Development Of Automatic Equipment For Circumferential Welding Of Oil Cylinder In Hydraulic Flipping Mechanism

The hydraulic flipping mechanism is widely used in the cab flipping system of heavy trucks.It has the advantages of smooth transmission,safety and reliability,etc.Its key component,the oil cylinder,is welded by the cylinder head and the cylinder barrel,and the welding quality directly affects the flipping performance of the cab.At present,the production of oil cylinders in enterprises is still mainly in the stage of manual welding,which has disadvantages such as inefficiency,poor quality,lack of security and other shortcomings.This paper aims at developing a kind of equipment which is suitable for the automatic circumferential welding of oil cylinder in hydraulic flipping mechanism according to the needs of enterprises,so as to help enterprises in their digital transformation in today’s intelligent era.Firstly,the existing issues of the manual welding of oil cylinder were studied,and the overall design scheme of the equipment was made clear according to the welding properties of the cylinder head and the cylinder barrel as well as the technical demands made by the enterprise,mainly including the mechanical structure design and control system of the execution parts of the automatic circumferential welding function design,in which the control system is composed of pneumatic transmission system and electrical control system.Secondly,the mechanical structure of equipment for automatic circumferential welding is designed in detail using the software Solid Works in according to the execution function,which mainly includes the cylinder head clamping mechanism,cylinder barrel pressing mechanism,rotating support mechanism,clamping detection mechanism and the main frame of the equipment,through computations and with the actual working situation to select the appropriate moving parts such as the air cylinder,servo motor and ball screw.At the same time,in order to confirm the rationality of the design,the static analysis and modal analysis of rotating support mechanism and main frame of equipment were performed by ABAQUS,a finite element analysis software.Then,according to the control requirements of the automatic circumferential welding equipment,the circuit schematic of the pneumatic transmission control system is designed,while the FX5U-80MT/ES is selected as the main CPU of the PLC in the hardware design of the electrical control system,and the input and output addresses of the PLC are reasonably distributed,thus completing the design of the main circuits and auxiliary circuits,including the design of the rotary servo control circuit and deviation detection circuit,etc.in the software design,use the software GX Works3 of PLC from Mitsubishi to complete the main program,rotary servo control program,adjustment servo control program and for the programming of the early warning signal control program,etc.the visualization of the interactive control interface using HMI for the host computer,which improves the interactivity of the equipment.Finally,according to the design of assembly to get the automatic circumferential welding equipment entity.After the commissioning,the comprehensive ability of the equipment was evaluated.It can be known by welding the same number of oil cylinders.The efficiency of automatic welding has increased by more than 37%compared with manual welding,and as the number of welding increases,the efficiency increases more obviously;the weld defect detection and oil leakage detection experiments on the oil cylinder show that the qualified rate of the automatically welded oil cylinder is 97.5%,which is higher than 96%required by the enterprise;the concentricity deviation of the oil cylinder is used for the process capability verification of the equipment,and the calculated C_pk value is 1.38 greater than 1.33,which satisfies the stable production requirements of the enterprise.