SU894449A1

SU894449A1 - Method of checking article mechanical characteristics

Info

Publication number: SU894449A1
Application number: SU792786613A
Authority: SU
Inventors: Елена Константиновна Гусева; Татьяна Александровна Лудзская; Владимир Михайлович Голощапов; Андрей Андреевич Коробов; Елена Зеликовна Коварская; Игорь Борисович Московенко
Original assignee: Ленинградский Ордена Ленина Электротехнический Институт Им.В.И.Ульянова (Ленина)
Priority date: 1979-05-11
Filing date: 1979-05-11
Publication date: 1981-12-30

Description

(54) СПОСОБ КОНТРОЛЯ МЕХАНИЧЕСКИХ ХАРАКТЕРИСТИК(54) METHOD OF CONTROL OF MECHANICAL CHARACTERISTICS

ИЗДЕЛИЙPRODUCTS

1one

Изобретение относитс к испытани м материалов и элементов конструкций , в частности к способам контрол механических характеристик изделий по параметрам их колебаний.The invention relates to the testing of materials and structural elements, in particular, to methods for controlling the mechanical characteristics of products by the parameters of their vibrations.

Наиболее близким к предлагаемому вл етс способ контрол механических характеристик изделий, заключающийс в том, что предварительно делают , выборку из партии контролируемых изделийi в издели х выборки возбуждают собственные колебани , измер ют собственную частоту колебаний, затем измер ют контролируемую характеристику разрушаюп ш методом, устанавливают значени собственной частоты , соответствующие значени м допускаемой величины механической характеристики годных изделий, при контроле изделий из партии измер ют только собственную частоту, отбраковьюают в партии все издели с собственной частотой ниже граличногоThe closest to the proposed method is the control of the mechanical characteristics of the products, which consists in the fact that a sample from a batch of controlled products is made in the sample, the oscillations are excited, the natural frequency of the oscillation is measured, then the measured characteristic is destroyed by the method, natural frequencies corresponding to the values of the permissible value of the mechanical characteristics of suitable products, while controlling products from a batch, only their own values are measured vennuyu frequency otbrakovyuayut in the party all products with a natural frequency below gralichnogo

значени . Собственные колебани возбуждают по низшим формам колебанийПvalue. Own oscillations excite the lowest forms of oscillationsP

Недостаток такого способа заключаетс в низкой точности при контроле прочности на изгиб изделий в виде пр моугольных пластин, что св зано с вли нием разброса геометрических размеров изделий на собственные колебани низших форм, характеризующихс симметрией.The disadvantage of this method is low accuracy in controlling the flexural strength of products in the form of rectangular plates, which is associated with the influence of the spread of the geometrical dimensions of the products on the natural oscillations of lower forms characterized by symmetry.

Цель изобретени - повышение точности контрол прочности на изгиб изделий в виде пр моугольных пластин за счет исключени вли ни разброса геометрических размеров изделий.The purpose of the invention is to improve the accuracy of controlling the bending strength of products in the form of rectangular plates by eliminating the influence of the scatter of the geometrical dimensions of the products.

Указанна цель достигаетс тем, что собственные колебани возбуждают по несимметричньм контурным формам. Способ осуществл етс следующим образом.This goal is achieved by the fact that natural oscillations excite in asymmetrical contour shapes. The method is carried out as follows.

Claims

From the party do a sample of controlled products. In the products, the samples emit their own high-frequency contour vibrations and measure its own frequency for 3 of each sample. The sampled products are then crushed and their bending strength is measured. According to the test results, the natural frequency values are established, which correspond to the values of the admissible bending strength of suitable products. Then, when testing products from a batch, only the natural frequency of the contour oscillations was measured according to the form that was excited in the sampling products, and all products with a natural frequency below the limit value were rejected in the batch. Example. There is a batch of 200 ferrite products in the form of plates of dimensions 1 {40 X 28 X 2.6 mm. A sample is made of it - 35 plates. Their own contour oscillations are excited by the Sound-107 device. Then these 35 plates are destroyed by bending and the dependence of the values of the natural frequencies of the plates on the breaking force is constructed. From the operating conditions of the ferrite plates, the limiting permissible value of the breaking force — 32 kg — is taken, and the boundary frequency of natural oscillations of 150 kHz is determined from the dependence established above. Next, the remaining 165 products of the batch are rejected according to the natural oscillations. Products with frequencies below 150 kHz are discarded. The application of the proposed method makes it possible to exclude the influence of the spread of 9 geometric dimensions of products on the accuracy of control. Claim Method The method of controlling mechanical characteristics of products, is that they pre-select from a batch of controlled products, they produce natural oscillations in their products, measure their own oscillation frequency, then measure the controlled characteristic by destructive methods, set the values of the natural frequency, corresponding to the permissible values of the mechanical characteristics of suitable products, while controlling products from a batch, only the natural frequency is measured, all products with a natural frequency lower than the boundary value, characterized in that, in order to increase the accuracy of control of the bending strength of products in the form of rectangular plasti by eliminating the influence of the variation of the geometric dimensions of products, the natural oscillations excite asymmetrical contours. Sources of information taken into account in the examination 1. GlagoVsky BA Low-frequency acoustic methods, control in machinHOCTpoemm. L., Mechanical Engineering, 1977, p. 171 (prototype).