SU1349819A1 - Method of producing thin-walled cylindrical shells - Google Patents

Abstract

The invention relates to mechanical engineering, in particular to the production of thin-walled shell structures, and can be used in the manufacture of shells in the structures of the oil and gas and chemical industries, metallurgy and construction. The aim of the invention is to reduce the capacity of the membranes under the action of axial compression. Sheet billet is bent along a conical pipe-base with a taper of 1 27 -3, welded it. Then, oval grooves with a major axis not less than 0.16 of the shell length are formed on the surface of the shell obtained. The grooves are located in the middle part of the shell evenly around the circumference and oriented with their major axis along the generatrix of the shell surface. At the same time, technological deviations are formed within the taper tolerance field and double Q or a series of grooves that change the mechanism of the shell resistance to the action of axial seeps. 3 il. $ (L with with 00 with

Description

 13

The invention relates to mechanical engineering, in particular to the production of thin-walled shell structures and can be used in the manufacture of: shells in the structures of the oil and gas and chemical industries, metallurgy and construction.

The purpose of the invention is to improve the quality of products by increasing the carrying capacity of the shells under the action of axial compression.

Figure 1 shows the shell; figure 2 - section A-L in figure 1; on fig.Z - section BB on fnig.1.

The method is carried out as follows.

For a structural element — a thin-walled cylindrical shell, which does not require precise dimensions in the end sections according to the conditions of work — they use a conical pipe pipe with a taper made as a technological deviation from the cylindrical form within the tolerance, but no less. The conical base pipe bends the workpiece from a hardened metal strip and weld its edges, obtaining a closed shell. Then, in the middle part of the shell, several oval grooves with a larger axis B, not

it is 0.16 the length of the shell L, orienting their major axis along the surface of the surface of Zolochka.

The depth of the recesses W is (3.5-5.0) s, where c is the thickness of the shell material, and the width of the recesses along the guide tj is 0.04-50.07 of the guide surface of the shell ().

When setting the base taper of about 3 ° and carrying out the above operations, the resulting shell 11 has a bearing capacity 42.8% higher than the corresponding cylindrical one.

Using base pipe with a co-; By an openness significantly exceeding 3 ° ice, a cylindrical shell can be created with permissible technological deviations. Giving it a taper of less than P27 and the formation of depressions does not lead to an increase in the insubstantial capacity of cylindrical shells. For small values of the major axis of the recess along the generatrix on 9 2

There is a tendency to reduce the carrying capacity of the shell.

Thus, an increase in the bearing capacity of thin-walled shells by forming a taper (or using an existing coupling) and artificially created depressions that extend along the generator leads ultimately to a high level of the bearing capacity parameter.

Example. Method implemented

-Rj, s / -

on shells with parameters

300,

  2.8. Shell Material - Steel

Kc-

Х18И9-Н with modulus of elasticity E 1,81 10 kgf / mm. The formation of recesses was made by drawing with a measured force to a depth of 3.5–5.0 of the shell thickness and a width along the length of the circumference of the shell in the middle part of the shell along the 0.04–0.07 guideline circumference. For the manufacture of shells, a rigid base pipe with a taper angle O 46 -3 ° 1b, made of steel and having longitudinal slots for supplying the electrodes of the welding machine, was used. The overall dimensions and shape of the base pipe correspond to the dimensions of the manufactured shells. The connection of the edges of the shells produced by spot welding. The operation of drawing out the grooves was carried out by mechanical shallow punching and drawing, either by punching it, or by a device for imitating local transverse technological disturbances.

Experimental results showed; that the optimum value of the taper, which ensures the high-carrying capacity of the cylindrical shell, not withdrawing it beyond the tolerances, lies in the range of 1 ° 27-3 ° with the minimum length of the recess 6. P, 16L.

The advantage of the proposed method is an increase in the bearing capacity of the shell due to the formation of technological deviations within the tolerance field to taper and a number of recesses that change the mechanism of the resistance of the shell to the action of axial forces.

Claims (1)

Invention Formula A method of manufacturing thin-walled cylindrical shells, in which the initial billet of anisotropically strengthened metal strip is bent with tension along the base pipe, orienting its strongest direction along the line of action of the working load, and welding, which is distinguished by the fact that, in order to increase the quality of products the bearing capacity of the shells at the action of the axis | axial compression, the billet is bent along a conic base pipe with a taper of 1 ° 2l -3 °, forming oval grooves with a major axis of not less than O, I6 shell length, having a depression in the middle part of the shell evenly around the circumference and their orientation point FIG. 2 Editor A. Kozoriz Compiled by V. Korobkova Tehred L. Oliynyk Proofreader O. Kravtsova Order 5213/6 Edition 731 Subscription VNIIPI USSR State Committee for inventions and discoveries 113035, Moscow,, Raushsk nab., 4/5 Production and printing company, Uzhgorod, st. Project, 4 FIG. 3