SU1682655A1 - Method of receiving multirow connecting of parts - Google Patents

Abstract

The invention relates to mechanical engineering and can be used in connecting various parts with each other. The purpose of the invention is to increase the service life by increasing the fatigue life of the joint. Parts with rows of holes and gasket with bends between the holes are made. Put them in a bag. Install the fasteners into the opening of the package and tighten them. The bending of the gasket has a value, (successively decreasing from the extreme sections between the rows of holes to the middle of the gasket. 4 Il.

Description

The invention relates to mechanical engineering, in particular to aircraft construction, and can be used in the manufacture of multi-shear bolted connections.

The aim of the invention is to increase the service life by increasing the fatigue life of the joint.

FIG. Figure 1 shows the construction of a single-threaded single-bolt joint of parts before tightening the bolts; in fig. 2 - structures and geometrical dimensions of the spacer; in fig. 3 - design and parameters of the stress state after axial tightening of the bolts; in fig. 4 shows the design and parameters of the stress state after axial tightening of the bolts and application of the operational load.

The joint of parts consists of joined sheets 1 and 2 and fasteners - bolts 3, washers 4 and nuts 5. A high-strength gasket 6 is installed between the joined sheets. It has a variable bend that varies along the length of the joint between the rows of bolts. The place of fatigue fracture of the joint is the section along the first relative to the operational load Rae of the bolt holes: the section along the line A-A for sheet 1 and the section along the line B-B for sheet 2.

Variable from the extreme p of the bolts to the internal bending of the gasket is realized by successive displacement of the holes in the sheets and gasket. Suppose that sheet 1 has a regular pitch of holes ti, t2, ta, t4 (Fig. 1), and a gasket, respectively, tp, tp, tp. tp. Making the axes of the holes (relative to the middle row) in the gasket in the direction of the load Atp and D tp1 acting on the sheet, while Atp2 A tp1 (Fig 2) results in alternating bending of the gasket when the joint is assembled.

After axial tightening of the bolts, the curved gasket rectifies and expands more

About 00

ho

about

SL

cl

you are from the inner yes to the extreme. On the walls of bolt holes occur

7 cm cm i, technological stresses, the action of which is opposite to the cm cm operating stresses,

moreover, i i oЈm 2 (FIG. 3), i.e. bolt thrust increases from inner row to extreme.

After the application of the operational load Re, a redistribution of the seepage voltage occurs along the rows of holes, moreover

OM I I + OSM I, No.

where OCM i is the magnitude of the see-through stresses on the -th hole under the action of the operating load Re without the use of expansion bolts.

Since the direction is 0TM | from the inner row of bolts to the first row is opposite to I, and from the inner to the last

The number of bolts coincides with i. Then, the magnitude of the resultant stress of smith gradually increases from the first row of bolts to the last (Fig. 4), i.e.

(That 1 SGSM 2 Om 3 Om 4 Om 5.

Thus, the implementation of the principle of rational joint design according to the criterion of fatigue life occurs.

The use of this compound is advisable for multilateral (with the number of

more than four) one and two shear connections. For an even number of rows, one of the inner ones is taken as the middle row, or two shear rows are combined (without bending the gasket between them).

Thus, the proposed method of joining parts allows for a uniform load of the joint.

along its length, which increases its fatigue life and leads to an increase in the life of the joint.

Ф орм ул а and з о б р ё te n and

A method for producing a multi-part connection of parts, in which parts are made with rows of holes and a gasket with corresponding rows of holes and with bends in the outer sections located between the extreme rows of holes and adjacent intermediate rows, connect the parts and the gasket between them in the package, install fasteners

elements in the package apertures and tighten them, characterized in that, in order to increase the service life by increasing the fatigue life of the joint, the gasket is made with similar bends in the areas between the intermediate rows of holes, and the deflection is successively reduced from the extreme sections to the middle of the gasket .

1

2

0V

JCMl

1

РЗ

FIG. four

Claims (1)

Claim A method of obtaining a multi-row connection of parts, in which parts with rows of holes and a gasket with corresponding rows of holes and with bends in the extreme sections located between the extreme rows of holes and adjacent intermediate rows are made, connect the parts and the gasket between them in a package, install fasteners in the holes of the package and tighten them, characterized in that, in order to increase the service life by increasing the fatigue life of the connection, the gasket is made with similar bending E at sites between the intermediate rows of holes, and successively reduce the amount of deflection of the edge regions of the middle pad. Ati - ..... P77G '' T77777777G ~ V77777777TTV77777777P k / y /1 'tp 1 tp Λ tp ** ----- C ---- i * FIG. 2 Fig. Figl