A kind of deep-cavity thin-wall flange part duplex forging forming method[technical field]
The invention belongs to automotive transmission parts forging molding field, be specifically related to a kind of deep-cavity thin-wall flange part duplex forging forming method.
[background technology]
Have part to be deep-cavity thin-wall flange forge piece in gearbox parts, common forging molding process one is open type forging molding, but band longitudinal direction+horizontal overlap, increase resistance, ensure being full of property; Two is that closed-die forging is shaping, does not have overlap, and forming punching head draw ratio close to 2, or reduces height of punch, but need increase drilling operating.The current Problems existing of above-mentioned technique is: the longitudinal direction+horizontal overlap in open type forging is greatly thick, high material consumption; In closed-die forging, drift is extremely low for oversize die life, or shortens the drift prolongation drift life-span but need to increase drilling operating.
[summary of the invention]
The object of the invention is to overcome above-mentioned deficiency, a kind of deep-cavity thin-wall flange part duplex forging forming method is provided, not only can eliminate the thick large overlap that open type forging produces, and the drift that there will be in existing closed-die forging can be avoided extremely low for oversize die life, or shorten drift extend die life but need the problems such as boring, effectively reduce material consumption, reduce operation.
In order to achieve the above object, the present invention includes following steps:
Step one: by the blank jumping-up after heating;
Step 2: adopt closed-die forging mould the blank forging after jumping-up to be gone out the bottom shape of forging;
Step 3: adopt forward extrusion mould by extruded for the blank forging bottom shape;
Step 4: the blank after shaping adopts hot punching except endoporus gross weight, obtains final forging.
In described step 2, the counterdie of closed-die forging mould is identical with forging bottom shape, and patrix is T-shaped mould, and during pressing mold, patrix and counterdie are completely closed.
In described step 3, the patrix lower surface of forward extrusion mould is identical with forging upper surface shape, forward extrusion counterdie is the cavity identical with forging part of the lower die shape, patrix coordinates with counterdie and flange position excess metal is extruded forging lower end downwards keeps blank lower end shape, the final forging molding of forging when mould reaches design shut height.
Compared with prior art, blank after jumping-up adopts closed-die forging mould to forge the bottom shape of forging by the present invention, adopt the mould of forward extrusion by extruded for the blank forging bottom shape again, finally adopt hot punching except endoporus gross weight, obtain final forging, realize deep-cavity thin-wall flange forge piece non-trimming, forward extrusion is shaping, not only can eliminate the thick large overlap in the forging of traditional open type; And avoid the drift that there will be in existing closed-die forging extremely low for oversize die life, or shorten drift and extend die life but need the problems such as boring.The present invention can reduce allowance and manufacturing procedure, reduces the material consumption of single-piece forging, effectively reduces production cost.
[accompanying drawing explanation]
Fig. 1 is the schematic diagram of step one of the present invention;
Fig. 2 is the schematic diagram of step 2 of the present invention;
Fig. 3 is the schematic diagram of step 3 of the present invention.
[detailed description of the invention]
Below in conjunction with accompanying drawing, the present invention will be further described.
See Fig. 1, Fig. 2 and Fig. 3, the present invention includes following steps:
Step one: blank 1 is heated to 1200 DEG C ± 30 DEG C jumping-ups;
Step 2: adopt closed-die forging mould 2 blank forging after jumping-up to be gone out the bottom shape of forging, the counterdie of closed-die forging mould 2 is identical with forging bottom shape, and patrix is T-shaped mould, and during pressing mold, patrix and counterdie are completely closed;
Step 3: adopt forward extrusion mould 3 by extruded for the blank forging bottom shape, the patrix lower surface of forward extrusion mould 3 is identical with forging upper surface shape, forward extrusion counterdie is the cavity identical with forging part of the lower die shape, patrix coordinates with counterdie and flange position excess metal is extruded forging lower end downwards keeps blank 2 lower end shape, the final forging molding of forging when mould reaches design shut height;
Step 4: the blank after shaping adopts hot punching except endoporus gross weight, obtains final forging.
The present invention adopts a kind of new closed-die forging+forward extrusion composite molding+punching to remove the method for endoporus gross weight, not only can eliminate the thick large overlap that open type forging produces, and the drift that there will be in existing closed-die forging can be avoided extremely low for oversize die life, or shorten drift extend die life but need the problems such as boring, effectively reduce material consumption, reduce operation.