SU848125A1 - Cone production method - Google Patents

Description

t

This invention relates to methods for changing the diameter of pipe ends by pressure treatment.

A known method of making cones from reinforcing materials consists in forming a pre-cone from a tubular billet, and then forming a cone with a crimp of the required dimensions with the same material hardening along the length of the D-1 generatrix.

However, this method has limited application possibilities for the angle of inclination of the generatrix, i.e. the process capabilities are in a narrow range, approximately 20-25 and limited capabilities due to the presence of a distribution operation in it (the permissible degree of deformation during distribution is approximately 2 times less than during crimping). In addition, the presence of the distribution operation, in which the initial workpiece is thinned, and the crimping operation, in which the initial loading is thickened, determine the significant differences in the thickness of the parts produced, and the presence of various loading patterns significantly reduces the accuracy of the parts produced. elastic deformations (spring).

The purpose of the invention is to increase the range of values of the angle of inclination of the Forming cone, increasing the degree of deformation and accuracy of the part in thickness and geometric contours.

The goal is achieved by the fact that, in the method concluded in

10 forming a pre-cone from a tubular billet, and then molding a " -cone of required dimensions with the same material hardening along the forming length; determined from

20 expressions

di

--51 and de

about 1-g

1st

- larger diameters and

and dfl

where DO are the smaller bases of the preliminary cone;

 d,

-diameters of larger and smaller bases from.-delhi;

g is the degree of deformation at 30 kg.

FIG. 1 shows the initial tubular billet with a diameter DO and height ND; in fig. 2 - cone after pre-crimping on angle d and diameter dg; in fig. 3 - the same, after the final crimping of the conical billet (which has undergone the heat treatment operation after the first crimping) with the same degree of deformation along the entire length of the cone forming the ria angle ci-j and diameters 0; FIG. 4 - dimensions of the preliminary cone; in fig. 5 - dimensions of the finished product; in fig. 6 and 7 are schematic diagrams for obtaining a preliminary cone and crimping this cone for the obtained product.

The method is carried out as follows.

A cone shell is made from an AMgb alloy, the mechanical properties of the material of which, according to the conditions of operation, are at the level of the properties of the AMgbNN alloy according to OST 1-92001-71 ((22 kg / mm; Cie - 33.5 kg / mm; ()).

In connection with the absence of OST 1-92001-71 plates with a thickness of 20 mm with the required mechanical properties, a plate with a thickness of 20 mm from AMgbm alloy having GQ mechanical properties of .31 kg / mm is used as the initial billet; With 15 kg / mm; (5 11%.

I

Deformation of closed conical or cylindrical shells with a degree of deformation of at least 15% has been found to increase cGy from 31 to 42 kg / mm, (3 from 15 to 34 kg / mm and decrease (T to a value of at least 7%. To obtain the required the degree of hardening of the material of the finished shell, it is necessary to have a preliminary blank, the taper angle of which is greater than the taper angle of the finished part.

Dimensions of preliminary taper billet {see FIG. 4} is calculated from the condition of providing uniform hardening along the length of the generator and the thickness of the wall of the conical shell, according to the formula

di

o ° r-k

where 0 „, do are the diameters of the preliminary conical billet D and d are the diameters of the finished conical shell; g - the degree of deformation at

crimping. In this case

, 0 irifs- 2207 mm, 0 - 1924 mm.

 The taper angle of the preform is determined by the formula

fOl-rdi 1

arctg

2HU-eyj

H - the height of the finished cone

ZOTA GOTO shell. echayki. G1876 - 1640 1 .ni

9 L264-2 (i: 5: i5-rj

arc

Pre-taper height

the blanks are determined from the condition of equality of the lengths of the cones forming the finished part and the preliminary blank (see Figs. 4 and 5),

A preliminary conical billet is produced from a cylindrical billet by the method of longitudinal crimping according to the scheme shown in FIG. 6

Thus, the technological process of making a conical shell with increased mechanical

0 properties of the material includes cutting.plite, hemming of edges, rolling a cylindrical shell, welding a longitudinal weld, crimping a preliminary cylindrical shell into a conical, thermosetting (annealing), crimping strengthening (final production of a conical shell) according to the scheme presented in fig. 7

Manufactured according to the proposed

The shell method has a value of 6%.

45 kt / mm: СЭС- КГ / ММ: About 7%.

42 kg / mm

The ovality of the diameters of the shells does not exceed 0.1%, and the deviation from the straightness of the generatrix is 0.08 mm.

The proposed method makes it possible to manufacture parts with virtually any cone angle, which expands the range of manufactured parts, uses higher degrees of deformation as a result of the exclusion of the distribution operation, and improves the dimensional accuracy of the part in thickness and geometric circumferences due to smaller values of elastic shape during crimping.

Claims (1)

1. USSR author's certificate 633648, cl. B 21 D 41/00, 1976. F 1929 .-Lh