RU2475651C1 - Tightening method of high-load threaded joint - Google Patents

Abstract

FIELD: machine building.

SUBSTANCE: tightening method of a high-load threaded joint of parts, which consists of attached parts and a load-carrying bolt, consists in the fact that into the load-carrying screw attaching the parts, there screwed is an additional load-carrying bolt, into which an additional securing bolt is screwed, which creates additional compressive stress and distributes a tightening torque proportionally till the acceptable manual tightening force of each of telescopically located bolts.

EFFECT: improving productivity and reducing labour intensity of the connection of the structural elements without using any complex tightening devices.

1 dwg

Description

The invention relates to the field of general and special heavy engineering and can be used in all areas of industrial production to ensure the connection of highly loaded elements of mechanical structures.

A known method of mechanical detachable connection of machine parts using bolts (1), as well as a threaded pair "stud-nut" (2).

The disadvantage of this method is the increased diameter of the bolts and studs to create a highly loaded connection of parts due to the large shear stresses arising from the moment of twisting.

Partially indicated drawback is deprived of the method of tightening a highly loaded connection using the device ® "HYTORC" (3), which consists of:

- studs with two threaded sections;

- a double-sided threaded sleeve with two splined crowns, one of which with internal splines is designed for pairing with a key when tightening the connection, the second - with external splines for pairing with a washer;

- a nut screwed onto a threaded sleeve having projections for interfacing with a key when tightening the connection;

- washers on which the end face of the nut rests while tightening the connection and having an internal spline rim mating with the outer rim of the threaded sleeve.

The tightening method is carried out in the following sequence: the threaded sleeve with the washer mounted on it is screwed onto the pin all the way, then the pin, together with the sleeve through the hole of one of the parts to be joined, is screwed into the threaded hole of the second part until the washer abuts against the surface of the first part, then onto the sleeve the nut is screwed all the way into the washer, after which a wrench is installed on the inner spline crown of the threaded sleeve and on the nut ends of the nut, turning the nut relative to the threaded sleeve, creating the required amount of tightening the connection of parts.

The disadvantages of this method are the complexity and high complexity of manufacturing a device for tightening, as well as the dimensions of the structure as a whole.

The problem to which the claimed invention is directed is to develop a method for connecting highly loaded parts by eliminating the use of complex tightening devices, wrenches and crane equipment.

This is achieved by the fact that with this method an additional compressive stress is created in the loaded bolt with the help of additional telescopically located bolts screwed into the threaded coaxial holes of the previous bolts large in diameter, proportionally distributing the total tightening torque to an acceptable manual tightening force of each of the telescopically located bolts.

The proposed method is new: the difference from the prototype is the use of telescopic thrust bolts that stretch the smooth part of the previous bolt to a partial calculated elongation of the bolt in the connection, which allows you to tighten the bearing bolt to the stop with an ordinary wrench and create the necessary tightness in the threaded connection.

The set of essential features of the invention leads to a new technical result - the exclusion of special complex tightening devices, wrenches and crane equipment.

The proposed method is implemented using the design shown in the drawing and consisting of the connected elements 1 and 2, and the main bearing bolt 4 is screwed into the threaded hole 3 of the connected element 2, the additional loading bolt 6 is screwed into the threaded coaxial hole 5, inside it there is a threaded coaxial hole 7, into which an additional fixing bolt is screwed 8. In the connected element 1 there is a through hole 9.

The proposed method is as follows: a screw 4 is screwed into the thread of the connecting element 2 through the hole 9 of the connected element 1, an additional load bolt 6 is screwed into the screw hole 5, compressing the thread of the bearing bolt 4, then screwed into the threaded coaxial hole 7 of the additional load bolt 6 additional fixing bolt 8, compressing the thread of the additional loading bolt 6. Thus, the loading bolt 6 and the fixing bolt 8, compressing each other, create the necessary threaded interference, which prevents the turning of the bearing bolt 4 at high loads.

Thus, the proposed method and design of a highly loaded connection simplify the method and reduce the dimensions of the device, which eliminates the use of special tightening devices, wrenches.

Information sources

1. GOST7805-70 Hexagon head bolts of accuracy class A. Design and dimensions.

2. GOST22043-76 Studs for parts with smooth holes. Accuracy class A. Design and dimensions.

3. Patent No. DE102009023518 (A1) from 2008-07-16.

Claims (1)

A method of tightening a highly loaded threaded connection of parts consisting of connected parts and a bearing bolt, characterized in that an additional load bolt is screwed into the connecting parts of the bearing bolt, into which an additional fixing bolt is screwed, which creates additional compressive stress and proportionally distributes the total tightening torque to an acceptable manual the tightening forces of each of the telescopically located bolts.

Images