SU1752475A1 - Method for riveting packages from sheet parts - Google Patents

Abstract

Use: assembly production, riveting of light alloy construction elements with a sheet thickness of 0.125-0.4 rivet rod diameter. SUMMARY OF THE INVENTION: A hole with a diameter of 0.3 mm smaller than the diameter of the rivet rod was drilled in a package of parts to be joined. Stamped tapered nest with a diameter larger than the base of the cone, equal to the diameter of the mortgage head. Drill a hole to a diameter corresponding to the diameter of the rivet rod. Install the rivet with a convex head. In the process of forming the locking head, the tapered socket is deformed in the direction of the inset head until it aligns with the surface adjacent to the inset head. The method provides the alignment of tension on the package thickness, elimination of the weathe, increasing the strength and quality of the surface 3 silt

Description

The invention relates to riveting, in particular to methods of riveting, used in the assembly of structural elements of light alloys with a sheet thickness of 0.125-0.4 rivet diameter, mainly in the aerospace and shipbuilding industry.

The aim of the invention is to increase the life of the riveted joint and the quality of the outer surface of packages of sheet elements with a thickness of 0.125-0.4 of the diameter of the rivet shank.

The goal is achieved by drilling a hole with a diameter of 0.3 mm smaller than the diameter of the rivet into the package of parts to be joined. In the bag, the socket is made coaxially with a cone-shaped hole. The hole is drilled to the required diameter, a rivet is inserted with a protruding mortgage head, and the rivet rod is deformed to form a closing head.

New is that the tapered socket is made from the side of the mortgage head coaxially to the hole in the bag, the diameter of which is equal to the diameter of the mortgage head, and the depth of the socket is 0.016-0.09 diameter of the rivet rod. In the process of upsetting the rivet rod under the action of the closing head, the package of parts is deformed in the direction opposite to the formation of a weft by pressing the nest until the package is pressed to the surface of the rivet head.

Fig. 1 shows the initial state of the parts after the rivet has been installed; Fig 2 - the intermediate stage of the riveting process; on

FIG. 3 - the final stage of the riveting process.

The method is as follows.

The elements to be joined, for example, two sheet metal parts, assemble into package 1 and drill a hole in it, 0.3 mm in diameter less than the diameter of the rivet rod. After that, the conical recess is made in both parts to be joined using a die and a punch is used to stamp the conical socket 2, the diameter of the base of the conical socket being equal to the diameter of the mortgage head. The depth of the stamped nest is chosen from the following considerations: the depth of the nest should be equal to the size of the weave-riveted package and is determined by the formula;

w ,, Ml (, di), (1)

where W is the value of the inlet, mm;

K 1 - cone component of tension over package 1 thickness

d - rivet rod diameter, mm;

h is the thickness of the package, mm;

co o is a cylindrical component of the hell in the package thickness,

To determine the boundaries of the depth interval of the nest, we substitute into formula (1) the maximum and minimum values of the packet thickness: for Lmax 2xO, 4ct

c-- L / MIM

2, 89 0.02 d

(0,8dy

, 016d, - (2)

where S is the depth of the stamped socket; at, 125d 5max L / mzks

2.89 0.0 cr (0.25d) 2

, 09 (1 (3)

After the stamped nest 2 has been formed, the hole is drilled to remove microcracks in the parts to be joined and to relieve stresses to a diameter equal to the diameter of the rivet shank. A rivet 3 is then installed in the hole and a closing head 4 is formed. In the process of forming, the closing head 4 acts on the package 1 with a force PCr. Due to the shoulder between the compressive forces RSJ from the side of the mortgage and closing heads, a moment of force is formed, counteracting to the bending moment of Mizg, resulting from the uneven deformation of the rivet rod through the package thickness. With increasing RSzh

0 5

five

about

0

five

0

5 0 5

the locking head 4 deforms the packet 1 before pressing it against the surface of the inset head, thereby preventing the formation of a tightness and equalizing the voltage in the riveted joint.

The alignment of stresses in the joint improves the quality of the external surface and the life of the joint.

The proposed method was tested under batch production conditions on samples from D16AT material in the form of a skin and a reinforcing element.

The total thickness of the bag was 1.0 mm, 2.0 mm; 3.2 mm. Rivets were used with a diameter of 4 mm alloy B65. Pre-drilling of the hole was made with a drill diameter of 3.8 mm, the final 4.1 mm. The depth of the stamped socket was made according to the thickness of the package 0.36 mm; 0.12 mm; 0.06 mm. Riveting was carried out both by pressing and impact methods. The amount of tightening in all cases did not exceed the permissible value of 0.05 mm,

The use of the proposed method leads to the alignment of tension on the package thickness, to the elimination of the weft, and as a result, to an increase in the strength characteristics of riveted joints and on the quality of the outer surface, thus reducing the drag coefficient of the aircraft.

Claims (1)

Invention Formula The method of riveting packages of sheet metal parts, including the formation of holes with a diameter smaller than the diameter of the rivet rod in the joined parts, the formation of a stamped tapered socket, coaxially with a hole with a diameter larger than the base of the cone equal to the diameter of the fixed rivet head, reaming the hole to a diameter corresponding to rod rivet, insertion into the hole from the side of the conical socket of the rivet and the formation of a closing head, characterized in that, in order to improve the surface quality and resource while joints with riveting of parts with a thickness of 0.125-0.4 of the diameter of the rivet rod, holes are made with a diameter of 0.3 mm less than the diameter of the rod of the rivet, rivet is performed with a convex head, the depth of the socket is equal to the amount of riveting, and during the formation of the locking head, the tapered socket is deformed in the direction of the inset head until it aligns with the surface of the part adjacent to the inset head. / l 4 / jys No. &. fy $  fa ff L fa J, fa.i