SU1690935A1 - Method for making stem-like parts with enlarged portions - Google Patents

Abstract

The invention relates to the processing of metals by pressure and can be used in the manufacture of core parts with thickening, the workpieces of which have a free stampable area exceeding its diameter by more than 2-2.5 times. The goal is to expand technological capabilities, improve the quality of the parts produced, increase tool life. U2 is the strain rate; hi is the length of the deformable part of the workpiece in the initial period of precipitation; ha is the length of the deformable part of the workpiece, which is necessary for a set of metal to thicken the part; S is the amount of movement of the punch. The value of the current ratio of the free length of the deformable part of the workpiece to the diameter is established not exceeding the condition of longitudinal stability. 4 il.

Description

The invention relates to the processing of metals by pressure and can be used in the manufacture of core parts with thickening, the workpieces of which have a stamped area greater than its diameter more than 2-2.5 times.

The purpose of the invention is to expand technological capabilities, improve the quality of the parts and increase tool life,

FIG. 1 shows a flow chart of the method; in fig. 2 - initial blank; in fig. 3 — forging after transverse extrusion; in fig. 4 - forging after disembarkation.

The method is carried out as follows.

Heated to 800-850 ° C, the billet (Fig. 1) with mass and quality that meets the requirements of precise stamping and a diameter equal to the diameter of the stamped rod enters the stamping position where the extrusion of the rod is transversely extruded (Fig. 3). In this case, the matrix receives movement at a higher speed than the punch, and the speed of the matrix is determined from the condition that the longitudinal stability of the deformable part of the rod is preserved by the formula determined from the following relationships.

Matrix speed

their

where X is the path length of the matrix,

ON H O O

w

SP

t is the time of movement of the die, the speed of movement of the punch

m S,

where S is the amount of movement of the punch;

t - time of movement of the punch.

The length of the deformable part of the workpiece

h2 hi + X S + H0,

where hi is the length of the deformable part of the workpiece in the initial period of transverse extrusion;

H0 is the length of the bulge (set of metal). C but do do

where K 2 is the accepted known condition of current longitudinal stability, at which But hi is in the process of lateral extrusion, and hence, 1) 2 Ui.

From the equality hi + X S + Н0 we find X

X S + Ho-hi or

Then.,

X Ui (1 + - ° s h1)

From the condition of equality of time of movement of the punch and the matrix, we find

(1 +).

From the condition of equality of the volumes of the metal before deformation and after deformation, we find -j do ha -t Do H0, where d0 is the diameter of the core of the workpiece.

Then from the condition -r- -rg2- K get QO LJo

eat h h2 H2, H0, whence H03 hi2 ha or Ho {h2i h2) 1/3. Consequently,

ua +) s1 / 3-h2 After the set of metal, the transverse extrusion process ends (U2 0) and then the head disembarks (Fig. 4).

The movement of the movable matrix at a higher speed than the speed of the punch is determined by the formula, provided that longitudinal stability is maintained, which allows the metal to set into the head of a large diameter rod from a billet of LO 2 pressure on the tool.

Example. From the piece blank (steel 40x) with a diameter of L0 9.5 mm and length h 71.8 mm (Fig. 1) in the first stage of the process of stamping by transverse extrusion at 850 °

With a ratio of the free length of the part to be stamped (hi 19 mm) to a diameter (d0 9.5 mm) equal to 2.0 (this is a condition of longitudinal stability for this example), the metal is set to thicken

(for the required set with a diameter of D0 11.3 mm from a billet with a diameter of do 9.5 mm, a billet length of P2 36 mm is required, the ratio of length to diameter is 3.7, which exceeds the condition of longitudinal stability, the deformation rate is equal to 0.25 m / s). Therefore, a set of metal in the thickening is produced by moving the matrix at a speed determined by the formula

U2 0.34 m / s.

At the end of the transverse extrusion process, a thickening with a diameter D0 of 11.3 mm and a length of H0 of 23.5 mm is obtained.

n (-rp 2.0). A landing is then performed.

Claims (1)

heads with a diameter of 18 mm and a height of 10 mm. The invention The method of manufacturing core parts with thickening, including the placement of part of the workpiece in a movable axially spring-loaded matrix, having the ability to move in the direction coinciding with the direction of movement of the punch, landing thickening, characterized in that, in order to expand technological capabilities, improve the quality of the parts and increase tool life, the matrix is moved at a speed exceeding the speed of movement of the punch and satisfying the ratio Ua Ui 1+ (hbh2) 1/3 -hi one where Ui is the speed of the punch; U2 is the velocity of the matrix; Ui is the length of the landing part of the workpiece during the initial landing period; h2 is the length of the part of the billet that is planted; it is necessary for a set of metal to thicken the part; S is the distance to move the punch. J N o S4jl f Fi2.s