Automatic abrasive blasting system for large diameter pipe bends

Abstract

Abrasive blasting is an important surface treatment process. Aiming at overcoming the shortage of the manual abrasive blasting process for large diameter pipe bends, T-pipes and gas collecting tubes, this paper presents the study of automatic abrasive blasting for large diameter pipe bends. According to the requirement of blasting process of large diameter pipe bend, the 5-DOF orthogonal coordinate abrasive blasting mechanism is constructed. Due to the massive dust and serious wear, the seal and protective measures of the mechanism are fully considered. In order to maintain a reliable operation of abrasive blasting system in severe environment, an automatic control system based on PLC is designed. In order to keep a specific angle between the sand-blasting gun and the workpiece surface, which can improve the working efficiency, the surface tracking control model was constructed based on the infrared distance measuring sensors. In order to improve the measurement accuracy of the sensors, the second order linear fitting method based on the least square method was used to calibrate the infrared range sensors. The experimental results indicate that the proposed automatic abrasive blasting system has significance on improving sand blasting quality, working efficiency and environment as well as reducing labour costs.