Inertial friction welding clamping accuracy control method for large length-diameter ratio shaft / tube components

Abstract

The present invention provides a method for controlling the clamping accuracy of large length-diameter ratio shaft / tube components in inertia friction welding, including: pre-installing a hydraulic cylinder, pre-clamping the component, installing and aligning a laser rangefinder, presetting the acquisition time and performing data acquisition and pressure value adjustment, and completing automatic welding. This method can effectively solve the problems that it is difficult for manual workers to measure the radial runout value of the welding workpiece during the inertia friction welding process of large length-diameter ratio tube / shaft components, and it is difficult to ensure the coaxiality, connection strength and welding quality of the workpiece after welding; ensure that the workpiece has good coaxiality after welding, the connection strength of the welded joint is high, the weld microstructure performance is uniform, and the welding quality is guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of solid-phase welding, and particularly relates to a method for controlling the clamping accuracy of large aspect ratio shaft / tube components in inertia friction welding. Background Art

[0002] Inertia friction welding refers to a friction welding technology in which two workpieces are joined by surface contact and relative high-speed rotational friction to generate heat; it has the characteristics of high joint connection strength, high welding efficiency, and low cost, and is suitable for friction welding of the same and dissimilar material combinations such as carbon steel, aluminum alloy, magnesium alloy, cemented carbide, and superalloy, and is widely used in fields such as machinery manufacturing, petrochemical industry, automobile manufacturing, and light industry and textile industry.

[0003] The pre-welding clamping accuracy of the workpieces to be welded by inertia friction welding has a great influence on the welding quality of the welded joints. If the coaxiality of the two workpieces to be welded after clamping is poor, it will not only result in poor welding accuracy, but also cause uneven friction heat input at the welding interface, resulting in low joint strength. In addition, large aspect ratio tube / shaft components are widely used in industries such as large-scale mechanical equipment and petrochemical industry. After the large aspect ratio tube / shaft components are clamped by the inertia friction welding tooling, due to multiple factors such as machining accuracy errors of the welding tooling, wear or deformation of the tooling during long-term use, the radial runout of the large aspect ratio tube / shaft components after clamping is often very large. Especially due to the limitations of the inertia friction welding equipment structure or clamping method, etc., the cantilever is relatively long after clamping, resulting in a multiple increase in the radial runout at the welding interface of the workpieces to be welded, thereby leading to poor welding quality and low connection strength of the welded joints; at the same time, the process characteristics of inertia friction welding determine that the workpieces to be welded on the moving slide do not rotate, and it is difficult to measure the radial runout value of the workpieces to be welded after clamping by traditional dial indicators, etc., seriously affecting the welding accuracy and strength of the workpieces to be welded. Summary of the Invention

[0004] Aiming at the problems existing in the above prior art, the purpose of the present invention is to provide a method for controlling the clamping accuracy of large aspect ratio shaft / tube components in inertia friction welding, so as to solve the problems that it is difficult for manual workers to measure the radial runout value of the welding workpieces during the inertia friction welding process of large aspect ratio tube / shaft components, resulting in large radial runout of the welded parts during the welding process, and further causing poor coaxiality of the welded workpieces, uneven weld microstructure properties, poor welding quality, and poor connection strength of the welded parts.

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

[0006] A method for controlling the clamping accuracy of large aspect ratio shaft / tube components in inertia friction welding, characterized in that it includes the following steps:

[0007] Step 1: Uniformly pre-install multiple hydraulic cylinders on the moving slide of the inertia friction welding equipment to adjust and control the radial runout value of the workpiece to be welded.

[0008] Step 2: After loading the large aspect ratio pipe / axis component into the welding fixture, perform pre-clamping.

[0009] Step 3: Fix the housing of the laser rangefinder on the inertia friction welding equipment, and ensure that the emitting end of the laser rangefinder is located on the upper side of the outer circle of the welding interface of the large aspect ratio pipe / axis component, and the emitting end (receiving end) of the laser rangefinder is perpendicular to the pipe / axis component, for measuring the distance from the laser rangefinder to the surface of the large aspect ratio pipe / axis component.

[0010] Step 4: Preset the acquisition time interval Δt of the laser rangefinder, and the laser rangefinder collects data every Δt. According to the hydraulic cylinder control algorithm, adjust the pressure values of multiple hydraulic cylinders in real time.

[0011] Step 5: After the pipe / axis component installed in the welding fixture is within a reasonable radial runout range, the inertia friction welding equipment automatically completes the automatic welding of the workpiece to be welded.

[0012] For further optimization, the number of hydraulic cylinders in Step 1 is 3 - 6; the pressure range of the hydraulic cylinders is 5 - 50 kN.

[0013] For further optimization, the outer diameter of the large aspect ratio pipe / axis component in Step 2 is The exposed length of the large aspect ratio pipe / axis component after clamping is 100 - 400 mm.

[0014] For further optimization, the number of laser rangefinders in Step 3 is the same as the number of hydraulic cylinders, and the laser rangefinders are arranged corresponding to the hydraulic cylinders; the distances from each laser rangefinder to the center point of the large aspect ratio pipe / axis component are the same; the laser rangefinders are located at the end of the workpiece to be welded near the moving slide clamping.

[0015] For further optimization, the specific hydraulic cylinder control algorithm is as follows:

[0016] First, obtain the distance L between the laser rangefinder and the outer circle surface of the pipe / axis component at the current moment Δt and the distance L between the laser rangefinder and the outer circle surface of the pipe / axis component at the previous moment with an interval of one Δt Δt-1 ;

[0017] Then, obtain the difference ΔL1 between the distances at the current moment and the previous moment:

[0018] ΔL1 = |L Δt - L Δt-1 |;

[0019] After that, obtain the maximum value L of the distance between the laser rangefinder and the outer cylindrical surface of the pipe / axial component at all recorded times. max And the minimum value L min , and obtain the distance range difference ΔL2 at all times:

[0020] ΔL2 = L max - L min ;

[0021] Preset radial runout threshold: If the difference ΔL1 is within the runout threshold and the distance range difference ΔL2 is within the runout threshold, the hydraulic cylinder of the laser rangefinder is not adjusted; if the difference ΔL1 or the distance range difference ΔL2 at the current time is outside the runout threshold, adjust the pressure value of the hydraulic cylinder to achieve the control of the corresponding radial runout.

[0022] Preferably, the runout threshold is 0.08 - 0.35 mm.

[0023] For further optimization, the adjustment of the hydraulic cylinder pressure value is specifically as follows:

[0024] First, obtain the pressure value N applied at the previous time with an interval of one Δt from the current time of the hydraulic cylinder Δt-1 And the pressure value N applied at the previous time with an interval of two Δt from the current time Δt-2 , and obtain the pressure change value ΔN of the previous time:

[0025] ΔN = N Δt-1 - N Δt-2 ;

[0026] If ΔN > 0, it means that the pressure value of the hydraulic cylinder was increased at the previous time:

[0027] If the difference ΔL1 or the distance range difference ΔL2 at the current time is less than the runout threshold range, then the hydraulic cylinder corresponding to the laser rangefinder reduces the pressure value by one unit;

[0028] If the difference ΔL1 or the distance range difference ΔL2 at the current time is greater than the runout threshold range, since the pressure value of the hydraulic cylinder was increased at the previous time, considering the adjustment lag, the hydraulic cylinder is not adjusted at this time, and judge the relationship between the difference ΔL1 or the distance range difference ΔL2 at the next time and the runout threshold;

[0029] If ΔN < 0, it means that the pressure value of the hydraulic cylinder was decreased at the previous time:

[0030] When the difference ΔL1 or the distance range ΔL2 at the current moment is less than the jumping threshold range, since the pressure value of the hydraulic cylinder was decreased at the previous moment, considering the adjustment hysteresis, the hydraulic cylinder does not perform adjustment at this moment, and the relationship between the difference ΔL1 or the distance range ΔL2 and the jumping threshold at the next moment is judged;

[0031] When the difference ΔL1 or the distance range ΔL2 at the current moment is greater than the jumping threshold range, the hydraulic cylinder corresponding to the laser rangefinder increases by one unit of pressure value;

[0032] If ΔN = 0, it means that the pressure value of the hydraulic cylinder is not adjusted at the previous moment:

[0033] When the difference ΔL1 or the distance range ΔL2 at the current moment is less than the jumping threshold range, the hydraulic cylinder corresponding to the laser rangefinder decreases by one unit of pressure value;

[0034] When the difference ΔL1 or the distance range ΔL2 at the current moment is greater than the jumping threshold range, the hydraulic cylinder corresponding to the laser rangefinder increases by one unit of pressure value.

[0035] The present invention has the following technical effects:

[0036] This application uses the cooperation of a laser rangefinder and an auxiliary hydraulic cylinder. By monitoring and controlling non-rotating pipe / shaft components on the moving slide table, it solves the problems that it is difficult for manual workers to measure the radial runout value of welding workpieces during the inertia friction welding process of large aspect ratio pipe / shaft components, and it is difficult to ensure the coaxiality, connection strength and welding quality of the welded workpieces; through the monitoring and adjustment of non-rotating pipe / shaft components on the moving slide table, it avoids problems such as heat generation due to friction and difficulty in control caused by adjusting rotating workpieces during the welding process, thereby ensuring real-time and effective control of the radial runout value of components during the inertia friction welding process, ensuring good coaxiality of the welded workpieces, high connection strength of the welded joints, uniform weld tissue performance, and good welding quality.

[0037] In addition, this application realizes the sub-period evaluation and overall evaluation of the radial runout value of the welded part through the difference and distance range at the current moment, ensures the overall and sub-period monitoring of the welded part during the friction welding process, guarantees the effectiveness of monitoring and the real-time nature of adjustment, ensures the test accuracy, and reduces the test error. Description of the Drawings

[0038] Figure 1 It is a schematic structural diagram of a device for controlling the clamping accuracy of large aspect ratio shaft / pipe components in an embodiment of the present invention.

[0039] Figure 2 It is a partial enlarged view of A in the figure.

[0040] Figure 3This is a cross-sectional view of the hydraulic cylinder of the clamping accuracy control device for large aspect ratio shaft / tube components in the embodiments of the present invention.

[0041] Among them, 10 is the main spindle box; 11 is the laser rangefinder; 20 is the moving slide; 21 is the hydraulic cylinder; 30 is the first welded part; 40 is the second welded part. Specific embodiments

[0042] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments.

[0043] Embodiment 1:

[0044] As Figures 1 to 3 shown, a method for controlling the clamping accuracy of large aspect ratio shaft / tube components in inertia friction welding is characterized by including the following steps:

[0045] Step 1: Uniformly pre-install three hydraulic cylinders on the moving slide of the inertia friction welding equipment to adjust and control the radial runout value of the workpiece to be welded; the pressure range of the hydraulic cylinder is 5-50 kN;

[0046] Step 2: After loading the large aspect ratio tube component into the welding fixture, perform pre-clamping; the outer diameter of the large aspect ratio tube component is The exposed length of the large aspect ratio tube / shaft component after clamping is 100 mm.

[0047] Step 3: Fix the seat body of the laser rangefinder on the inertia friction welding equipment, and ensure that the emitting end of the laser rangefinder is located on the upper side of the outer circle of the welding interface of the large aspect ratio tube component, and the emitting end (receiving end) of the laser rangefinder is perpendicular to the tube component, for measuring the distance from the laser rangefinder to the surface of the large aspect ratio tube component;

[0048] The number of laser rangefinders is the same as the number of hydraulic cylinders (i.e., three), and the laser rangefinders are arranged corresponding to the hydraulic cylinders; the distances from each laser rangefinder to the center point of the large aspect ratio tube component are the same; the laser rangefinder is located at one end of the workpiece to be welded near the moving slide for clamping at the welding interface.

[0049] Step 4: Preset the data acquisition time interval Δt of the laser rangefinder (Δt is evenly divided according to the total time of friction welding), and the laser rangefinder acquires data every Δt. According to the hydraulic cylinder control algorithm, the pressure values of multiple hydraulic cylinders are adjusted in real time;

[0050] The specific hydraulic cylinder control algorithm is:

[0051] First, obtain the distance L between the laser rangefinder and the outer circle surface of the tube component at the current moment Δt, the distance L between the laser rangefinder and the outer circular surface of the pipe component at the previous moment with an interval of Δt Δt-1 ;

[0052] Then, obtain the difference ΔL1 between the current moment and the previous moment:

[0053] ΔL1 = |L Δt - L Δt-1 |;

[0054] After that, obtain the maximum value L max of the distances between the laser rangefinder and the outer circular surface of the pipe component within all recorded moments and the minimum value L min , and obtain the distance range ΔL2 within all moments:

[0055] ΔL2 = L max - L min ;

[0056] Preset radial runout threshold: If the difference ΔL1 is within the runout threshold and the distance range ΔL2 is within the runout threshold, the hydraulic cylinder of the laser rangefinder is not adjusted; if the difference ΔL1 or the distance range ΔL2 at the current moment is outside the runout threshold, adjust the pressure value of the hydraulic cylinder to achieve the control of the corresponding radial runout; the runout threshold is 0.08 - 0.35 mm.

[0057] The adjustment of the hydraulic cylinder pressure value is specifically as follows:

[0058] First, obtain the pressure value N Δt-1 applied by the hydraulic cylinder at the previous moment with an interval of Δt from the current moment and the pressure value N Δt-2 applied by the hydraulic cylinder at the previous moment with an interval of two Δt from the current moment, and obtain the pressure change value ΔN:

[0059] ΔN = N Δt-1 - N Δt-2 ;

[0060] If ΔN > 0, it means that the pressure value of the hydraulic cylinder was increased at the previous moment:

[0061] If the difference ΔL1 or the distance range ΔL2 at the current moment is less than the runout threshold range, then the hydraulic cylinder corresponding to the laser rangefinder reduces the pressure value by one unit;

[0062] If the difference ΔL1 or the distance range ΔL2 at the current moment is greater than the runout threshold range, since the pressure value of the hydraulic cylinder was increased at the previous moment, considering the adjustment lag, the hydraulic cylinder is not adjusted at this moment, and judge the relationship between the difference ΔL1 or the distance range ΔL2 at the next moment and the runout threshold;

[0063] If ΔN < 0, it means that the pressure value of the hydraulic cylinder was decreased at the previous moment:

[0064] When the difference ΔL1 or the distance range ΔL2 at the current moment is less than the jump threshold range, since the pressure value of the hydraulic cylinder was decreased at the previous moment, considering the adjustment lag, the hydraulic cylinder is not adjusted at this moment, and the relationship between the difference ΔL1 or the distance range ΔL2 at the next moment and the jump threshold is judged;

[0065] When the difference ΔL1 or the distance range ΔL2 at the current moment is greater than the jump threshold range, the hydraulic cylinder corresponding to the laser rangefinder increases by one unit of pressure value;

[0066] If ΔN = 0, it means that the pressure value of the hydraulic cylinder at the previous moment is not adjusted:

[0067] When the difference ΔL1 or the distance range ΔL2 at the current moment is less than the jump threshold range, the hydraulic cylinder corresponding to the laser rangefinder decreases by one unit of pressure value;

[0068] When the difference ΔL1 or the distance range ΔL2 at the current moment is greater than the jump threshold range, the hydraulic cylinder corresponding to the laser rangefinder increases by one unit of pressure value.

[0069] Step Five: After the pipe component installed in the welding fixture is within a reasonable radial runout range, the inertia friction welding equipment automatically completes the automatic welding of the workpiece to be welded;

[0070] Step Six: After welding is completed, first turn off the laser rangefinder, and then release the hydraulic cylinder; then release the clamping fixtures of the first welded part and the second welded part respectively, move the sliding table back to its original position, remove the welded part, and remove the excess welding flash.

[0071] Embodiment 2:

[0072] A method for controlling the clamping accuracy of a large aspect ratio shaft / pipe component in inertia friction welding, characterized in that it includes the following steps:

[0073] Step One: Four hydraulic cylinders are evenly pre-installed on the moving sliding table of the inertia friction welding equipment to adjust and control the radial runout value of the workpiece to be welded; the pressure range of the hydraulic cylinder is 5 - 50 kN;

[0074] Step Two: After the large aspect ratio pipe component is loaded into the welding fixture, it is pre-clamped; the outer diameter of the large aspect ratio pipe component is The exposed length of the large aspect ratio pipe component after clamping is 260 mm.

[0075] Step Three: The seat body of the laser rangefinder is fixedly installed on the inertia friction welding equipment, and it is ensured that the emitting end of the laser rangefinder is located on the upper side of the outer circle of the welding interface of the large aspect ratio pipe component, and the emitting end (receiving end) of the laser rangefinder is perpendicular to the pipe component (such as Figure 1 、Figure 2 as shown in the figure, which is used to measure the distance from the laser rangefinder to the surface of the tube-shaped component with a large length-diameter ratio;

[0076] The number of laser rangefinders is the same as the number of hydraulic cylinders (i.e., four), and the laser rangefinders are arranged corresponding to the hydraulic cylinders; the distances from each laser rangefinder to the center point of the tube-shaped component with a large length-diameter ratio are the same; the laser rangefinders are located at one end of the workpiece to be welded near the moving slide clamping of the welding interface.

[0077] Step 4: Preset the data acquisition time interval Δt of the laser rangefinder (Δt is evenly divided according to the total time of friction welding), and the laser rangefinder acquires data every Δt. According to the hydraulic cylinder control algorithm, the pressure values of multiple hydraulic cylinders are adjusted in real time;

[0078] The specific hydraulic cylinder control algorithm is as follows:

[0079] First, obtain the distance L between the laser rangefinder and the outer circular surface of the tube-shaped component at the current moment Δt and the distance L between the laser rangefinder and the outer circular surface of the tube-shaped component at the previous moment with an interval of one Δt Δt-1 ;

[0080] Then, obtain the difference ΔL1 between the current moment and the previous moment:

[0081] ΔL1 = |L Δt - L Δt-1 |;

[0082] After that, obtain the maximum value L max and the minimum value L min of the distances between the laser rangefinder and the outer circular surface of the tube-shaped component at all recorded moments, and obtain the distance range difference ΔL2 at all moments:

[0083] ΔL2 = L max - L min ;

[0084] Preset the radial runout threshold: If the difference ΔL1 is within the runout threshold and the distance range difference ΔL2 is within the runout threshold, the hydraulic cylinder of the laser rangefinder is not adjusted; if the difference ΔL1 or the distance range difference ΔL2 at the current moment is outside the runout threshold, the pressure value of the hydraulic cylinder is adjusted to achieve the control of the corresponding radial runout; the runout threshold is 0.08 - 0.35 mm.

[0085] The specific adjustment of the hydraulic cylinder pressure value is as follows:

[0086] First, obtain the pressure value N Δt-1 applied by the hydraulic cylinder at the previous moment with an interval of one Δt from the current moment Δt-2, obtain the pressure change value ΔN at the previous moment:

[0087] ΔN = N Δt-1 - N Δt-2 ;

[0088] If ΔN > 0, it indicates that the pressure value of the hydraulic cylinder has increased at the previous moment:

[0089] If the difference ΔL1 or the distance range ΔL2 at the current moment is less than the jump threshold range, the hydraulic cylinder corresponding to the laser rangefinder reduces the pressure value by one unit;

[0090] If the difference ΔL1 or the distance range ΔL2 at the current moment is greater than the jump threshold range, since the pressure value of the hydraulic cylinder has increased at the previous moment and considering the adjustment hysteresis, the hydraulic cylinder does not make adjustments at this moment and judges the relationship between the difference ΔL1 or the distance range ΔL2 at the next moment and the jump threshold;

[0091] If ΔN < 0, it indicates that the pressure value of the hydraulic cylinder has decreased at the previous moment:

[0092] If the difference ΔL1 or the distance range ΔL2 at the current moment is less than the jump threshold range, since the pressure value of the hydraulic cylinder has decreased at the previous moment and considering the adjustment hysteresis, the hydraulic cylinder does not make adjustments at this moment and judges the relationship between the difference ΔL1 or the distance range ΔL2 at the next moment and the jump threshold;

[0093] If the difference ΔL1 or the distance range ΔL2 at the current moment is greater than the jump threshold range, the hydraulic cylinder corresponding to the laser rangefinder increases the pressure value by one unit;

[0094] If ΔN = 0, it indicates that the pressure value of the hydraulic cylinder is not adjusted at the previous moment:

[0095] If the difference ΔL1 or the distance range ΔL2 at the current moment is less than the jump threshold range, the hydraulic cylinder corresponding to the laser rangefinder reduces the pressure value by one unit;

[0096] If the difference ΔL1 or the distance range ΔL2 at the current moment is greater than the jump threshold range, the hydraulic cylinder corresponding to the laser rangefinder increases the pressure value by one unit.

[0097] Step Five: After the pipe - like component installed in the welding fixture is within a reasonable radial run - out range, the inertia friction welding equipment automatically completes the automatic welding of the workpiece to be welded;

[0098] Step Six: After welding is completed, first turn off the laser rangefinder, then release the hydraulic cylinder; then release the clamping fixtures of the first welded part and the second welded part respectively, move the sliding table back to its original position, remove the welded part, and remove the excess welding flash.

[0099] Example 3:

[0100] A method for controlling the clamping accuracy of a large length - diameter ratio shaft / tube component in inertia friction welding, characterized by comprising the following steps:

[0101] Step 1: Uniformly pre - install five hydraulic cylinders on the moving slide of the inertia friction welding equipment to adjust and control the radial run - out value of the workpiece to be welded; the pressure range of the hydraulic cylinders is 5 - 50 kN;

[0102] Step 2: After loading the large length - diameter ratio shaft component into the welding fixture, perform pre - clamping; the outer diameter of the large length - diameter ratio shaft component is The exposed length of the large length - diameter ratio shaft component after clamping is 400 mm.

[0103] Step 3: Fix the base of the laser rangefinder on the inertia friction welding equipment, and ensure that the emitting end of the laser rangefinder is located on the upper side of the outer circle surface of the welding interface of the large length - diameter ratio shaft component, and the emitting end (receiving end) of the laser rangefinder is perpendicular to the shaft component, for measuring the distance from the laser rangefinder to the surface of the large length - diameter ratio shaft component;

[0104] The number of laser rangefinders is the same as the number of hydraulic cylinders (i.e., five), and the laser rangefinders are arranged corresponding to the hydraulic cylinders; the distances from each laser rangefinder to the center point of the large length - diameter ratio shaft component are the same; the laser rangefinders are located at the end of the workpiece to be welded near the moving slide for clamping at the welding interface.

[0105] Step 4: Preset the data acquisition time interval Δt of the laser rangefinder (Δt is evenly divided according to the total time of friction welding), and the laser rangefinder acquires data every Δt. According to the hydraulic cylinder control algorithm, adjust the pressure values of multiple hydraulic cylinders in real - time;

[0106] The specific hydraulic cylinder control algorithm is as follows:

[0107] First, obtain the distance L between the laser rangefinder and the outer circle surface of the shaft component at the current moment Δt and the distance L between the laser rangefinder and the outer circle surface of the shaft component at the previous moment with an interval of one Δt Δt-1 ;

[0108] Then, obtain the difference ΔL1 between the distance at the current moment and the previous moment:

[0109] ΔL1 = |L Δt - L Δt-1 |;

[0110] After that, obtain the maximum value L max and the minimum value L min of the distances between the laser rangefinder and the outer circle surface of the shaft component within all recorded moments, and obtain the distance range ΔL2 within all moments:

[0111] ΔL2 = L max -L min ;

[0112] Preset radial runout threshold: If the difference ΔL1 is within the runout threshold and the distance range difference ΔL2 is within the runout threshold, the hydraulic cylinder of the laser rangefinder is not adjusted; if the difference ΔL1 or the distance range difference ΔL2 at the current moment is outside the runout threshold, the pressure value of the hydraulic cylinder is adjusted to achieve the control of the corresponding radial runout; the runout threshold is 0.08 - 0.35 mm.

[0113] The adjustment of the hydraulic cylinder pressure value is specifically as follows:

[0114] First, obtain the pressure value N applied at the previous moment with an interval of one Δt from the current moment of the hydraulic cylinder Δt-1 and the pressure value N applied at the previous moment with an interval of two Δt from the current moment Δt-2 , and obtain the pressure change value ΔN of the previous moment:

[0115] ΔN = N Δt-1 -N Δt-2 ;

[0116] If ΔN > 0, it means that the pressure value of the hydraulic cylinder was increased at the previous moment:

[0117] If the difference ΔL1 or the distance range difference ΔL2 at the current moment is less than the runout threshold range, the hydraulic cylinder corresponding to the laser rangefinder reduces the pressure value by one unit;

[0118] If the difference ΔL1 or the distance range difference ΔL2 at the current moment is greater than the runout threshold range, since the pressure value of the hydraulic cylinder was increased at the previous moment and considering the adjustment lag, the hydraulic cylinder is not adjusted at this moment, and the relationship between the difference ΔL1 or the distance range difference ΔL2 at the next moment and the runout threshold is judged;

[0119] If ΔN < 0, it means that the pressure value of the hydraulic cylinder was decreased at the previous moment:

[0120] If the difference ΔL1 or the distance range difference ΔL2 at the current moment is less than the runout threshold range, since the pressure value of the hydraulic cylinder was decreased at the previous moment and considering the adjustment lag, the hydraulic cylinder is not adjusted at this moment, and the relationship between the difference ΔL1 or the distance range difference ΔL2 at the next moment and the runout threshold is judged;

[0121] If the difference ΔL1 or the distance range difference ΔL2 at the current moment is greater than the runout threshold range, the hydraulic cylinder corresponding to the laser rangefinder increases the pressure value by one unit;

[0122] If ΔN = 0, it means that the pressure value of the hydraulic cylinder was not adjusted at the previous moment:

[0123] When the difference ΔL1 or the distance range ΔL2 at the current moment is less than the jump threshold range, the hydraulic cylinder corresponding to the laser rangefinder reduces the pressure value by one unit;

[0124] When the difference ΔL1 or the distance range ΔL2 at the current moment is greater than the jump threshold range, the hydraulic cylinder corresponding to the laser rangefinder increases the pressure value by one unit.

[0125] Step Five: After the shaft component installed in the welding fixture is within a reasonable radial runout range, the inertia friction welding equipment automatically completes the automatic welding of the workpiece to be welded;

[0126] Step Six: After welding is completed, first turn off the laser rangefinder, then release the hydraulic cylinder; then release the clamping fixtures of the first and second workpieces respectively, move the sliding table back to its original position, remove the welded part, and remove the excess welding flash.

[0127] For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present invention. Any reference signs in the claims should not be regarded as limiting the claims involved. In addition, it should be understood that although this specification is described according to embodiments, not every embodiment only contains an independent technical solution. The narrative way of this specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A method for controlling the clamping accuracy of large length-diameter ratio shaft / tube components in inertia friction welding, characterized in that: It includes the following steps: Step 1: Uniformly pre-install multiple hydraulic cylinders on the moving slide of the inertia friction welding equipment; Step 2: After loading the large aspect ratio pipe / shaft component into the welding fixture, perform pre-clamping; Step 3: Fix and install the body of the laser rangefinder on the inertia friction welding equipment, and ensure that the emitting end of the laser rangefinder is located on the upper side of the outer circle of the welding interface of the large aspect ratio pipe / shaft component, and the emitting end of the laser rangefinder is perpendicular to the pipe / shaft component; Step 4: Preset the data acquisition time interval of the laser rangefinder Δt and collect data by the laser rangefinder every Δt time. According to the hydraulic cylinder control algorithm, adjust the pressure values of multiple hydraulic cylinders in real time; Step 5: After the pipe / shaft component installed in the welding fixture is within a reasonable radial runout range, the inertia friction welding equipment automatically completes the automatic welding of the workpiece to be welded; The specific hydraulic cylinder control algorithm is: First, obtain the distance between the laser rangefinder and the outer circular surface of the pipe / axis component at the current moment , and the distance between the laser rangefinder and the outer circular surface of the pipe / axis component at the previous moment separated by a Δt ; ; Then, obtain the difference between the distance at the current moment and the previous moment ΔL 1: ； After that, obtain the maximum value of the distances between the laser rangefinder and the outer circular surface of the pipe / axial component at all recorded moments L max and the minimum value L min , and obtain the range of distances at all moments ΔL 2: ； Preset radial runout threshold: If the difference ΔL 1 is within the runout threshold and the distance range ΔL 2 is within the runout threshold, the hydraulic cylinder of the laser rangefinder is not adjusted; If the difference at the current moment ΔL 1 or the distance range ΔL 2 is outside the runout threshold, the pressure value of the hydraulic cylinder is adjusted to achieve the control of the corresponding radial runout; The specific adjustment of the hydraulic cylinder pressure value is: First, obtain the pressure value applied at the previous moment that is one Δt interval before the current moment of the hydraulic cylinder and the pressure value applied at the previous moment that is two Δt intervals before the current moment , and obtain the pressure change value at the previous moment ΔN : ； If , it means that the pressure value of the hydraulic cylinder was increased at the previous moment: If the difference at the current moment ΔL is 1 or the distance range ΔL is less than the jump threshold range, the hydraulic cylinder corresponding to the laser rangefinder reduces the pressure value by one unit; If the difference at the current moment ΔL 1 or the distance range ΔL When 2 is greater than the jump threshold range, since the pressure value of the hydraulic cylinder was increased at the previous moment, considering the adjustment lag, the hydraulic cylinder is not adjusted at this moment and the difference at the next moment is judged Δ L 1 or the distance range ΔL 2 and the relationship with the jump threshold; If , it means that the pressure value of the hydraulic cylinder was decreased at the previous moment: If the difference at the current moment ΔL 1 or the range of distance ΔL 2 is less than the jump threshold range, since the pressure value of the hydraulic cylinder was decreased at the previous moment, considering the adjustment hysteresis, the hydraulic cylinder does not perform adjustment at this moment and judges the difference at the next moment Δ L 1 or the range of distance ΔL 2 and the relationship with the jump threshold; If the difference at the current moment ΔL is 1 or the distance range ΔL is greater than the jump threshold range, the hydraulic cylinder corresponding to the laser rangefinder increases a unit of pressure value; If , it means that the pressure value of the hydraulic cylinder at the previous moment is not adjusted: If the difference at the current moment ΔL is 1 or the distance range ΔL is less than the jump threshold range, the hydraulic cylinder corresponding to the laser rangefinder reduces the pressure value by one unit; If the difference at the current moment ΔL is 1 or the distance range ΔL is greater than the jump threshold range, the hydraulic cylinder corresponding to the laser rangefinder increases by one unit of pressure value.

2. A clamping accuracy control method for large aspect ratio shaft / tube components by inertia friction welding according to claim 1, characterized in that: In the first step, the number of hydraulic cylinders is 3 to 6; the pressure range of the hydraulic cylinders is 5 to 50 kN.

3. A method for controlling the clamping accuracy of a large length-diameter ratio shaft / tube component by inertia friction welding according to claim 1 or 2, characterized in that: The number of laser rangefinders in the third step is the same as the number of hydraulic cylinders, and the laser rangefinders are arranged corresponding to the hydraulic cylinders; the distances from each laser rangefinder to the center point of the large aspect ratio pipe / shaft component are the same; the laser rangefinders are located at one end of the workpiece to be welded close to the clamping on the moving slide.

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