The shape bending blank-making method of nickel base superalloy flash welding thin-walled ring
Technical field
The present invention relates to a kind of bending method of section bar, particularly relate to the shape bending blank-making method of nickel base superalloy flash welding thin-walled ring.
Background technology
Along with the industries such as Aeronautics and Astronautics, boats and ships, gas turbine, wind energy, nuclear energy and bearing are to the increase of ring demand, the ring adopting traditional milling method to be shaped is because machine-finish allowance is large, stock utilization is low, not only waste a large amount of materials, but also the cost of ring is remained high.And adopting the ring of Flash Butt Welding explained hereafter, it is few that machine adds surplus, and stock utilization is high, and cost also reduces thereupon greatly, is conducive to ring is shaped towards Precision Forming Technology future development.The technology of preparing of flash of light weld-ring base is one of key technology of producing flash welding ring.
In prior art, mainly following methods is adopted for the preparation of flash of light weld-ring base: first loaded by section bar on bending machine and bend to approximate circle, and respectively stay one section of straight flange at section bar two ends position; On the type machine of school, the straight portion of section bar and circular arc portion are bent to a knuckle again, the straight flange at section bar two ends is alignd mutually, being convenient to flash butt welder to the clamping of ring base welds.The flash of light weld-ring base adopting said method to prepare, can produce knuckle at the circular arc portion of ring base and the junction of two ends straight portion, easily produce impression on the surface of ring base; Described ring base is configured as after ring through flash welding, need to carry out the circle process of bulging school, during bulging knuckle place easily produce stress concentrate caused ring to be scrapped by spalling, school bowlder, cost a large amount of man-hour and energy consumption is needed to repair knuckle, and can not be completely eliminated, after the circle of school, the overall ovality of ring is larger; Because the allowance of flash welding ring is less, there is the dimensional accuracy that impression all can affect ring in the comparatively large and surface of ring ovality, causes dimensional accuracy low, be unfavorable for obtaining few flash welding ring of processing without surplus.
Summary of the invention
The technical problem to be solved in the present invention is to provide a kind ofly carries out method that segmentation bends to realize the bending base of nickel base superalloy flash welding thin-walled ring section bar to section bar on bending machine, the knuckle that the method produces when can eliminate bending nickel base superalloy section bar and impression, be conducive to improving flash welding ring dimensional accuracy and crudy.
For solving the problems of the technologies described above, the shape bending blank-making method of nickel base superalloy flash welding thin-walled ring of the present invention, its technical scheme comprises the following steps:
Nickel base superalloy section bar by specification blanking is divided into mn, no, op, pq and qw five sections, and the ratio of described each section is
mn:
no:
op:
pq:
qw=
1.0:
2.0 ~ 2.5:
7.0 ~ 8.0:
2.0 ~ 2.5:
1.0, more described section bar is heated to 650 DEG C ± 20 DEG C;
Described section bar is put into bending machine, is positioned, alignd with the center of described top roll in the center of described section bar by the top roll of bending machine and two lower rolls to it, described top roll and two lower rolls are positioned at the op section of described section bar;
Manipulate that described top roll rotates in the counterclockwise direction, two lower rolls are rotated in a clockwise direction, section bar is driven to move to its right-hand member direction, its top die mould material that moves up is made to the power of two lower rolls loading 292KN simultaneously, when the o point cantact of lower-left roller and section bar, change the direction of rotation of top roll and two lower rolls, drive section bar to move to its left end direction; When the p point cantact of bottom right roller and section bar, change the direction of rotation of top roll and two lower rolls again, drive section bar to move to its right-hand member direction, until the middle point cantact of top roll and section bar op section; In BENDING PROCESS, two lower rolls move up all the time always and push up die mould material; The linear velocity of described upper and lower roll is 2400mm/min, and the speed that described two lower rolls move up is 6.0mm/min; Repeat aforesaid operations 5 times, now, op arc section reaches predetermined radius of curvature;
Shut down the temperature detecting described section bar, if continue bending operation when being more than or equal to 450 DEG C, if be less than 450 DEG C, melt down after being heated to 650 DEG C ± 20 DEG C and continue bending no section again;
The no section of described section bar is positioned on bending machine makes its mid point align with the center of top roll; Manipulation top roll is rotated in a clockwise direction, two lower rolls rotate in the counterclockwise direction, drives section bar to move to its left end direction, makes its top die mould material that moves up to the power of two lower rolls loading 426KN simultaneously; When the o point cantact of bottom right roller and section bar, change the direction of rotation of top roll and two lower rolls, drive section bar to move to its right-hand member direction; When the n point cantact of lower-left roller and section bar, change the direction of rotation of top roll and two lower rolls again, drive section bar to move to its left end direction, until top roll contacts with the mid point of the no section of section bar; In BENDING PROCESS, two lower rolls move up all the time always and push up die mould material; The linear velocity of described upper and lower roll is 1200mm/min, and the speed that described two lower rolls move up is 7.6mm/min; Repeat aforesaid operations 5 times, now, no arc section reaches predetermined radius of curvature;
Pq section is bent by the step of above-mentioned bending no section, until the pq arc section after bending reaches predetermined radius of curvature, the mn section of described section bar and the alignment of qw section.
Preferably, the radius of curvature of described each bending arc section is determined by following formula:
In formula:
R---the radius of curvature (mm) of corresponding circle segmental arc after bending;
A---the centre distance (mm) between two lower rolls;
δ---the distance (mm) that during bending corresponding circle segmental arc, lower roll rises;
The radius (mm) of r---lower roll;
The thickness (mm) of d---section bar.
Preferably, the linear velocity of the speed that moves up of described lower roll and described upper and lower roll is determined by following formula:
In formula:
V
2---the speed (mm/min) that during bending corresponding circle segmental arc, lower roll moves up;
V
1---the linear velocity (mm/min) of top roll or lower roll during bending corresponding circle segmental arc;
R---the radius of curvature (mm) of corresponding circle segmental arc after bending;
δ---the distance (mm) that during bending corresponding circle segmental arc, lower roll rises;
The number of times (secondary) of n---corresponding circle segmental arc repeated flex.
Preferably, described bending machine loads and is determined by following formula to can the move up minimum force of top die mould material of lower roll:
In formula:
F---bending machine loads the minimum force (N) of the top die mould material that can to move up to lower roll;
The rigidity of EJ---bar, wherein, the cross section moments of inertia (cm of E to be elastic modelling quantity (GPa), J be bar
4);
A---the centre distance (mm) between two lower rolls;
The distance (mm) that δ---lower roll moves up.
Preferably, described nickel base superalloy is GH4169.
Preferably, the axial cross section size of described ring is maximum is 65mm × 30mm.
Adopt the ring base of the flash welding thin-walled ring of described method bending forming in " D " font, be made up of two straight flanges, arc sections and the excessive arc section that connects described straight flange and arc sections, the position that end is relative between two straight flanges has opening.
Compared with prior art, beneficial effect of the present invention is as follows:
The shape bending blank-making method of nickel base superalloy flash welding thin-walled ring of the present invention, in BENDING PROCESS, described section bar is divided into mn, no, op, pq and qw five sections, the ratio of described each section is
mn:
no:
op:
pq:
qw=
1.0:
2.0 ~ 2.5:
7.0 ~ 8.0:
2.0 ~ 2.5:
1.0, make the radius of curvature of bending rear op section be greater than the radius of curvature of no or pq section, the ring base being conducive to flexural deformation and obtaining in " D " font.And two straight flanges of ring base are connected by transition circle segmental arc with arc sections after bending, the connection eliminating two straight flanges and arc sections produces knuckle and produces the phenomenon of impression on ring base surface, not only make base process be easy to carry out, and the flash welding ring avoiding welding forming easily produce the problem that stress is concentrated and spalling causes ring to be scrapped in knuckle place in the sired results skill of follow-up bulging school; Meanwhile, also make bulging school circle process be easy to carry out, a large amount of man-hours and energy consumption can be saved, eliminate ovality, improve dimensional accuracy and the crudy of ring, obtain few flash welding ring without surplus processing.
In described shape bending process, when the radius of curvature of each bending arc section meets
the linear velocity of the speed that lower roll moves up and top roll, lower roll meets
time, smooth rounding off and bending forming between each bending arc section can be made.
Accompanying drawing explanation
Below in conjunction with the drawings and specific embodiments, the present invention is described in further detail.
Fig. 1 is the ring base schematic diagram of the flash welding thin-walled ring adopting prior art to produce.
Fig. 2 is the structural representation of bending machine.
Fig. 3 is the stepwise schematic views of nickel base superalloy section bar.
Fig. 4 is the installation schematic diagram of nickel base superalloy section bar.
Fig. 5 is the BENDING PROCESS schematic diagram of nickel base superalloy section bar op section.
Fig. 6 is the BENDING PROCESS schematic diagram of nickel base superalloy section bar no section.
Fig. 7 is the view after nickel base superalloy shape bending terminates.
Fig. 8 is the ring base schematic diagram of the nickel base superalloy flash welding thin-walled ring adopting the present invention to produce.
Detailed description of the invention
The shape bending blank-making method implementing nickel base superalloy flash welding thin-walled ring of the present invention needs to provide the equipment such as profile bender, heating furnace, manipulator.
Fig. 1 shows the schematic diagram of the ring base 10 of the nickel base superalloy flash welding thin-walled ring adopting prior art to produce, this ring base 10 is made up of two straight flanges 11 and arc sections 13, there is opening 14 between two straight flanges, form knuckle 12 in the junction of two straight flanges 11 respectively and between arc sections 13.
Fig. 2 shows the schematic diagram of bending machine, described bending machine 1 has top roll 2 and two lower rolls 3, described top roll 2 is installed on bearing 5, described two lower rolls 3 are contained in respectively on two cranks 4 and also can move up and down, and described top roll 2 and two lower roll 3 distributions triangular in shape also can be rotated clockwise or counterclockwise; This bending machine 1 also has the control device that the velocity of rotation of adjusting upper roll 2, two lower rolls 3 and two lower rolls 3 move up and down speed; The radius of described top roll 2 and two lower rolls 3 is 200mm, and the centre distance of two lower rolls 3 is 450mm.
The nickel base superalloy being GH4169 for China's material trademark below describes the detailed description of the invention of the shape bending blank-making method of nickel base superalloy flash welding thin-walled ring of the present invention in detail:
The main chemical elements content (percentage by weight) of this alloy is: C content≤0.08%, containing Cr amount 17.0% ~ 21.0%, ni content 50.0% ~ 55.0%, containing Co amount≤1.0%, containing Mo amount 2.80% ~ 3.30%, containing Al amount 0.30% ~ 0.70%, containing Ti amount 0.75% ~ 1.15%, containing Nb amount 4.75% ~ 5.50%, containing B amount≤0.006%, containing Mg amount≤0.01%, containing Mn amount≤0.35%, si content≤0.35%, P content≤0.015%, containing S amount≤0.015%, containing Cu amount≤0.30%, containing Ca amount≤0.01%, containing Pb amount≤0.0005%, containing Se amount≤0.0003%, surplus is Fe.
The processing step of concrete bending base is as follows:
Step 1: blanking.As shown in Figure 3, be that rectangular GH4169 alloy material is cutting into section bar 20 by specification cross section, the length of this section bar 20 is determined according to the diameter dimension of welding ring, and its maximum secting area is 65mm (width) × 30mm (thickness).This section bar 20 is divided into mn, no, op, pq and qw five sections by m, n, o, p, q, w, and for making the radius of curvature that the radius of curvature of bending rear op section is greater than no or pq section and the ring base obtained in " D " font, the ratio of each section is
mn:
no:
op:
pq:
qw=
1.0:
2.0 ~ 2.5:
7.0 ~ 8.0:
2.0 ~ 2.5:
1.0, during segmentation, can the methods such as marking be taked to distinguish each section on section bar 20.
Step 2: heating.Section bar 20 is heated to 650 DEG C ± 20 DEG C, and temperature retention time is 4min/10mm ~ 5min/10mm, and insulation is less than 2h at total time.
Step 3: installation.As shown in Figure 4, section bar 20 is put into bending machine 1, after installation, section bar 20 lies in above two lower rolls 3, align with the center of top roll 2 in its center, described top roll 2 and two lower rolls 3 are positioned at the op section of section bar 20, manipulation crank 4 promotes two lower rolls 3 and moves up, until section bar 20 contacts with top roll 2, by top roll 2 and two lower rolls 3, section bar 20 is positioned on bending machine 1.
Step 4: the op section of bent section 20.As shown in Figure 5, manipulation top roll 2 rotates in the counterclockwise direction, two lower rolls 3 are rotated in a clockwise direction, section bar 20 is driven to move to its right-hand member direction, the linear velocity of described upper and lower roll 2 and 3 is 2400mm/min, meanwhile, the power loading 292KN to two lower rolls 3 makes it move up with the speed of 6.0mm/min and pushes up die mould material 20; When o point cantact with section bar 20 of lower-left roller 3, change the direction of rotation of top roll 2 and two lower rolls 3, drive section bar 20 to move to its left end direction, and ensure that the speed that constant and two lower rolls 3 of the linear velocity of top roll 2 and two lower rolls 3 move up is constant; When p point cantact with section bar 20 of bottom right roller 3, change the direction of rotation of top roll 2 and two lower rolls 3 again, section bar 20 is driven to move to its right-hand member direction, and ensure that the speed that constant and two lower rolls 3 of the linear velocity of top roll 2 and two lower rolls 3 move up is constant, until top roll 2 contacts with the mid point of the op section of section bar 20.In BENDING PROCESS, two lower rolls 3 move up all the time always and push up die mould material 20.Repeat aforesaid operations 5 times, now, op arc section reaches predetermined radius of curvature.
Step 5: shut down and detect the temperature of section bar 20, if continue bending operation when being more than or equal to 450 DEG C, if be less than 450 DEG C, then by step 2 melt down be heated to 650 DEG C ± 20 DEG C after continue bending no section again, temperature retention time reduces by half.
Step 6: the no section of bent section 20.As shown in Figure 6, the no section of section bar 20 is placed on two lower rolls 3 of bending machine 1, the mid point of no section and the center alignment of top roll 2; Manipulation crank 4 promotes section bar 20 and moves up, until section bar 20 contacts with top roll 2, by top roll 2 and two lower rolls 3, section bar 20 is positioned on bending machine 1.Manipulation top roll 2 is rotated in a clockwise direction, two lower rolls 3 rotate in the counterclockwise direction, section bar 20 is driven to move to its left end direction, the linear velocity of described top roll 2 and two lower rolls 3 is 1200mm/min, meanwhile, the power loading 426KN to two lower rolls 3 makes it move up with the speed of 7.6mm/min and pushes up die mould material; When o point cantact with section bar 20 of bottom right roller 3, change the direction of rotation of top roll 2 and two lower rolls 3, drive section bar 20 to move to its right-hand member direction, and ensure that the speed that constant and two lower rolls 3 of the linear velocity of top roll 2 and two lower rolls 3 move up is constant; When n point cantact with section bar 20 of lower-left roller 3, change the direction of rotation of top roll 2 and two lower rolls 3 again, section bar 20 is driven to move to its left end direction, and ensure that the speed that constant and two lower rolls 3 of the linear velocity of top roll 2 and two lower rolls 3 move up is constant, until top roll 2 contacts with the mid point of the no section of section bar 20.In BENDING PROCESS, two lower rolls 3 move up all the time always and push up die mould material 20.Repeat aforesaid operations 5 times, now, no arc section reaches predetermined radius of curvature.
Step 7: the pq section of bent section 20.Its operating process is with step 6, until the pq arc section after bending reaches predetermined radius of curvature.Fig. 7 is the view at the end of section bar 20 bends, now, and the mn section of section bar 20 and the alignment of qw section.The radius of curvature of described pq arc section radius of curvature=no arc section.
Fig. 8 shows the schematic diagram of the ring base 20 of the GH4169 alloy flash welding thin-walled ring adopting the method for the invention bending forming, this ring base 20 is in " D " font, be made up of two straight flanges 21, arc sections 23 and the excessive arc section 22 that connects described straight flange 21 and arc sections 23, the position that end is relative between two straight flanges has opening 24.