the third wave-shaped gasket 11-3 are all integrally formed by the body section, the slope section and the plane section; the slope surface section and the plane surface section form a convex rib 11 in the exhaust hole sealing area; the first wave-shaped gasket 11-1 and the second wave-shaped gasket 11-2 are arranged oppositely, and body sections of the first wave-shaped gasket and the second wave-shaped gasket are tightly jointed and welded together; the third wave-shaped gasket 11-3 and the second wave-shaped gasket 11-2 are arranged oppositely, and the plane sections of the third wave-shaped gasket and the second wave-shaped gasket are tightly jointed and welded together; the wave-shaped gasket III 11-3 and the wave-shaped gasket I11-1 are arranged in parallel.

The first wave-shaped gasket 11-1, the second wave-shaped gasket 11-2 and the third wave-shaped gasket 11-3 are all made of stainless steel materials which are all 12Cr17Ni 7-GB/T3280.

The horizontal length L of the slope surface section is 2 mm.

The vertical distance H between the body section and the plane section is 0.6 +/-0.1 mm.

The working principle is as follows:

as shown in fig. 1: the exhaust manifold 1, the gasket 3 and the cylinder head 4 are fastened together by bolts 2, and the gasket 3 performs a sealing function.

The material of the exhaust manifold 1 is SiMo 51; the bolt 2 is made of 42 CrMo; the cylinder cover 4 is made of HT 250;

as shown in figure 2, the liner 3 is made of asbestos-reinforced vertical plate composite material and comprises a stainless steel edge cover 5, an asbestos plate 6 and a double-sided vertical hook plate 7.

Through actual measurement of the load of the bolt 2 in a tightened state and simulation analysis, the deformation of the gasket 3 is found:

(1) measuring the actual stress of the pad 3

The bolt 2 is applied with a tightening torque of 65Nm according to the assembly requirement, and after the tightening torque and the unloading torque are repeatedly applied and experimental data are processed, the pressure of the bolt on the annular load cell in the state is about 2040kg, the gravity acceleration is 9.8m/s, and the pressure can be converted into the pre-tightening force of 19992N, so that the load of a single bolt is 19992N.

(2) Liner 3 assembly simulation calculation

The three-dimensional model of the cylinder head 4 and the exhaust manifold 1 is simplified, and the simplified assembly model is shown in fig. 5.

The method comprises the steps of setting corresponding material properties in abaqus and endowing corresponding sections with the corresponding properties, setting the contact part of a bolt 2 and a cylinder cover 4 to be in binding contact, setting the bolt 2-an exhaust main pipe 1, the exhaust main pipe 1-a gasket 3 and the gasket 3-the cylinder cover 4 to be in frictional contact with a friction coefficient of 0.1, respectively applying pretightening force with the size of 20000N (which is calibrated through experiments) to two exhaust pipe bolts 2 on the section of an arrow in figure 5, applying full displacement constraint to the bottom surface of the cylinder cover 4, and respectively performing mesh subdivision on each part, wherein the pretightening force is shown in figure 6.

The calculation result is analyzed, and after the bolt pre-tightening force is applied, an equivalent stress cloud chart of the assembly body is shown in fig. 7, and it can be seen that a region with larger stress is mainly distributed on the bolt 2. The cloud of the pressing force on the surface of the gasket 3 is shown in fig. 8, and the largest part of the pressing force appears on the annular metal surface of the gasket 3 near the two bolts 2, which is a phenomenon of local pressure stress surge generated by tightening the bolts 2. Fig. 9 shows a displacement cloud chart of the assembly body in the vertical direction, and it can be seen that the bolt head has a sinking trend at the opening of the U-shaped groove after the bolt 2 is screwed down, and the exhaust manifold 1 has a deformation trend of being convex upwards. Fig. 10 is a deformation displacement cloud chart of the gasket 3, and it can be seen that the gasket 3 is distorted and deformed in a state where the bolt 2 is tightened after the deformation trend is enlarged by 200 times.

The sealing pressure distribution of the gasket 3 and the tendency of the sealing pressure change due to the material property change and thermal expansion at high temperature were analyzed. Under the working condition of 600 ℃, the elastic modulus of the material is reduced due to the difference of the thermal expansion coefficients of the parts and high temperature, so that the sealing pressure on the gasket 3 is seriously reduced, the gasket 3 is close to a line contact state, and the smoke leakage fault of the exhaust manifold is easily caused.

According to simulation analysis results, the special-shaped waveform gasket for preventing smoke leakage is designed, under the condition that the appearance installation size is not changed, the deformation of the gasket caused by bolt pre-tightening during installation is compensated by utilizing waveforms, the sealing performance of the gasket is ensured, and the improved gasket structure is shown in figures 3 and 4.

According to the actual measurement of the tightening torque 65Nm of the bolt 2, the load of a single bolt is 19992N, and the total bolt load borne by the gasket 3 is as follows: 2 × 19992= 39984N; design liner 3 wave bus length: 200mm, distributing bolt load to the line length, calculating line pressure: 39984N/200mm = 199.92N/mm.

According to the compression characteristic curve of the gasket 3, the linear pressure required by the single-layer gasket compression is about 180N/mm, so that the waveform of one layer of gasket cannot meet the requirement, the safety coefficient is considered, and the gasket 3 is formed by selecting 3 layers of waveform gaskets for spot welding to meet the design requirement.

In conclusion, the vent holes of the gasket are arranged into the three layers of gaskets with certain wave-shaped height, and the three layers of gaskets are combined in a special structure, so that the mounting and sealing requirements of the exhaust pipe are met, and the problem that the exhaust pipe gasket is damaged in the using process is solved; under the condition of ensuring that the appearance installation size is not changed, the deformation of the gasket caused by bolt pre-tightening during installation is compensated by utilizing the waveform, and the sealing property of the gasket is ensured.