A method for evaluating the bevel welding rate of aluminum laminated oil coolers

Abstract

The present invention discloses a method for evaluating the bevel welding rate of an aluminum laminated oil cooler. The method first measures the height of the rib unit before and after welding, calculates the vertical compression H of the rib unit and the welding rate ψ in the direction normal to the bevel of the rib unit, and then compares and evaluates the vertical compression H and the welding rate ψ with the design specification value to determine whether the product meets the qualified rate after welding. If it fails, the design parameters of the relevant components of the laminated oil cooler are adjusted. The present invention can accurately evaluate the welding rate of the product, is easy to operate, and is timely. During the product processing process, this evaluation method can timely adjust the design parameters of the relevant components of the laminated oil cooler to ensure that the bevel welding rate of the product meets the use requirements, thereby effectively improving the product's airtightness qualified rate, burst strength, and other technical indicators, and has good economic and practicality.

Description

Technical Field

[0001] The invention relates to an evaluation method for the bevel welding rate of an aluminum laminated oil cooler, and belongs to the technical field of laminated oil cooler production. Background Art

[0002] Brazing rate refers to the ratio of the area of ​​molten brazing material that diffuses and penetrates into the gap between the surfaces to be welded to the nominal brazing area. Brazing rate is a key technical indicator for automotive aluminum laminated vacuum brazed oil coolers, significantly impacting the product's airtightness and reliability.

[0003] A stacked oil cooler primarily consists of ribs, a cover plate, a corrugated plate, a base, and a bottom rib. After the components are assembled into a stacked structure, they are clamped in a fixture and then welded in a vacuum brazing furnace. During the welding process, due to the elasticity of components such as the ribs and fins, and the thermal expansion caused by the brazing process, insufficient brazing rate can easily occur between ribs and between ribs and fins. This is especially true at the bevel welds between ribs, where significant deformation increases the likelihood of insufficient brazing rate. In large-scale oil cooler production, testing the brazing rate of each product is labor-intensive and financially intensive. Existing testing methods generally require all products to be processed after they are finished, requiring rework or scrapping of unqualified products. This lack of timely testing leads to material waste, increased production costs, and low efficiency. Therefore, it is crucial to develop a method for evaluating the bevel weld rate of oil coolers during production. Summary of the Invention

[0004] In view of this, an object of the present invention is to provide a method for evaluating the bevel welding rate of an aluminum stacked oil cooler, which can overcome the shortcomings of the prior art.

[0005] The purpose of the present invention is achieved through the following technical solutions:

[0006] A method for evaluating the bevel welding rate of an aluminum laminated oil cooler comprises the following steps:

[0007] s1. Measure the rib unit layer height before and after welding, and calculate the vertical compression H of the rib unit;

[0008] s2. Calculate the welding rate ψ in the normal direction of the hypotenuse of the rib unit according to the compression amount;

[0009] s3. Compare and evaluate the compression H of the rib unit in the vertical direction, the welding rate ψ in the direction of the normal line of the rib unit's hypotenuse, and the design specification value to determine whether the product meets the qualified rate after welding;

[0010] s4. If qualified, batch processing of stacked oil coolers will be carried out according to normal process;

[0011] If it fails, the design parameters of the relevant parts of the stacked oil cooler will be adjusted, and the evaluation will be repeated according to the above steps until the product passes the welding test.

[0012] The specific implementation steps of the above steps s2 and s3 include:

[0013] (1) Use a brazing fixture to assemble the parts of the stacked oil cooler, measure the rib unit layer height of the product before welding, and obtain H1;

[0014] (2) Place the product in a vacuum brazing furnace for brazing. After brazing, measure the unit layer height of the ribs after welding to obtain H2;

[0015] (3) Calculate the vertical compression H of the rib unit: H = H1-H2;

[0016] (4) Calculate the welding rate ψ in the normal direction of the hypotenuse of the rib unit;

[0017] ψ = (H × cos α) / (S × t)

[0018] Where H is the vertical compression of the rib element,

[0019] α is the inclination angle of the rib hypotenuse,

[0020] S is the percentage of the solder coating, generally the solder coating is 15% of the solder core.

[0021] t is the thickness of the rib.

[0022] In the aforementioned step s3, the process design specifications for the vacuum brazing oil cooler are as follows:

[0023] The compression of the rib unit in the vertical direction H≤0.55t;

[0024] The welding rate of the rib unit in the normal direction of the oblique side is ≥50%.

[0025] In the aforementioned s4, the design parameters of the relevant components of the stacked oil cooler include: the inclination angle α of the rib bevel, the height A of the rib boss, the width B of the rib boss welding surface and the fin height h.

[0026] The adjustment indicators of the aforementioned rib bevel angle α, rib boss height A, rib boss welding surface width B and fin height h are:

[0027] α=80±1°;

[0028] h=H2+0.05, tolerance: (0,+0.05);

[0029] A=H1 / 2, tolerance: (0,+0.03);

[0030] B=1.6(0,+0.3).

[0031] Compared with the prior art, the present invention discloses a method for evaluating the bevel welding rate of an aluminum stacked oil cooler. First, the layer height of the rib unit before and after welding of the product is measured respectively, and the compression H of the rib unit in the vertical direction is calculated; based on the compression, the welding rate ψ in the normal direction of the bevel of the rib unit is calculated; and the compression H in the vertical direction of the rib unit, the welding rate ψ in the normal direction of the bevel of the rib unit and the design specification value are compared and evaluated to determine whether the product meets the qualified rate after welding; if qualified, the stacked oil cooler is batch processed according to the normal process; if unqualified, the design parameters of the relevant components of the stacked oil cooler are adjusted, and the evaluation is repeated according to the above steps until the product meets the qualified rate after welding. The present invention can accurately evaluate the welding rate of products, is easy to operate, and is timely. During the product processing process, this evaluation method can be used to timely adjust the design parameters of related components of the stacked oil cooler, so that the bevel welding rate of the product reaches 60% of the product requirement, thereby effectively improving the product's airtightness qualification rate, burst strength and other technical indicators. Especially in the mass production process, the qualified rate of the products can be achieved to 100%, saving the cost of product rework or scrapping, and having good economic and practicality.

[0032] Other advantages, objects, and features of the present invention will be described in part in the following description and, in part, will be apparent to those skilled in the art upon examination of the following description or may be learned from practice of the present invention. The objects and other advantages of the present invention may be realized and obtained through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be further described in detail below with reference to the accompanying drawings, in which:

[0034] Figure 1 It is a structural diagram of a stacked oil cooler;

[0035] Figure 2 for Figure 1 A partial enlarged schematic diagram of part I. DETAILED DESCRIPTION

[0036] The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the preferred embodiments are only for illustrating the present invention, and are not intended to limit the scope of protection of the present invention.

[0037] like Figure 1-Figure 2As shown, a method for evaluating the bevel welding rate of an aluminum laminated oil cooler includes the following steps:

[0038] s1. Measure the rib unit layer height before and after welding, and calculate the vertical compression H of the rib unit;

[0039] s2, according to the amount of compression, calculate the welding rate of the rib unit in the normal direction of the hypotenuse ψ;

[0040] s3. Compare and evaluate the compression H of the rib unit in the vertical direction, the welding rate ψ in the direction of the normal line of the rib unit's hypotenuse, and the design specification value to determine whether the product meets the qualified rate after welding;

[0041] s4. If qualified, batch processing of stacked oil coolers will be carried out according to normal process;

[0042] If it fails, the design parameters of the relevant parts of the stacked oil cooler will be adjusted, and the evaluation will be repeated according to the above steps until the product passes the welding test.

[0043] The specific implementation steps of steps s2 and s3 include:

[0044] (1) Use a brazing fixture to assemble the parts of the stacked oil cooler, measure the rib unit layer height of the product before welding, and obtain H1;

[0045] like Figure 1 The stacked oil cooler includes a base 1 and a cover plate 5 positioned opposite to each other, a bottom rib plate 2 is provided on the upper surface of the base 1, and a plurality of groups of stacked rib sheet units are provided between the bottom rib plate 2 and the cover plate 5, each group of rib sheet units includes two stacked rib sheets 3, and a corrugated plate 4 is provided in the cavity between the two rib sheets 3;

[0046] (2) Place the product in a vacuum brazing furnace for brazing. After brazing, measure the unit layer height of the ribs after welding to obtain H2;

[0047] (3) Based on the measured values ​​in steps (1) and (2), calculate the vertical compression H of the rib unit: H = H1-H2;

[0048] (4) Calculate the welding rate ψ in the normal direction of the hypotenuse of the rib unit:

[0049] ψ = (H × cos α) / (S × t)

[0050] Where H is the vertical compression of the rib element,

[0051] α is the inclination angle of the rib hypotenuse,

[0052] S is the percentage of the solder coating, generally the solder coating is 15% of the solder core.

[0053] t is the thickness of the rib.

[0054] In step s3, the process design specifications of the vacuum brazing oil cooler are as follows:

[0055] The compression of the rib unit in the vertical direction H≤0.55t;

[0056] The welding rate of the rib unit in the normal direction of the oblique side is ≥50%.

[0057] In said s4, the design parameters of the relevant parts of the stacked oil cooler include: the rib bevel angle α, the rib boss height A, the rib boss welding surface width B and the fin height h;

[0058] Among them, the adjustment index of each design parameter is:

[0059] α=80±1°;

[0060] h=H2+0.05, tolerance: 0,+0.05;

[0061] A=H1 / 2, tolerance: 0,+0.03;

[0062] B=1.6(0,+0.3). Example

[0063] The initial design parameters of an aluminum stacked oil cooler are: bevel angle α0 is 79 degrees, t = 0.6, S = 0.15, rib

[0064] The sheet boss height A0 is 1.41, the rib boss welding surface width B0 is 1.60 and the fin height h0 is 2.60;

[0065] The measured rib unit layer height H10 before welding is 2.82; the rib unit layer height H20 after welding is 2.55;

[0066] Calculate the vertical compression H0 of the rib element: H0 = H10-H20 = 2.82-2.55 = 0.27;

[0067] Calculate the welding rate ψ0 in the normal direction of the hypotenuse of the rib element: ψ0 = (H0 × cosα0) / (S × t) = 57%

[0068] Conduct weldability assessment:

[0069] The vertical compression of the rib unit is H≤0.55t, specifically, H0<0.55*0.6=0.33;

[0070] The welding rate of the rib unit in the normal direction of the hypotenuse is ≥50%, and ψ0>50%. The welding rate of this product has passed the evaluation.

[0071] The qualified rate is determined by non-destructive or ultrasonic testing. Example

[0072] The initial design parameters of an aluminum stacked oil cooler are: bevel angle α0 is 80 degrees, t = 0.5, S = 0.15, rib boss height A0 is 1.35, rib boss weld surface width B0 is 1.60, and fin height h0 is 2.50;

[0073] The measured rib unit layer height H10 before welding is 2.70; the rib unit layer height H20 after welding is 2.45;

[0074] Calculate the vertical compression H0 of the rib element: H0 = H10-H20 = 2.70-2.45 = 0.25;

[0075] Calculate the welding rate ψ0 in the normal direction of the hypotenuse of the rib element: ψ0 = (H0 × cosα0) / (S × t) = 58%

[0076] Conduct weldability assessment:

[0077] The compression amount of the rib unit in the vertical direction H≤0.55t, specifically, H0<0.55*0.5=0.275;

[0078] The welding rate of the rib unit in the normal direction of the hypotenuse is ≥50%, specifically, ψ0>50%. After evaluation, the welding rate of this product is qualified.

[0079] The qualified rate is determined by non-destructive or ultrasonic testing. Example

[0080] The initial design parameters of an aluminum stacked oil cooler are: bevel angle α0 is 82 degrees, t = 0.4, s = 0.15, rib boss height A0 is 0.95, rib boss weld surface width B0 is 1.60, and fin height h0 is 1.80.

[0081] The measured rib unit layer height H10 before welding is 1.90; the rib unit layer height H20 after welding is 1.75;

[0082] Calculate the vertical compression H0 of the rib element: H0 = H10-H20 = 1.90-1.75 = 0.15;

[0083] Calculate the welding rate ψ0 in the normal direction of the rib element's oblique edge: ψ0 = (H0 × cosα0) / (S × t) = 35%;

[0084] Conduct weldability assessment:

[0085] The compression amount of the rib unit in the vertical direction H≤0.55t, specifically, H0>0.55*0.4=0.22;

[0086] The welding rate of the rib unit in the normal direction of the hypotenuse is ≤50%, and ψ0 is less than 50%. The welding rate of this product fails the evaluation.

[0087] The qualified rate is tested by non-destructive or ultrasonic method and judged as unqualified.

[0088] Adjust the design parameters of related parts:

[0089] α1 = 81°;

[0090] h1 = H20 + 0.05 = 1.75;

[0091] A=H10 / 2=0.95;

[0092] B=1.6.

[0093] The product brazing process is carried out again according to the newly adjusted parameters, and the rib unit layer height H1 1 before the product welding is measured.

[0094] 1.90; the rib unit layer height H21 after welding is 1.70;

[0095] Calculate the vertical compression H1 of the rib element: H1 = H11-H21 = 1.90-1.70 = 0.2;

[0096] Calculate the welding rate ψ1 in the normal direction of the hypotenuse of the rib element: ψ1 = (H1 × cosα1) / (S × t) = 52%

[0097] Conduct weldability assessment:

[0098] The compression amount of the rib unit in the vertical direction H≤0.55t, specifically, H0<0.55*0.4=0.22;

[0099] The welding rate of the rib unit in the normal direction of the hypotenuse is ≥50%, specifically, ψ0>50%. After evaluation, the welding rate of this product is qualified.

[0100] The qualified rate is determined by non-destructive or ultrasonic testing.

[0101] It can be seen from the above-mentioned Examples 1, 2 and 3 that:

[0102] (1) The evaluation method of the present invention provides consistent results for product weldability with those obtained from nondestructive or ultrasonic testing, and can accurately evaluate the weldability of products.

[0103] (2) During the product processing, this evaluation method can be used to timely adjust the design parameters of the relevant parts of the stacked oil cooler so that the bevel welding rate of the product can meet the use requirements. Especially in the batch production process, the qualified rate of the products can reach 100%.

[0104] The above description is only a preferred embodiment of the present invention and does not constitute any form of confidentiality restriction on the present invention. Any simple modification, equivalent change and modification of the above embodiment that does not deviate from the content of the technical solution of the present invention and is based on the technical essence of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A method for evaluating the bevel welding rate of an aluminum laminated oil cooler, characterized in that: The following steps are involved: s1. Measure the rib unit layer height before and after welding, and calculate the vertical compression H of the rib unit; s2. Calculate the welding rate ψ in the normal direction of the hypotenuse of the rib unit according to the compression amount; s3. Compare and evaluate the compression H of the rib unit in the vertical direction, the welding rate ψ in the direction of the normal line of the rib unit's hypotenuse, and the design specification value to determine whether the product meets the qualified rate after welding; s4. If qualified, batch processing of stacked oil coolers will be carried out according to normal process; If it fails, adjust the design parameters of the relevant parts of the stacked oil cooler and repeat the evaluation according to the above steps until the product passes the welding test; The specific implementation steps of steps s2 and s3 include: (1) Use a brazing fixture to assemble the parts of the stacked oil cooler, measure the rib unit layer height of the product before welding, and obtain H1; (2) Place the product in a vacuum brazing furnace for brazing. After brazing, measure the unit layer height of the ribs after welding to obtain H2; (3) Calculate the vertical compression H of the rib unit: H = H1-H2; (4) Calculate the welding rate ψ in the normal direction of the hypotenuse of the rib unit: ψ = (H × cos α) / (S × t) Where H is the vertical compression of the rib element, α is the inclination angle of the rib hypotenuse, S is the percentage of the solder coating, the solder coating is 15% of the solder core, t is the thickness of the tendon; In step s4, the design parameters of the relevant components of the stacked oil cooler include: the rib bevel angle α, the rib boss height A, the rib boss welding surface width B, and the fin height h.

2. The method for evaluating the bevel welding rate of an aluminum stacked oil cooler according to claim 1, wherein: In step s3, the process design specifications of the vacuum brazing oil cooler are as follows: The compression of the rib unit in the vertical direction H≤0.55t; The welding rate of the rib unit in the normal direction of the oblique side is ≥50%.

3. The method for evaluating the bevel welding rate of an aluminum stacked oil cooler according to claim 1, wherein: The adjustment indicators of the rib bevel angle α, rib boss height A, rib boss welding surface width B and fin height h are: α=80±1 °； h=H2+0.05, tolerance: (0,+0.05); A=H1 / 2, tolerance: (0,+0.03); B＝1.6(0，+0.3)。

Images