Progressive die set for punching, trimming and straightening forgings of box nut wrench
FIELD: plastic working of metals, possibly operations for finish working of forgings of double-end box nut wrenches.
SUBSTANCE: die set includes upper and lower plates with guiding columns, punch for punching operation mounted on upper plate, stripper, lower die for punching, half-open trimming lower die and trimming punch. Trimming lower die is mounted on upper plate; it has cutting edge and cavity arranged behind collar of cutting edge and designed for freely placing forging of nut wrench. Trimming punch is mounted on lower plate and it has embracing supporting surface for fixing forging at trimming and straightening operations.
EFFECT: enhanced quality of forging.
9 dwg, 1 ex
The invention relates to the processing of metals by pressure, in particular to the stamps, designed to perform finishing operations - punching holes in the forging, cutting burrs and correcting deformities, and can be used for forging bilateral direct mechanical wrenches.
Known serial stamp for trimming burrs and firmware holes in the forging, comprising upper and lower plates with the guide columns, piercing and edged punches mounted on the top plate, piercing and edged matrix with holes for failure and puller piercing punch (Bryukhanov A.N., reference "Forging and die forging steel" Ed. by M.V. Storozheva, volume 2, page 282, Fig. 23, ed. "Engineering", M., 1968).
When applying the known stamp for the production of finishing operations on the forging of bilateral direct mechanical wrenches obtained on horizontal forging machines (GCF), i.e. for punching holes in the lugs of the heads of the key under the crank, as well as for trimming burrs, the following shortcomings were revealed.
First, when punching holes in the eyelet head of the key is the curvature of the forging in the form of a small limb of the head relative to the rod. The amount of curvature is affected by the condition of the cutting edges of the piercing punch and the gap between the full color is developed and the punch. The increase of the gap causes an increase in the degree of curvature of forgings, which may exceed the permissible deviation from the alignment.
Secondly, used in the famous stamp method of fixation of the forgings to cut the matrix on the outer contour for forgings mechanical wrenches do not always provide the correct location forgings relative to the cutting edges and high-quality crop. So when exceeding the size of the forging of the appropriate size of the matrix, i.e. in cases permitted "mitre" body forging trimming burrs, the bottom surface of burrs when fixing forgings not in contact with the surface of the matrix and can be positioned at an angle to the latter. For forgings mechanical wrenches this is expressed in a possible reversal forgings relative to the longitudinal axis during its installation and fixing, which causes of marriage in the form of partial cutting and crushing burrs. Thirdly, transferred from the position of the punch without rotation about the longitudinal axis and mounted on the position of the trimming curved forged key is bent up head and the rod. Therefore, in the process of trimming the head and rod forgings rest against the abutment surface covering the cavity of the trim punch is not over the entire surface, but only along the lines of the original touch, which leads to local wrinkling with Erina and head. Crushing the edge of the head end of the key causes distortion of the geometric shape of the inner hexagonal cavity.
Technical problem on which the invention is directed, is to improve the quality of forging bilateral direct mechanical wrenches due to elimination of disadvantages inherent in the known serial stamp by changing its layout and design.
The problem is solved in that in a sequential stamp for punching, cropping and editing forgings mechanical wrenches, comprising upper and lower plates with the guide columns, piercing punch, fixed on the top plate, a stripper, a matrix for punching with a hole to failure, the semi-edged matrix with cutting edge and trim the punch with the covering surface, edged semi-open matrix attached to the top plate and located behind the belt of her cutting edge cavity for free placement head wrench, trim punch is fixed on the bottom plate, and its covering the surface of the support under condition of providing commit forgings during trimming and editing.
Common features of the claimed invention and the known serial stamp for trimming burrs and firmware holes in the forgings are available in the stamp top and bottom plates with guide columns, punch punch mounted on the top plate, puller, matrix punched with a hole to failure, the semi-edged matrix with cutting edge and the trim punch with the covering surface.
New features in the invention are:
- cut half-open matrix attached to the top plate and located behind the belt of her cutting edge cavity for free placement head forgings wrench;
- low-cut punch is fixed on the bottom plate, and its covering the surface of the support under condition of providing the fixing forgings during trimming and editing.
Forging the stamp by the present invention after punching the holes is removed from the punching position and is moved to the position of the cutting burrs with a folded up head. The combination of the new features of the claimed invention provides the following results. First, in contrast to the known stamp forging trimming burrs is fixed to the outer cavity of the trim punch fixed on the bottom plate. The recording head forging is carried out both by the external contour and focus on the plane of the lugs. Additional fixing a focus in the plane of the lugs prevents the spread forgings relative to the longitudinal axis and provides compared the structure with a known stamp more accurate fitting forgings on the position of the trim. Secondly, securing the trim of the matrix on the top plate eliminates the possibility of local buckling bent head and rod forgings, as a semi-open square matrix has a cavity to accommodate them at a scrap and is in contact with the forging of only clipping path. Thirdly, in comparison with the known stamp when cutting burrs need to edit lamina head forgings Allen key, that is, the correction of the curvature of forgings obtained from the punched hole. Edit bent head to the magnitude of deviation from the alignment head and the rod is in covering the cavity of the trim punch, which simultaneously plays the role of a referential stream by the force of the impact on the forging edged matrix through a curved burrs, mounted on the cylinder along the axis of the forging on the sides of the space curvature. The direction of the straightening of the limb coincides with the direction of the cut matrix. The effort to edit is created due to the forces occurring when cutting Burr.
Eliminating specified by the disadvantages of the known serial stamp used to perform finishing operations on the forging of bilateral direct mechanical wrenches, allows to improve the quality of forgings.
Figure 1 shows the serial stamp for probe the key, cropping and editing forgings mechanical wrenches, General view in section; figure 2 is a top view (without top plate); figure 3 - cross-section B-B in figure 1; figure 4 - section b-b In figure 3; figure 5 - the forging of bilateral direct socket wrench after stamping on GCF; figure 6 - view of G on figure 5; figure 7 is a section d-D figure 5; Fig - place E figure 6; figure 9 is a simplified diagram of the trimming burrs forgings and editing.
Serial stamp for punching, cutting and editing of forging bilateral direct mechanical wrenches 1 having a head 2 burrs 3, contains the upper 4 and lower plate 5 connected to the guide columns 6. The plunger 7 is attached to the top plate 4, and the matrix 8 is designed for punching holes d under the crank lug head 2 Allen key. To remove forgings with piercing punch 7 is a stripper 9. Matrix 8 has failed opening to remove waste after punching located over a failed window in the bottom plate 5. Semi-open matrix 10C cutting edges for trimming burrs attached to the top plate 4. For belt cutting edges, the matrix has a cavity 11 for free placement head 2 key after trimming burrs. Cut the plug 12, is fixed on the bottom plate 5, at the same time serves for fixation forgings before trimming, which is pose the STV covering the cavity end support surface of the punch. Figure covering the cavity is performed by forging with regard to maximum permissible values of the limiting variance. The offset of the forgings in the horizontal plane is limited to the outer covering and the contour of the cavity of the punch, a possible reversal forgings relative to the longitudinal axis is limited by contact with the plane 13 of the lugs between the punch and forging. Burrs 3 forgings 1 before trimming are all above the covering of the edges 14 of the punch and do not affect the accuracy of the record.
Stamp works as follows. Forged socket wrench 1 is placed in the locking cavity of the breakdown of the matrix 8 and after pressing the stripper 9 is punched hole d-piercing punch 7. After punching forging receives a small limb head 2 upward relative to the rod, and the line of the curve passes through the centerline of the punching action of the punch, that is on the axial line of the hole d. Further, the position of the punching forged rotation about the longitudinal axis to carry and fits in the locking cavity of the trim punch 12. When the motion of the upper plate 4 down at the beginning of the cropping square matrix 10 is in contact with the curved Burr in those places, which are located on the sides from the centerline of the hole d. In the process of trimming the influence of the matrix on the burrs is transferred to the forging and wyprawa is it. Proposed in the claimed invention schema edits similar pattern V-shaped flexible (Moshnin E.N., reference "Forging and die forging steel" Ed. by M.V. Storozheva, volume 2, page 167, Fig. 2, ed. "Engineering", M., 1968), and the force is transmitted through the flexible cropping Burr. Condition for straightening the curvature of the forging in the form of the limb head should be performing ratio:
Robr.≥ Lib., (1)
where Robr. - force cutting burrs;
Lib. required bending force on the cross section passing through the centerline of the hole d.
When bending the magnitude of the normal stresses in the cross section of the bending parts depends on the bending moment and shearing from the magnitude of shear forces. With decreasing distance between supports L bending moment is reduced and the curve with length L<4 h, where h is the thickness of the part, in the calculations of the efforts of flexible should be based on the magnitude of shear forces: Q≈ 0,5· F.· GB(Moshnin E.N., reference "Forging and die forging steel" Ed. by M.V. Storozheva, volume 2, page 169, f-La (5), ed. "Engineering", M., 1968),
where F. - the cross-sectional area forgings centerline hole d;
GB- temporary tear resistance of flexible material details.
The distance L at the beginning of the crop is defined as the length of the projection of burrs on the longitudinal axis of the forging, the process is editing the value of L will be even more reduced. For item number keys of type I with internal hex, forged, two-way, direct correlation of L<4 h is (Keys mechanical special Technical conditions TU2-035-550-95, JSC "Pavlovsky instrumental plant", 1996).
The required bending force to the cross section along the centerline of the hole d:
Lib.=Q· L/B≈ 0,5· F· GB·L/B (2)
where is the distance from the edge of the head of the key to the centerline of the hole d.
Force trim Burr is determined by the ratio (Bryukhanov A.N., reference "Forging and die forging steel" Ed. by M.V. Storozheva, volume 2, page 255, ed. "Engineering", M., 1968):
ROP.=(1,5-1,8)· GB·Fcp, (3)
where GB- ultimate strength;
Fcp=t· lcp - square cut;
t - thickness of the cropping burrs;
lcp is the perimeter of the slice.
Substituting in equation (1) expressions (2) and (3), the condition for straightening the curvature of forgings mechanical keys specified in the following form:
(1,5-1,8)· GB·Fcp≥ 0,5· F· GB·L/C.
Taking the left side of the minimum values and thereby reducing inequality, the condition edits forgings can be represented in the form:
1,5· Fcp min≥ 0,5· F·/; or F≤ 3· Fcp min·/L, (4)
where Fcp min - minimum square cut, Burr is the maximum size of the matrix, the minimum size of forgings and considering cutting curves at the transition from the body of the forging to the burrs.
The equality of the left and right parts of the equations (4) sets the largest value F at which the effect begins straightening the curvature of forgings mechanical keys. In case of equal or exceeding the right part of the ratio of the cylinder forgings after correcting comes in contact with covering the support surface of the punch 12. As undercut matrix 10 has a cavity 11 for the free accommodation of the head of the key, after pruning eliminates local crushing of the head and rod forgings 1 and the deformation of the inner hexagonal cavity.
Example. Produced and mastered in the production serial stamp for punching holes, cutting burrs and straightening of the limb head forgings direct two-way socket wrench steel 40X hot with head size: S=27 mm; D=39,1-40,5 mm; L=65 mm; B=46 mm, h=21 mm; d=20 mm; F=385,4 mm
Cut burrs 3 are formed on the parting line of matrixes for production of forgings on the GCF. The thickness of the cut burrs t=1 mm, the perimeter of the slice t=135 mm, the radius at the transition from the body forgings for burrs r=1.5 mm width of cutting path edged matrix U=39,69-40,31 mm
The maximum value of residual protrusion from burrs when cutting:
DL is e=0.6 mm slice thickness with consideration of radius r=1.5 mm is determined graphically or by calculation: t min=1,6 mm Minimum cutting area: Fcp min=t· Lav=1,6· 135=216 mm2. The condition edit (4):
F≤ 3· Fcp min·/L; 385,4<3· 216· 46/65=458,6 - executed.
The stamp has been part of the stamping line. After landing head key GCF hot forging is fed by a conveyor to a stamp. First is punching holes d, then trimming burrs 3 on the contour of the head. Operations on the stamp are in a hot state from a single heat. After punching the holes formed a small limb of the head relative to the rod. When cutting burrs matrix lies on the burrs and straightens a limb head and, with further cuts during the burrs. Contact semi cut-die forging is carried out only through the side burrs, so cases of collapse and deformation of the rod and the head of the key when working is not observed. The sequential design of the stamp, made in accordance with the claimed invention, in the production of proved efficiency. Quality forgings meets the requirements.
Thus, the use of the claimed invention eliminates the disadvantages of the known serial stamp, used for trimming burrs and flash hole forgings, and should be proposed by the claimed image the structure of the serial stamp punching holes, cutting burrs and editing forging bilateral direct mechanical wrenches compliance with quality requirements. This result is achieved by changing the design and layout of the known stamp.
Serial stamp for punching, cropping and editing forgings mechanical wrenches, comprising upper and lower plates with the guide columns, piercing punch, fixed on the top plate, a stripper, a matrix for punching with a hole to failure, the semi-edged matrix with cutting edge and trim the punch with the covering surface, characterized in that the undercut semi matrix attached to the top plate and located behind the belt of her cutting edge cavity for free placement head forgings wrench, trim punch is fixed on the bottom plate, and its covering the surface of the support under condition of providing the fixing forgings during trimming and editing.
FIELD: forging and forming processes and equipment, namely manufacture of elongated forgings with thickened portions and lateral branches.
SUBSTANCE: die set includes deforming punch, die with vertical parting, struts in the form of truncated pyramids having wedge-shaped slopes for mounting die; units for securing struts to supporting plate. Die is placed in struts with possibility of motion relative to them. Struts have double-sided mutually opposite slopes. Elastic member is placed under die. Maximum compression value of said elastic member by means of effort corresponding to effort of clamping die halves in struts is equal to value of descending die at forging process.
EFFECT: enhanced reliability and rigidity of die set.
2 cl, 1 dwg, 1 ex
FIELD: metal working.
SUBSTANCE: hard alloy matrix has casing, bushing pressed in the case and hard alloy insertion. Bushing has multifaced hole. Hard alloy insertion is composed by several sections made in form of trapezoidal-section prisms which have cut angles at their non-working edges. Number of sections corresponds to number of faces of item to be headed. Cuts of angles are made symmetrically to faces of working edge. Slits are made in several places of multifaced hole bushing at the ponts where faces cross each other.
EFFECT: improved resistance of matrix; simplified assembly.
3 cl, 1 dwg