Heat-resistant rubber-coated sleeve with reduced deformation and preparation process therefor

Abstract

A heat-resistant rubber-coated sleeve with reduced deformation and a preparation process therefor. The sleeve comprises a steel sleeve and a rubber sleeve; the rubber sleeve is fitted and sleeved on the outer side of the steel sleeve; a plurality of annular heat dissipation grooves are formed in the outer wall of the steel sleeve; a circular protruding ring is formed between every two annular heat dissipation grooves; four positioning and ventilation grooves are formed in the outer wall of the steel sleeve; and positioning protruding strips fitted in the corresponding positioning and ventilation grooves are arranged on the inner wall of the rubber sleeve. In the heat-resistant rubber-coated sleeve, the plurality of annular heat dissipation grooves are formed in the outer wall of the steel sleeve, a circular protruding ring is formed between every two annular heat dissipation grooves, and when a workpiece is heated, the stress is uniform and consistent, and 50% of the area of the steel sleeve is in contact with the rubber sleeve, thereby relieving the adverse situation of the whole steel sleeve being heated for a long time, also correspondingly relieving the deformation of the steel sleeve, and prolonging the service life of the steel sleeve.

Description

A heat-resistant rubber-coated sleeve with reduced deformation and its preparation process Technical Field

[0001] The present invention relates to the technical field of mechanical sleeve processing, and in particular to a heat-resistant rubber-coated sleeve capable of reducing deformation and a preparation process thereof. Background Art

[0002] Conventional heat-resistant rubber-coated sleeves are used in the export coiling process after heat treatment in the air cushion furnace during the processing of automotive aluminum plates. The surface of the steel sleeve is covered with a relatively soft rubber layer. The outer circle of the steel sleeve and the inner diameter of the rubber layer fit tightly together without any gaps, preventing the rubber layer from loosening and falling off. The rubber layer can improve the surface scratches, indentations, warping of the plate, waves and other quality problems of the aluminum plate.

[0003] For example, application number CN202310271287.0 discloses a heat-resistant rubber-coated sleeve, which includes a steel sleeve body, and the outer side of the steel sleeve body is coated with a heat-resistant rubber layer. In actual operation, the heat obtained by the friction between the surface rubber layer of the heat-resistant rubber-coated sleeve and the automobile aluminum plate is directly released and transferred to the outer surface of the steel sleeve, and then extends to the core of the steel sleeve. The steel sleeve is in a thermal fatigue working state for a long time, causing distortion and deformation, resulting in the outer circle of the rubber-coated sleeve being elliptical, with a circular runout range of 0.7-1.0mm, far exceeding the cylindrical degree requirement of 0.02mm in the drawing design. Accordingly, quality defects such as surface deformation of the aluminum plate are caused.

[0004] Summary of the Invention

[0005] In order to solve the above problems, the present invention proposes a heat-resistant rubber-coated sleeve with reduced deformation and a preparation process thereof, so as to more accurately solve the above problems.

[0006] The present invention is achieved through the following technical solutions:

[0007] The present invention proposes a heat-resistant rubber-coated sleeve with reduced deformation and a preparation process thereof, comprising a steel sleeve and a nitrile rubber sleeve, the nitrile rubber sleeve being fitted on the outside of the steel sleeve, the outer wall of the steel sleeve being provided with a plurality of annular heat dissipation grooves, a circular convex ring being formed between every two annular heat dissipation grooves, the outer wall of the steel sleeve being provided with four positioning ventilation grooves, the slot length of the positioning ventilation groove being consistent with the axial direction of the steel sleeve, the inner wall of the nitrile rubber sleeve being integrally formed with a positioning ridge corresponding to the position of the positioning ventilation groove, and the positioning ridge being fitted and clamped in the corresponding positioning ventilation groove.

[0008] Preferably, the depth of the annular heat dissipation groove is 10-15 mm, the width of the annular heat dissipation groove is the same as the width of the circular convex ring, and the width of the annular heat dissipation groove and the width of the circular convex ring are 10-30 mm.

[0009] Preferably, the cross section of the bottom of the positioning ventilation groove is a semicircular groove, and the bottom of the positioning convex strip is provided with a semicircular concave surface.

[0010] Preferably, the groove depth of the positioning ventilation groove is greater than the groove depth of the annular heat dissipation groove, and the depth of the positioning ridge inserted into the positioning ventilation groove is less than the groove depth of the annular heat dissipation groove.

[0011] Preferably, a plurality of heat dissipation fins are integrally formed on the inner wall of the steel sleeve, and the plurality of heat dissipation fins are arranged at equal intervals along the axial direction of the steel sleeve, and the heat dissipation fins are annular necked fin bodies.

[0012] The above-mentioned preparation process of the heat-resistant rubber-coated sleeve with reduced deformation comprises the following steps:

[0013] S1: The steel sleeve is 35CrM, and has a yield strength of 700-800 MPa, a tensile strength of 800-1000 MPa, an elongation of 7-9%, and a hardness of HB275-315;

[0014] The outer surface of the steel sleeve is ground to make the surface roughness of the steel sleeve Ra < 3.2um;

[0015] S2: The grinding process of the annular heat dissipation groove and the positioning ventilation groove provided on the outer surface of the steel sleeve includes groove rough grinding, groove fine grinding, pickling and flaw detection;

[0016] The grinding feed rate of the groove rough grinding is initially 3-4 μm / s. When the grinding allowance is 0.15-0.2 mm away from the final grinding groove diameter, the grinding feed rate of the groove rough grinding is adjusted to 1 μm / s.

[0017] The grinding feed speed of the groove fine grinding and fine grinding of the groove is 1 μm / s, and the feed amount is ≤50 μm.

[0018] After the groove is finely ground and pickled and ultrasonic testing is passed, the steel sleeve is subjected to quenching and tempering treatment to make the hardness of the steel sleeve HB <229;

[0019] S3: The surface of the steel sleeve is subjected to heat-resistant rubber encapsulation molding treatment to form a nitrile rubber sleeve. During molding, a round sand mold is set in the positioning ventilation groove so that the bottom of the positioning convex strip forms a semicircular inner concave surface. After molding, the round sand mold is destroyed and removed;

[0020] The molding thickness δ of the nitrile rubber sleeve is 10-20 mm, the heat-resistant temperature is 150-230° C., and the Shore hardness is HA82-HA90.

[0021] Beneficial effects of the present invention:

[0022] 1. The present invention has a plurality of annular heat dissipation grooves on the outer wall of the steel sleeve. A circular convex ring is formed between every two annular heat dissipation grooves. When the workpiece is heated, the force is uniform and consistent. 50% of the area of ​​the steel sleeve is in contact with the heat conduction of the nitrile rubber sleeve, and the other half of the heat is in the hollowed annular groove. This alleviates the disadvantageous situation of the steel sleeve being subjected to long-term heating work as a whole, correspondingly alleviates the deformation of the steel sleeve, and increases the service life of the steel sleeve.

[0023] 2. The present invention has four positioning ventilation grooves on the outer wall of the steel sleeve, and positioning ridges are integrally formed on the inner wall of the nitrile rubber sleeve at positions corresponding to the positioning ventilation grooves, and the positioning ridges are fitted into the corresponding positioning ventilation grooves to improve the structural connection between the steel sleeve and the nitrile rubber sleeve, and avoid tangential slippage of the nitrile rubber sleeve on the steel sleeve, and multiple annular heat dissipation grooves can be connected through the positioning ventilation grooves, thereby improving the heat dissipation efficiency in the annular heat dissipation grooves. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] FIG1 is a perspective view of the present invention;

[0025] FIG2 is a front cross-sectional view of the structure of the present invention;

[0026] Figure 3 is an enlarged view of point A in Figure 2;

[0027] FIG4 is a side sectional view of the structure of the present invention;

[0028] FIG5 is an enlarged view of point B in FIG4 .

[0029] In the figure: 1. Steel sleeve; 101. Annular heat dissipation groove; 102. Circular convex ring; 103. Positioning ventilation groove; 104. Heat dissipation fin; 2. Nitrile rubber sleeve; 201. Positioning convex strip; 2011. Semicircular inner concave surface. DETAILED DESCRIPTION

[0030] In order to more clearly and completely illustrate the technical solution of the present invention, the present invention will be further described below with reference to the accompanying drawings.

[0031] Please refer to Figures 1 to 5. A heat-resistant rubber-coated sleeve that reduces deformation includes a steel sleeve 1 and a nitrile rubber sleeve 2. The nitrile rubber sleeve 2 is fitted on the outside of the steel sleeve 1. The yield strength of the annular heat dissipation groove 101 is 700-800 MPa, the tensile strength is 800-1000 MPa, the elongation is 7-9%, the hardness is HB275-315, and the surface roughness is Ra<3.2um, which is suitable for glue hanging, that is, ensuring that the nitrile rubber sleeve 2 and the steel sleeve 1 are wrapped together, and the two generate supporting force and sufficient friction so as not to loosen or fall off.

[0032] As shown in Figures 1 and 4, the outer wall of the steel sleeve 1 is provided with a plurality of annular heat dissipation grooves 101, and a circular convex ring 102 is formed between every two annular heat dissipation grooves 101. The depth of the annular heat dissipation groove 101 is 10-15 mm, and the groove width of the annular heat dissipation groove 101 is the same as the width of the circular convex ring 102. The groove width of the annular heat dissipation groove 101 and the width of the circular convex ring 102 are 10-30 mm. When the workpiece is heated, the force is uniform and consistent. 50% of the area of ​​the steel sleeve 1 is in contact with the heat conduction of the nitrile rubber sleeve 2, and the other half of the heat is in the hollow annular groove, which reduces the adverse situation of the steel sleeve 1 being subjected to long-term heating as a whole, and correspondingly alleviates the deformation of the steel sleeve 1, thereby improving the service life of the steel sleeve 1.

[0033] As shown in Figures 1 and 2, four positioning ventilation grooves 103 are provided on the outer wall of the steel sleeve 1. The slot length of the positioning ventilation grooves 103 is consistent with the axial direction of the steel sleeve 1. The inner wall of the nitrile rubber sleeve 2 is integrally formed with a positioning ridge 201 corresponding to the position of the positioning ventilation grooves 103, and the positioning ridge 201 is fitted and clamped in the corresponding positioning ventilation groove 103. After the steel sleeve 1 and the positioning ridge 201 are assembled, the structural connection between the steel sleeve 1 and the nitrile rubber sleeve 2 is effectively guaranteed, and the tangential slip of the nitrile rubber sleeve 2 on the steel sleeve 1 is avoided.

[0034] As shown in Figures 2 and 3, the cross-section of the bottom of the positioning ventilation groove 103 is a semicircular groove, and the bottom of the positioning ridge 201 is provided with a semicircular inner concave surface 2011, so that axial ventilation and heat dissipation can be carried out between the contact surfaces of the nitrile rubber sleeve 2 and the steel sleeve 1. The groove depth of the positioning ventilation groove 103 is greater than the groove depth of the annular heat dissipation groove 101, and the depth of the positioning ridge 201 inserted into the positioning ventilation groove 103 is less than the groove depth of the annular heat dissipation groove 101, so that multiple annular heat dissipation grooves 101 can be connected through the positioning ventilation groove 103, thereby improving the heat dissipation efficiency in the annular heat dissipation groove 101.

[0035] As shown in Figure 4, the inner wall of the steel sleeve 1 is integrally formed with a plurality of heat dissipation fins 104. The multiple heat dissipation fins 104 are arranged at equal intervals along the axial direction of the steel sleeve 1. The heat dissipation fins 104 are annular necked fin bodies, so that the interior of the steel sleeve 1 can be cooled and ventilated through the heat dissipation fins 104, thereby improving the heat dissipation efficiency.

[0036] A preparation process for a heat-resistant rubber-coated sleeve with reduced deformation comprises the following steps:

[0037] S1: Steel sleeve 1 is 35CrM, and no defects such as cracks, slag inclusions, pinholes, and loose structure are allowed. The yield strength of steel sleeve 1 is 700-800MPa, the tensile strength is 800-1000MPa, the elongation is 7-9%, and the hardness is HB275-315;

[0038] The outer surface of the steel sleeve 1 is polished to a surface roughness of Ra < 3.2 μm, ensuring that the nitrile rubber sleeve 2 and the steel sleeve 1 are wrapped together, generating a supporting force and sufficient friction between the two and preventing them from loosening and falling off;

[0039] S2: The grinding process of the annular heat dissipation groove 101 and the positioning ventilation groove 103 provided on the outer surface of the steel sleeve 1 includes groove rough grinding, groove fine grinding, pickling and flaw detection;

[0040] The grinding feed speed of the groove rough grinding is 3-4μm / s at the beginning of the rough grinding. When the grinding allowance is 0.15-0.2mm away from the final grinding groove diameter, the grinding feed speed of the groove rough grinding is adjusted to 1μm / s.

[0041] The grinding feed speed of groove fine grinding and fine grinding is 1μm / s, and the feed amount is ≤50μm.

[0042] After the groove is finely ground, it is pickled and ultrasonically inspected to ensure that the groove surface is free of defects and grinding wheel marks. After the groove surface is round and uniform, it is tempered to ensure that the hardness of the steel sleeve 1 is HB < 229;

[0043] S3: Heat-resistant rubber is coated on the surface of the steel sleeve 1 to form a nitrile rubber sleeve 2. During the molding process, a round sand mold is set in the positioning ventilation groove 103 to form a semicircular inner concave surface 2011 at the bottom of the positioning convex strip 201. After molding, the round sand mold is destroyed and removed to ensure that the positioning ventilation groove 103 forms a circular ventilation channel as shown in Figure 3;

[0044] The molding thickness δ of the nitrile rubber sleeve 2 is 10-20 mm, the heat-resistant temperature is 150-230° C., the Shore hardness is HA82-HA90, and it has high wear resistance, good heat resistance, and strong adhesion.

[0045] Working principle: The present invention provides a plurality of annular heat dissipation grooves 101 on the outer wall of the steel sleeve 1, and a circular convex ring 102 is formed between every two annular heat dissipation grooves 101. When the workpiece is heated, the force is uniform and consistent. 50% of the area of ​​the steel sleeve 1 is in contact with the heat conduction of the nitrile rubber sleeve 2, and the other half of the heat is in the hollowed annular groove, which alleviates the adverse situation of the steel sleeve 1 being subjected to long-term heating as a whole, and correspondingly alleviates the deformation of the steel sleeve 1, thereby increasing the service life of the steel sleeve 1.

[0046] The present invention provides four positioning ventilation grooves 103 on the outer wall of the steel sleeve 1, and integrally forms positioning ridges 201 on the inner wall of the nitrile rubber sleeve 2 at positions corresponding to the positioning ventilation grooves 103, and the positioning ridges 201 are engaged and clamped in the corresponding positioning ventilation grooves 103, thereby improving the structural connection between the steel sleeve 1 and the nitrile rubber sleeve 2, avoiding tangential slippage of the nitrile rubber sleeve 2 on the steel sleeve 1, and multiple annular heat dissipation grooves 101 can be connected through the positioning ventilation grooves 103, thereby improving the heat dissipation efficiency in the annular heat dissipation grooves 101.

[0047] Of course, the present invention may have many other implementations. Based on this implementation, other implementations obtained by ordinary technicians in this field without any creative work are all within the scope of protection of the present invention.

Claims

1. A heat-resistant rubber-coated sleeve for reducing deformation, comprising a steel sleeve (1) and a nitrile rubber sleeve (2), characterized in that, The nitrile rubber sleeve (2) is fitted and sleeved outside the steel sleeve (1). A plurality of annular heat dissipation grooves (101) are formed on the outer wall of the steel sleeve (1). A circular convex ring (102) is formed between every two annular heat dissipation grooves (101). Four positioning ventilation grooves (103) are formed on the outer wall of the steel sleeve (1). The slotting length of the positioning ventilation grooves (103) is consistent with the axial direction of the steel sleeve (1). A positioning rib (201) is integrally formed on the inner wall of the nitrile rubber sleeve (2) corresponding to the position of the positioning ventilation grooves (103), and the positioning rib (201) is fitted and clamped in the corresponding positioning ventilation grooves (103).

2. The heat-resistant rubber-coated sleeve for reducing deformation according to claim 1, wherein The depth value of the annular heat dissipation grooves (101) is 10 - 15 mm. The groove width of the annular heat dissipation grooves (101) is the same as the width of the circular convex ring (102). The numerical value of the groove width of the annular heat dissipation grooves (101) and the width of the circular convex ring (102) is 10 - 30 mm.

3. A heat-resistant rubber-coated sleeve for reducing deformation according to claim 1, wherein, The cross-section of the bottom of the positioning ventilation grooves (103) is a semi-circular groove. A semi-circular concave surface (2011) is provided at the bottom of the positioning rib (201).

4. A heat-resistant rubber-coated sleeve for reducing deformation according to claim 1, characterized in that, The groove depth value of the positioning ventilation grooves (103) is greater than the groove depth value of the annular heat dissipation grooves (101). The depth value of the positioning rib (201) inserted into the positioning ventilation grooves (103) is less than the groove depth value of the annular heat dissipation grooves (101).

5. A heat-resistant rubber-coated sleeve for reducing deformation according to claim 1, characterized in that, A plurality of heat dissipation fins (104) are integrally formed on the inner wall of the steel sleeve (1). The plurality of heat dissipation fins (104) are arranged at equal intervals along the axial direction of the steel sleeve (1). The heat dissipation fins (104) are annular necked-down fin bodies.

6. The preparation process of a heat-resistant rubber-coated sleeve for reducing deformation according to any one of claims 1-5, characterized in that, Including the following steps: S1: The steel sleeve (1) is 35CrM. The yield strength of the steel sleeve (1) is 700 - 800 MPa, the tensile strength is 800 - 1000 MPa, the elongation is 7 - 9%, and the hardness is HB275 - 315; The outer surface of the steel sleeve (1) is polished so that the surface roughness Ra of the steel sleeve (1) is < 3.2 μm; S2: The grinding process of the annular heat dissipation grooves (101) and the positioning ventilation grooves (103) provided on the outer surface of the steel sleeve (1) includes groove rough grinding, groove fine grinding, pickling and flaw detection; The grinding feed rate of the groove rough grinding is initially 3 - 4 μm / s for rough grinding. When the grinding allowance is still 0.15 - 0.2 mm away from the final grinding groove diameter size, the grinding feed rate of the groove rough grinding is adjusted to 1 μm / s; The grinding feed rate of the groove fine grinding for fine grinding the groove is 1 μm / s, and the feed amount ≤ 50 μm. After pickling and ultrasonic flaw detection are qualified after groove fine grinding, quenching and tempering treatment is carried out to make the hardness HB of the steel sleeve (1) < 229; S3: A heat-resistant rubber encapsulation molding treatment is carried out on the surface of the steel sleeve (1) to form a nitrile rubber sleeve (2). When molding, a round sand mold is arranged in the positioning ventilation grooves (103) so that a semi-circular concave surface (2011) is formed at the bottom of the positioning rib (201), and the round sand mold is damaged and removed after molding; The formed thickness δ of the nitrile rubber sleeve (2) is 10-20 mm, the heat-resistant temperature is 150-230 °C, and the Shore hardness is HA82-HA90.

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