SU778958A1 - Method of determining elastic-shrinkage value of complex cross-section hole at choosing outer diameter of broaching tool deforming element - Google Patents

Description

(54) METHOD FOR DETERMINING THE VALUE OF ELASTIC SHEET

HOLE OF THE COMPLEX PROFILE WHEN SELECTING THE EXTERNAL DIAMETER OF THE DEFORMING ELEMENT

one

This invention relates to metalworking and can be used in the selection of design parameters for deforming wires.

A known method for determining the elastic shrinkage of the holes of a complex profile when selecting the outer diameter of the stretching element of the broach, includes trial stretching of the hole with the deforming element, the outer diameter of which is equal to the nominal diameter of the hole 1.

With this design, the reliability of the results obtained and the complexity of the execution are high.

The purpose of the invention is to improve the accuracy and simplify the method.

The goal is achieved by the fact that the hole obtained after the test drawing is pulled by a cutting circular broach, the teeth of which have a continuous blade, determines the diameter of the tooth on which the first annular tooth is formed.

TRIPS

undivided chips and take on shrinkage ratio

2 b DIC - D 1

5 where 8 is the value of elastic shrinkage over the hole diameter, mm;

DK is the outer diameter of the deforming element, with the help of which test drawing is carried out, mm;

 - the outer diameter of the first to the front shank of the tooth on which annular chip chips are formed, mm.

FIG. 1 is a sectional view of the treatment hole s; in FIG. 2 - drawing scheme.

To determine the shrinkage b on the outer diameter DH of the part 1, its workpiece with a pre-machined hole 2 20 is drawn by drawing 3 with a deforming element 4, in which the profile corresponds to the profile of the part 1 (the direction of the pull is shown in the arrow M).

The outer d-diameter D of the deforming element 4 is selected; 1 | min) the overall outer diameter DH of the workpiece hole 1.

After trial drawing by pulling 3, elastic shrinkage of the opening 6 occurs and the diameter of the workpiece becomes equal to Ots-25. Then, the workpiece in the N direction is pulled by a draw (piercing) having cutting teeth 5 with continuous blades (without chip-making elements). During the cutting process, a portion of the teeth 5 cuts apart the split chips, which is removed (falls) from the spacing, and the other part of the teeth cuts off the annular chips, which remain as a ring on the body of the spacing 3.

After pulling the cutter 3, the tooth 6 is determined, on which the first annular chip is formed and its diameter D is set.

The amount of shrinkage is determined from the ratio.

26 DK- D „

feed per tooth Sz is selected on the basis of the given (required) accuracy of shrinkage determination, the smaller the feed, the better the shredding,.

where 6 is the value of elastic shrinkage over the outer diameter of the hole, mm; D (c is the outer diameter, deforming the brush of the element, with the help of which test drawing is carried out, mm;

D is the diameter of the first to the front shank of the tooth on which ring chips are formed, mm. Thus, the proposed method provides for the given accuracy of the machined holes and allows to simplify the definition of the shrinkage of the hole of a complex profile during deformation.

Claims (1)

Formula of inventions The method of determining the elastic shrinkage of the orifice of a complex profile when selecting the outer diameter of the deforming element of the broach, including trial drawing of the hole with the deforming element, the outer diameter of which is equal to the nominal diameter of the hole, characterized in that, in order to increase the accuracy and simplify the method, the hole obtained after the test drawing is drawn by a cutting circular drawing, the teeth of which have a continuous blade, the diameter of the tooth on which the first is formed is determined rotating arm undivided chips and take-size shrinkage ratio 2D DK-DV where 6 is the value of elastic shrinkage according to the hole diameter, mm; B c is the outer diameter of the deforming element with which the test drawing is carried out, mm; D (is the outer diameter of the first to the front shank of the sleeve on which an annular undivided chip is formed, mm. Sources of information taken into account during the examination 1. Development of designs of carbide with deforming elements. Report VNII. Topic 9-75, M ., 1976, pp. 27-29.