RU183766U1 - Device for determining the shear strength of welded joints with an overlap of a plate and a rod - Google Patents

Abstract

The invention relates to devices for determining the shear tensile strength (PPS) of welded lap welded joints (OSSV) of plates and rods under static compression, in particular, to devices applicable in determining the PPS of OSSV. The device consists of a cage in the form of a direct prism with a rectangular groove and a cylindrical hole in which a sample of overlap welded joints is placed, as well as a sealing plate that prevents deformations of the OSSV and installed between the holder and OSSV, providing a clean shear during compression of the "holder + OSSV" slice) welded joint. Effect: reducing the impact of the eccentricity of the application of the load on the accuracy of determining the limit of faculty; reduction of material consumption for the manufacture of OSSV. 1 tab 6 ill.

Description

The utility model relates to devices for determining the shear tensile strength (PPS) of welded joint (CC) lap (OSSV) samples of plates and rods under static compression, in particular, to devices applicable in determining the OPSS OPS.

Known regular captures (devices) of explosive machines and the shape of the samples (GOST 6996-66) for testing SSSV and determining the PPP under static tension. Devices, as a rule, based on the use of the effect of wedge-shaped compression of the OSSV and axial application of load to each of the elements of the sample, are used to compress 2 × (50 ÷ 80) mm of the length of the sample - this determines the total length of the OSSV in 200 ÷ 300 mm.

The disadvantages of the devices and the shape of the samples (Fig. 1a) are: the influence on the accuracy of the determination of the SPS of the weld (SS) of the eccentricity (Fig. 1b) of the application of tensile loads to the OSSV and its plastic deformation (Fig. 1c); significant consumption of material for the manufacture of OSSV.

The technical effect of the proposed utility model is: reducing the influence of the eccentricity of the application of the load on the accuracy of determining the limit of faculty; reduction of material consumption for the manufacture of OSSV.

The specified technical effect is achieved by the fact that the device for determining the shear strength, consisting of a cage in the form of a direct prism with a rectangular groove and a cylindrical hole, into which the OSSV is placed, as well as a sealing plate installed between the holder and the OSSV, which prevents deformation of the OSSV, provides the compression of the system "clip + OSSV" net shift (slice) of the secondary school.

In FIG. 1a shows the plan, facade, and cross-section of the SIRS. In FIG. 1b and FIG. Figure 1c shows the zones of the NW before and after application of the load under the normal, normative position of the NNSW in the grips of a tensile testing machine.

In FIG. 2 shows a general view of the SIRS (Fig. 2a) and the projection of the SIRS on the plane (Fig. 2b), where: 1 - the core of the SS; 2 - plate SS; 3 - US.

In FIG. 3 shows projections on the plane of the holder for testing, where: A, C, H are the dimensions of the holder; d is the diameter of the through cylindrical hole for the rod OSSV; A, c _in , h _in - the dimensions of the prismatic groove for the OSSV plate.

In FIG. Figure 4 shows a vertical section and a plan of a holder with an OSSV located in it, where: 4 is a sealing plate that prevents deformations of the OSSV plate with its small thickness, δ << d.

After performing the tests by compressing the OSSV located in the holder, the following are determined:

F _p is the breaking load;

τ _in - faculty secondary school:

When testing the SIRS, similarly to the normative method, due to the eccentricity of the application of active and reactive forces (see Fig. 5), in addition to tangential stresses in the plane of the NL, normal stresses σ appear (Fig. 5, ep. Σ along the length of the NL), perpendicular to the plane of the plate , and the SS experiences a complex stress state, which is reflected in the evaluation of the shear strength.

The maximum normal stresses maxσ are determined from the condition of equality of the moments of the eccentricity M _e and the reactive moment M _{p of} efforts along the vertical plane of contact of the cage and the SIRS:

Ratio

allows to evaluate the effect of maxσ on the strength of the secondary school:

at k <0.05 ÷ 0.10, the effect is very small and can be neglected in engineering calculations;

at k <0.10 ÷ 0.25, the influence is significant and can be taken into account by a corresponding increase in the safety factor, for example, by increasing the length of the secondary school;

for k> 0.25, the assessment of the strength of the secondary school should be performed according to the corresponding theory of strength.

Example. To study the strength of the secondary school, samples were made of steel plates (St-3, δ = 10 mm) and lap welded reinforcing bars (St-5, d = 12 mm) of a periodic profile. Welding was performed on a laser robotic complex using a fiber laser LS-5 (IPG Photonics / IRE-Pole) with continuous radiation in a shielding gas (argon).

In FIG. 6 shows: a) the sample in the device during the shear test in the R-10 testing machine; b) general view of the samples after testing.

In the table. 1 presents the test results of 6 samples of SIRS.

Thus, due to the use of the device and loading of the cage + OSSV system with static compression: the influence of the eccentricity of the application of the load on the accuracy of determining the PPP is reduced; 2.5 ÷ 4.0 times reduced material consumption for the manufacture of SSSV by reducing their size; The fleet of used testing machines is expanding.

A device for determining the TPS OSSV plate and rod under static compression can be used to determine the tensile strength of a shear in educational, scientific and industrial laboratories.

Device for determining the shear strength of welded joints with an overlap of a plate and a rod

Claims (1)

A device for determining the shear strength of shear samples of lap welds (OSSV) of a plate and a rod, consisting of a clip in the form of a direct prism with a rectangular groove and a cylindrical hole in which the OSSV is placed, as well as a sealing plate that prevents deformation of the OSSV and installed between the holder and OSSV, provides a clean shear (shear) of the welded joint during compression of the ferrule + OSSV system.

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