SU1735625A1 - Method of obtaining shear joint of the parts - Google Patents

Abstract

The invention relates to mechanical engineering. Summary of the Invention; make connected parts with rows of holes. In each part, the means of spreading the fasteners of the outermost row are made in the form of recesses in the zone of the penultimate row of holes relative to the place of application of the load on the part with the maximum depth of the hole on the line connecting the axes of the holes. Then install the parts in the package, install the fasteners in the holes of the package and tighten them. 4 yl

Description

The invention relates to mechanical engineering and can be used in the manufacture of multi-shear bolted and riveted joints of increased fatigue life.

The design of multi-shear bolted connections is known. The fatigue life of known compounds is largely determined by the level of stresses on the walls of the extreme rows of holes for fasteners.

Methods are known for the elastic assembly of compounds in which, due to the preliminary deformation of one of the parts being joined, they are unloaded according to stresses of the extreme numbers of holes.

However, the known methods are energy-intensive and technically difficult.

A multi-joint structure is known, in which the preliminary process voltage on the wall

the extreme rows of holes are created by the bolt fasteners themselves.

However, the known joint requires high precision mutual manufacturing of the hole and bolt for it and is applicable mainly for single-cut joints.

The closest in technical solution and the achieved result to the invention is a method of obtaining a multi-shear connection of parts, which involves installing a pre-curved gasket between the parts to be joined, which, when axially tightening the fasteners, spreads the end rows of fasteners to the side. load on the connection, producing a significant decrease in the stress level of the see under operating conditions.

However, the known method significantly complicates the assembly of the joint, since it requires the use of an additional part and

WITH

with

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go ate

its exact connection with the parameters of the sheets to be joined, and the installation process of fasteners makes the application of the known method only for rich joints.

The purpose of the invention is to simplify the process of obtaining a compound.

In order to achieve this goal, the method of obtaining multi-shear connection of parts includes the manufacture of connected parts with rows of holes, making at most parts of the fastening elements of the extreme rows in the form of recesses in the piece to be joined in the area of the last but one row of holes relative to the location of operating load and the maximum depth of the recess on the line connecting the axes of the extreme holes, the installation of parts with the means of expansion into the package, the installation of fasteners in the holes keta parts and their axial tightening.

Figure 1 shows the parts to be joined in an assembly bag in longitudinal section of the joint; figure 2 is a view of And figure 1; FIG. 3 shows the bolted joint design of the parts, the profile projection; 4 is the same, the nature of its operational load.

The method of obtaining the multi-joint connection of parts 1-3 consists in making several rows of holes 4 under fasteners 5 in them. On the parts to be joined, the means of spreading the extreme rows of fasteners in the form of recesses 6 and 7 are made. The grooves have the greatest depth in the zone of the penultimate row relative to the place of application of the operational load Re of the holes and on the line connecting the axes of the extreme holes. The connected parts are installed in a package (they align the axes of the holes), and then fastening elements 5 (e.g., bolts) are installed in the joint holes, and their axial tightening is performed. The axial tightening of fasteners is advisable to be done first for the inner and outer rows, and then for the penultimate (at the location of the expansion tool) rows. After axial tightening of fasteners, technological stresses arise on the walls of the extreme rows of holes.

Neither see Ty 7yu, the direction of which in the parts being destroyed over this section is opposite to the operational one. The developed method of obtaining the joint is simpler when assembling the joint and has a large scope for riveted joints. It is advisable to drill in the parts at the stage of manufacturing the part (for example, by milling), while

Longitudinal, relative to the load on the joint, the size of the recess is chosen as the largest of the ratio:

15

BP -2tp-2d,

0)

where BP is the width of the recess; tp is the regular step of fasteners; d - diameter of the fastener.

Depth depth choose such

so that the magnitude of the previously created cm. stresses would be equal to the operational ones. In this case, the magnitude of the resulting cm aoi stress is equal to or close to zero, and the fatigue life of the joint is equal to the fatigue life of the strip with an unloaded filled hole.

The developed method of obtaining a multi-compound allows to simplify

the process of assembling a compound that brings an economic effect in terms of its manufacture.

Claims (1)

The invention method of obtaining multi-shear connection of parts, including the manufacture of connected parts with rows of holes, the implementation of means of spreading fasteners of extreme rows, the installation of parts with tools of spreading in the runway with the location of the latter in the zone of the last but one rows of holes the holes of the package of parts and their tightening, characterized in that, in order to simplify the process of obtaining a joint, the means of spreading the fastening elements of each extreme row are made into e recesses in the joined part in the zone of its last but one row of holes relative to the place of application operating load with a maximum depth of recess on the line connecting the axes of the said holes. 4 / iT.I Buc) J I