SU1301612A1 - Method of joining tubular elements with tube walls - Google Patents

Abstract

The invention is attributed to mechanical engineering, primarily to the manufacture of heat exchange equipment, namely the connection of tubular elements with tube sheets, and can be used in municipal, energy and chemical engineering. The aim of the invention is to simplify the equipment. For this, the auxiliary part, by means of which friction welding of the end of the pipe with the end face of the grate-tube orifice is carried out, is made in the form of a polyhedron and is installed with a gap in the recess of the mandrel having the same contour. The size of the gap is chosen so that, when the maximum torque is reached (at the end of the heating stage), the edges of the auxiliary part are cut off. No clamping elements are required for fastening the auxiliary part in the mandrel. 1 hp f-ly, 2 ill. with (L

Description

eleven

The invention relates to mechanical engineering, primarily to the manufacture of heat exchange apparatus, namely to the connection of tubular elements with tube grids of 1 mi, and can be used in municipal, power and chemical engineering.

The purpose of the invention is to simplify equipment and increase productivity,

Fig. 1 shows the friction welding operation of a tubular element and a tube sheet using a rotating auxiliary part; in fig. 2 - auxiliary detail.

The method is carried out as follows.

Assemble the tube rack 1 with tubular elements for welding so that the ends of the pipes 2 are installed at the level of the end edges of the flanged holes in the tube sheet 1.

The welding is performed by the auxiliary part 3 in the form of a polyhedron with a central hole with a diameter of d D, where D, is the inner diameter of the pipe 2, and the diameter of the circle inscribed in the polyhedron is equal to the outer diameter of the flanged hole. Due to the fact that auxiliary part 3 has the shape of a polyhedron, for example, a hexagon, it can be produced by low-waste stamping from the waste produced by cutting the tube sheet 1. Auxiliary part 3 of the insert of the mandrel 4, having the contour of part 3, and bringing The ends of the pipes 2 and the edges of the beaded holes in the tube sheet 1. The mandrel 4 with the auxiliary part 3 is rotated and formed with an effort P until the piece 3 with the tube grid 1 assembled with the pipes 2 is heated. aemyh parts 3 - J. Upon reaching the welding temperature Uwe lichivayut axial force to a value R., and welding is carried out.

The shape of the auxiliary part is selected in such a way that the rotation from the frame is transmitted without its clamping and the spontaneous (automatic) removal of the part from the engagement with the mandrel is ensured at the moment of the end of the heating stage. These two conditions are satisfied by a polyhedron, in particular, a hexahedron.

The cutting of the edges of the auxiliary part at the moment of the end of the heating stage occurs if the following inequality is maintained

M.

cr.

. M

Cr.4

where is m

kr. (

M,

; rl

M

cr.1

Where

R +

torque required to cut the edges of the auxiliary part, kg-mm; torque, acting on the auxiliary part, kg-mm:

 P, (R + b),

force required to cut the edges of the auxiliary part, kg; shoulder force, mm; clearance between mandrel and auxiliary part, mm

R, n And - t-

de p - the number of faces of the auxiliary

details;

A is the chord length of the cut face, mm;

t is the thickness of the auxiliary part, mm;

ultimate strength of the auxiliary part at the temperature of the end of heating, kg / mm.

b

 n. a t. G (R + u); 2

- ".".

P f-R,

the pressure of the mandrel on the auxiliary part at the end of the heating stage; friction coefficient; radius of the inscribed circumference of the auxiliary part. flax inequality, at which the boundary part is cut off at the moment of the end of heating, at the end looks like this

P

t 0 {R + u) - | -1

P-f-RI From this ratio you can determine the size of the gap t with which the part should be installed in the mandrel.

31301612

measures. A hexagon with a thickness of t 3 mm is taken as an accessory. Length s mm (determined by graph. Strength of auxiliary parts G 8 kg / mm with a radius inscribed in hexagon R 11 mm. Pressure

at

er to

This is what's being done in the region.

P mandrel to auxiliary part at the end of the heating stage is 18 kg / mm, friction coefficient f 0.18, Substituting these values into the formula

--- ii

2

 s

 p g

, R .

fR

- R,

I

we get u 1,5 MM,

The proposed method avoids the use of clamping elements for fastening an auxiliary part in a mandrel. The part is simply inserted into the recess of the mandrel having its contour. During the welding process, the auxiliary part rotates with the mandrel, and when the maximum torque reaches (at the end of the heating stage), the face of the part is cut. This allows you to simplify the control of the welding process, eliminating precise control over

Claims (2)

time, give up on braking devices. Invention Formula 1, Method of joining tubular elements with tube grids, in which a hole with flanging is made in the tube blank f5 0 five rods, insert the tube so that its end face is at the level of the end face of the screening orifice of the tube sheet, and they are sealed by friction welding by means of an auxiliary part installed in the drive mandrel, which is rotated during heating and rotation and forging, not withdrawal of the auxiliary part from the mandrel, characterized in that, in order to simplify the equipment, the auxiliary part is made in the form of a polyhedron, and its rotation is stopped by installing an auxiliary part in a mandrel having the same contour, with a gap ensuring its cutting at the moment of termination of heating, 2. The method of pop, 1, is different from the fact that the auxiliary detail nickname. performed in the form of a hexagon F. e. / ig.1 Editor I.Rogulich Compiled by I.Felitsin Tehred N.Glushchenko Order 1183/15 Circulation 976 VNIIPI USSR State Committee for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab ,, d.4 / 5 Production and printing company, Uzhgorod, Projecto st., 4 Proofreader L, Pat Ai Subscription