Methods for evaluation of mechanical stress condition of materials

Abstract

Abstract. Primary attention is given to the following methods: method by drilling cylindrical holes (drill method) and integrated ultrasonic method using volume (longitudinal and transverse), surface, and sub-surface waves. Drill method allows determination of residual mechanical stress in small depth of material surfaces, assessing type, size, and orientation of principal stresses. For the first time, parallel studies are carried out of mechanical stress in materials using the electroacoustic effect of volume, surface and sub-surface waves on the one hand, and effective mechanical stresses on the other. The experimental results present electroacoustic coefficients for different types of waves in the material of gas pipeline tube of 243 mm diameter and 14 mm thickness. These are used to evaluate mechanical stresses in pipelines, according to active GOST standards.

Study on the Strengthening Effect of Excitation Magnetic Field on Stress-Induced Magnetic Signal of X80 Steels

“…At present, the traditional methods for pipeline axial stress inspection include the small hole method [5], the X-ray diffraction method [6], and the ultrasonic stress detection method [7]. However, the small hole method can cause damage to pipelines and is not suitable for stress detection of in-service pipelines.…”

Study of the Steel Heat Treatment Mode for the Purpose of Increasing the Efficiency of Ultrasonic Control

“…Failure of the connecting element under load can lead to human casualties. In the best case, a breakdown of the connecting element destroys the structure, and long-term repair of the structure leads to high economic costs, both due to the need to replace damaged parts of the structure (capital costs), and indirectly due to equipment downtime [1][2][3][4][5].…”