Research on the Technology of Welding Manipulator in the Production of Locomotive Frame (Part 1)

1 Overview

Welding manipulator manufacturer shares with you: Welding robots occupy an important position in automated welding production, and the application of this method in the welding field of advanced western countries is becoming increasingly mature. According to China's industrial "2025" goal, the locomotive and rolling stock industry is transforming from manual semi-automatic welding to welding intelligent manufacturing. Welding robots are one of the main execution equipment for intelligent manufacturing of steel structure products. As the main equipment of welding robots, welding robots are far superior to manual welding in terms of product welding quality stability, efficiency, and appearance of welds. At the same time, welding with robots has a relatively fixed production cycle and low labor intensity. It is a necessary equipment for the development direction of artificial intelligence in the manufacturing industry.

In the locomotive and vehicle manufacturing industry, although the single beam components of the locomotive chassis and the frame frame have been introduced with a welding manipulator for more than two decades, considering the complexity of the structure of the locomotive bogie frame frame (herein referred to as the frame, the same below) Processability and importance, only a few manufacturing units are studying the robot welding process of the framework. The robot welding process has also been successfully used in our company's locomotive chassis and single beam components for many years. The company has mature robot hand welding experience.

This article focuses on the process research and application of welding manipulators carried out by our company in the welding production of a locomotive frame, in order to provide valuable reference for the subsequent process promotion of welding robots in the locomotive frame.

2. Analysis of the structure and welding process of the locomotive frame

(1) The locomotive frame is designed according to the EN15085 system. It consists of box beams such as left and right side beams, cross beams, and front and rear beams. The structural welds are distributed symmetrically along the "X" and "Y" axes, and are located at the joints between the beams: mainly T-shaped joints composed of V-shaped groove butt joints and butt joints; there are many welds and their lengths In the range of 200 ~ 500mm; the position is in the space position; according to the EN15085 system, the quality level of the welds is CPB, and the welding quality is high. After welding, UT ultrasonic inspection, MT magnetic particle inspection, and VT appearance inspection are required.

Welding Manipulator

(2) The frame material is 16MnDR low-alloy high-strength steel widely used in China's locomotive industry. The steel has a carbon equivalent Ceq of less than 0.4% and good weldability. The thickness of the steel plate ranges from 8 to 20mm. The welding process requires multiple layers and multiple passes for welding.

(3) Structural welding process content First, butt welds of the upper and lower cover plates of the side beams of the frame, the upper and lower cover plates of the middle beam, and the lower and upper cover plates of the front and rear beams. Secondly, the single-sided Y-shaped fillet welds of the side beams of the frame and the front and rear beams. Finally, a single-sided Y-corner fillet weld between the side beams of the frame and the beam slabs.

(4) Statistics of joints According to the structural form and joint statistics of the welds of the frame products, the frame requires 6 test pieces for welding work.