CN109799020A - It is a kind of can manufacture on-the-spot test welding residual stress method - Google Patents
It is a kind of can manufacture on-the-spot test welding residual stress method Download PDFInfo
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- CN109799020A CN109799020A CN201910120948.3A CN201910120948A CN109799020A CN 109799020 A CN109799020 A CN 109799020A CN 201910120948 A CN201910120948 A CN 201910120948A CN 109799020 A CN109799020 A CN 109799020A
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Abstract
The present invention provides one kind can be in the method for manufacture on-the-spot test welding residual stress, including welding processing welding point small sample, simultaneously Welded Joints small sample drills selected residual stress test point, initial displacement measurement before heat treatment, the heat treatment of postwelding stress-removal, displacement measurement after heat treatment, by comparing the displacement after drilling before heat treatment, measurement obtains the deformation of heat treatment front and back bore position, the residual stress of bore position is calculated by the deformation of bore position, it is calculated to obtain the welding residual stress of manufacture scene practical structures to be measured by the residual stress of bore position.The present invention can make full use of the convenience of manufactory, it can be realized at manufacture scene and residual stress test is carried out to welded specimen, it is compared compared with conventional method, it can effectively avoid the waste of the materials such as foil gauge, remove the trouble for pasting the operations such as strain from, compared with neutron diffraction test material internal residual stress, operating procedure is greatly simplified, and test is convenient, it is low in cost.
Description
Technical field
The present invention relates to residual stress test technical fields, and in particular to one kind can be remaining in manufacture on-the-spot test welding
The method of stress.
Background technique
Welding is that the important processing technology of one of manufacturing is being welded due to the instantaneous heat input of its high concentration
Sizable welding residual stress will be generated after connecing.Welding residual stress can seriously affect manufacturing process itself with it is welded
Service performance.Therefore, accurately test welding residual stress to prediction and eliminates the welding residual stress of practical structures with important
Meaning.
The test method of welding residual stress can be divided into mechanical measurement method and physical measurement method.Mechanical measurement method is to develop most
Early, the most commonly used residual stress test method of field application range, it is locally detached or is cut with certain method
It cuts, so that residual stress be made locally to be discharged, the deformation of measurement segmentation front and back, then applied elasticity knowledge finds out remnants
Stress.Common mechanical measurement method has borehole strain method, ring cutting method etc..But these methods need to paste foil gauge, and can only survey
The residual stress size in scale face or section.In order to understand the residual stress distribution of inside configuration in detail, finite element is generallyd use
It is studied with the method that test combines.Specially small sample is welded using welding procedure identical with big structure first
It connects, the residual stress distribution of simple welded specimen is tested using test method, then using the simulation letter of thermo-elasto-plasticity constitutive model
Single plate welding sample residual stress distribution, and compared and analyzed with test result, to verify Finite Element Method just
True property, finally, the finite element method for simulating using verifying analyzes its corresponding big structure residual stress distribution.
Mainly there are boring method, X-ray, indentation method, neutron for the residual stress test method of small-sized welded specimen at present
Diffraction approach etc., boring method and indentation method need to be test method that is a kind of not only expensive but also expending material using foil gauge, and X is penetrated
Although line and neutron diffraction do not need to expend material, but its test equipment is huge, testing procedure is complex and costly.
Therefore, it is necessary to develop a kind of suitable low in cost, simple residual stress test method of test.Currently, weldering
Residual stress test is not all carried out before product export after having connect.In order to provide the user with reliable data, need manufacturing
Factory completes a series of residual stress test, if can be answered while manufacturing product welding remnants using manufacture existence conditions
Power, which carries out test, will greatly facilitate test step.
Summary of the invention
In view of the above-mentioned problems in the prior art, the present invention makes full use of the convenience of manufactory, provides a kind of operation side
Just, method that is low in cost, residual stress test being carried out to welded specimen in the realization of manufacture scene.
The following technical solution is employed by the present invention:
It is a kind of can manufacture on-the-spot test welding residual stress method, comprising the following steps:
(1) welding processing welding point small sample:
According to the welding procedure welding processing welding point small sample of manufacture scene practical structures to be measured, the welding point
The plate thickness of small sample is consistent with the plate thickness of manufacture scene practical structures to be measured, and welding point small sample is fixed, and guarantee connects
Head small sample and welding road number, the number of plies and the welding current of per pass, voltage, the speed of welding for manufacturing scene practical structures to be measured are equal
Unanimously；
(2) it selectes residual stress test point and Welded Joints small sample drills:
Arrangement residual stress test point is required according to live residual stress test is manufactured, is being welded according to residual stress test point
Bore position is arranged in the corresponding position of connector small sample, after connector small sample to be welded is cooled to room temperature, using electrical drilling machine
It drills to selected bore position, drilling depth is according to residual stress test point in the plate thickness direction of welding point small sample
Position depending on；
(3) the initial displacement measurement before being heat-treated:
After drilling, using coordinate measuring machine, using the Weld pipe mill of welding point small sample as origin, the initial displacement of device to hole
It measures, the displacement before heat treatment in the x-direction is denoted as xi, it is heat-treated preceding displacement in the y-direction and is denoted as yi；
The direction x is the direction perpendicular to weld seam, and the direction y is the direction for being parallel to weld seam；
(4) postwelding stress-removal is heat-treated:
Welding point small sample is warming up to heat treatment temperature according to certain heating rate in heat-treatment furnace, by regulation
The heat treatment soaking time of material is kept the temperature, and is then cooled to room temperature according to certain cooling rate；
(5) displacement measurement after being heat-treated:
Welding point small sample after heat treatment is removed into heat-treatment furnace, after cooling, equally uses coordinate measuring machine, with
Sample Weld pipe mill is origin, and the displacement of device to hole re-starts measurement, by after heat treatment in the x-direction (perpendicular to the side of weld seam
To) displacement be denoted as xf, the displacement in (direction for being parallel to weld seam) in the y-direction after heat treatment is denoted as yf；
(6) by comparing the displacement after drilling before heat treatment, measurement obtains the deformation feelings of heat treatment front and back bore position
Condition:
Deformation in the direction x (perpendicular to the direction of weld seam) and the direction y (direction for being parallel to weld seam) passes through as follows respectively
Formula (1) and formula (2) calculate:
In formula, εxAnd εyRespectively indicate the deformation on the direction x and y；
xiIndicate the preceding displacement in the x-direction of heat treatment, xfIndicate the displacement after being heat-treated in the x-direction, yiBefore indicating heat treatment
Displacement in the y-direction, yfIndicate the displacement after being heat-treated in the y-direction；
(7) residual stress of bore position is calculated by the deformation of bore position:
Bore position is in the x-direction (perpendicular to the direction of weld seam) and the residual stress in the direction y (direction for being parallel to weld seam)
It is calculated respectively by following formula (3) and formula (4):
σxAnd σyRespectively indicate the stress on the direction x and y；E and υ respectively indicate elasticity modulus and Poisson's ratio；
It can be calculated to obtain the welding residual stress of manufacture scene practical structures to be measured by the residual stress of bore position.
Preferably, the bore diameter to drill in step (2) is 1~3mm.
Preferably, heating rate, heat treatment temperature, soaking time, the cooling rate of post weld heat treatment pass through in step (4)
Query criteria obtains.
The invention has the advantages that:
It is easy to operate, low in cost, can be realized pair at manufacture scene 1. can make full use of the convenience of manufactory
Welded specimen carries out residual stress test.
2. comparing compared with conventional method, the waste of the materials such as foil gauge can effectively avoid, remove the fiber crops for pasting the operations such as strain from
It is tired.
3. the present invention can residual stress distribution inside test splice, with neutron diffraction test material internal residual stress phase
Than operating procedure greatly simplifies, and convenient test.
Detailed description of the invention
Fig. 1 is heat treatment cycle curve；
Fig. 2 is deformation test schematic diagram.
Wherein, 1 is weld seam；2 be drilling；3 be sample after heat treatment；4 be sample before heat treatment；△ X is perpendicular to weld seam
Direction displacement variable；△ Y is the displacement variable for being parallel to the direction of weld seam.
Specific embodiment
The present invention is specifically described with reference to the accompanying drawing:
One kind can be in the method for manufacture on-the-spot test welding residual stress combined with Figure 1 and Figure 2, comprising the following steps:
(1) welding processing welding point small sample:
According to the welding procedure welding processing welding point small sample of manufacture scene practical structures to be measured, the welding point
The plate thickness of small sample is consistent with the plate thickness of manufacture scene practical structures to be measured, and welding point small sample is fixed, and guarantee connects
Head small sample and welding road number, the number of plies and the welding current of per pass, voltage, the speed of welding for manufacturing scene practical structures to be measured are equal
Unanimously；
(2) it selectes residual stress test point and Welded Joints small sample drills:
Arrangement residual stress test point is required according to live residual stress test is manufactured, is being welded according to residual stress test point
Bore position is arranged in the corresponding position of connector small sample, after connector small sample to be welded is cooled to room temperature, using electrical drilling machine
It drills to selected bore position, bore diameter is 1~3mm, and drilling depth connects according to residual stress test point in welding
Depending on the position in the plate thickness direction of head small sample；Drilling depth is accurately controlled by the fixed device of drill bit, when drill bit not still further below
When mobile, electrical drilling machine is closed.
(3) the initial displacement measurement before being heat-treated:
After drilling, using coordinate measuring machine, using the Weld pipe mill of welding point small sample as origin, the initial displacement of device to hole
It measures, the displacement before heat treatment in the x-direction is denoted as xi, it is heat-treated preceding displacement in the y-direction and is denoted as yi；
The direction x is the direction perpendicular to weld seam, and the direction y is the direction for being parallel to weld seam；
(4) postwelding stress-removal is heat-treated:
Welding point small sample is warming up to heat treatment temperature according to certain heating rate in heat-treatment furnace, by regulation
The heat treatment soaking time of material is kept the temperature, and is then cooled to room temperature according to certain cooling rate；The liter of post weld heat treatment
Warm rate, heat treatment temperature, soaking time, cooling rate are obtained by query criteria.
(5) displacement measurement after being heat-treated:
Welding point small sample after heat treatment is removed into heat-treatment furnace, after cooling, equally uses coordinate measuring machine, with
Sample Weld pipe mill is origin, and the displacement of device to hole re-starts measurement, by after heat treatment in the x-direction (perpendicular to the side of weld seam
To) displacement be denoted as xf, the displacement in (direction for being parallel to weld seam) in the y-direction after heat treatment is denoted as yf；
(6) by comparing the displacement after drilling before heat treatment, measurement obtains the deformation feelings of heat treatment front and back bore position
Condition:
Deformation in the direction x (perpendicular to the direction of weld seam) and the direction y (direction for being parallel to weld seam) passes through as follows respectively
Formula (1) and formula (2) calculate:
In formula, εxAnd εyRespectively indicate the deformation on the direction x and y；
xiIndicate the preceding displacement in the x-direction of heat treatment, xfIndicate the displacement after being heat-treated in the x-direction, yiBefore indicating heat treatment
Displacement in the y-direction, yfIndicate the displacement after being heat-treated in the y-direction；
(7) residual stress of bore position is calculated by the deformation of bore position:
Bore position is in the x-direction (perpendicular to the direction of weld seam) and the residual stress in the direction y (direction for being parallel to weld seam)
It is calculated respectively by following formula (3) and formula (4):
σxAnd σyRespectively indicate the stress on the direction x and y；E and υ respectively indicate elasticity modulus and Poisson's ratio；
It can be calculated to obtain the welding residual stress of manufacture scene practical structures to be measured by the residual stress of bore position.
Embodiment 1
The welded joint structure of use are as follows: manual electric arc welding, specimen size length × width × height: 200 × 200 × 20mm, material
Material is Q345B, double V-groove.Heat treatment process employed in the method for the present invention is as shown in Figure 2.
It is shown in Table 1 apart from case depth for the residual stress size at 4mm.
Table 1 is apart from the residual stress that case depth is at 4mm
Embodiment 2
The welded joint structure of use are as follows: manual electric arc welding, specimen size length × width × height: 200 × 200 × 30mm, material
Material is 304 stainless steels, X-type groove.Heat treatment process employed in the method for the present invention is as shown in Figure 2.
It is shown in Table 2 apart from case depth for the residual stress size at 5mm.
Table 2 is apart from the residual stress that case depth is at 5mm
Certainly, the above description is not a limitation of the present invention, and the present invention is also not limited to the example above, this technology neck
The variations, modifications, additions or substitutions that the technical staff in domain is made within the essential scope of the present invention also should belong to of the invention
Protection scope.
Claims (3)
1. one kind can be in the method for manufacture on-the-spot test welding residual stress, which comprises the following steps:
(1) welding processing welding point small sample:
According to the welding procedure welding processing welding point small sample of manufacture scene practical structures to be measured, the welding point lab scale
The plate thickness of sample is consistent with the plate thickness of manufacture scene practical structures to be measured, and welding point small sample is fixed, and guarantees that welding point is small
Sample and welding road number, the number of plies and the welding current of per pass, voltage, the speed of welding for manufacturing scene practical structures to be measured are uniform
It causes；
(2) it selectes residual stress test point and Welded Joints small sample drills:
Arrangement residual stress test point is required according to live residual stress test is manufactured, is connect according to residual stress test point in welding
Bore position is arranged in the corresponding position of head small sample, after connector small sample to be welded is cooled to room temperature, using electrical drilling machine to choosing
Fixed bore position drills, position of the drilling depth foundation residual stress test point in the plate thickness direction of welding point small sample
Depending on setting；
(3) the initial displacement measurement before being heat-treated:
After drilling, using coordinate measuring machine, using the Weld pipe mill of welding point small sample as origin, the initial displacement of device to hole is carried out
Displacement before heat treatment in the x-direction is denoted as x by measurementi, it is heat-treated preceding displacement in the y-direction and is denoted as yi；
The direction x is the direction perpendicular to weld seam, and the direction y is the direction for being parallel to weld seam；
(4) postwelding stress-removal is heat-treated:
Welding point small sample is warming up to heat treatment temperature according to certain heating rate in heat-treatment furnace, by prescribed material
Heat treatment soaking time kept the temperature, be then cooled to room temperature according to certain cooling rate；
(5) displacement measurement after being heat-treated:
Welding point small sample after heat treatment is removed into heat-treatment furnace, after cooling, uses coordinate measuring machine, equally with sample
Weld pipe mill is origin, and the displacement of device to hole re-starts measurement, and the displacement in the x-direction after heat treatment is denoted as xf, in the y-direction
Displacement be denoted as yf；
(6) by comparing the displacement after drilling before heat treatment, measurement obtains the deformation of heat treatment front and back bore position:
Deformation in the direction x and the direction y passes through following formula (1) respectively and formula (2) calculates:
In formula, εxAnd εyRespectively indicate the deformation on the direction x and y；
(7) residual stress of bore position is calculated by the deformation of bore position:
Bore position passes through following formula (3) respectively with the residual stress in the direction y in the x-direction and formula (4) calculates:
σxAnd σyRespectively indicate the stress on the direction x and y；E and υ respectively indicate elasticity modulus and Poisson's ratio；
It can be calculated to obtain the welding residual stress of manufacture scene practical structures to be measured by the residual stress of bore position.
2. one kind according to claim 1 can be in the method for manufacture on-the-spot test welding residual stress, which is characterized in that
The bore diameter to drill in step (2) is 1~3mm.
3. one kind according to claim 1 can be in the method for manufacture on-the-spot test welding residual stress, which is characterized in that
The heating rate, heat treatment temperature, soaking time, cooling rate of post weld heat treatment are obtained by query criteria in step (4).
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN114295260A (en) * | 2021-12-29 | 2022-04-08 | 福建省锅炉压力容器检验研究院 | Welding seam residual stress reliability simulation testing device |
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| CN109799020B (en) | 2020-11-13 |
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