This paper introduced the planning layout, equipment composition, process flow and application prospect of the workstation through survey and research on the CMT arc welding workstation of the new dual-machine coordinated robot with positioner. In combination with the application description of the emerging technology of arc welding quality tracing system and arc welding visual guidance system in arc welding process, this paper expounded how to solve the problems of low robot utilization rate, low welding efficiency and poor control of weld quality of traditional arc welding workstation. The purpose of improving and optimizing of arc welding process, in-depth research and development has been realized, and the efficiency and intelligence of arc welding workstation have been improved.

To solve the problems existing in the selection method of typical test conditions of the traditional load spectrum, this paper explored the potential relationship between process parameters by fuzzy clustering analysis, and realized the classification and primary selection of operating conditions data, meanwhile, the fuzziness of the classification process was fully considered and the subjective randomness of the preliminary selection of the scheme was avoided. On the basis of the preliminary selection results, the Analytic Hierarchy Process (AHP) was introduced to comprehensively consider the 4 comprehensive evaluation indexes, namely, the typicality and comprehensiveness of the selection of test conditions, the economy of the test and the amount of spectral data. The hierarchical structure model of the system was established, and the representative test conditions were selected by combining qualitative analysis and quantitative calculation, thus improving the scientificity and systematization of the selection of typical test conditions.

Based on the technologies of vision detection, Automated Guided Vehicle (AGV) transmission, industrial robot intelligent grasping and automatic tightening, the automatic assembly efficiency, assembly quality and flexibility of welding and adjusting door cover have been greatly improved. The multi-channel cameras were integrated on the grab, and the key feature points were identified and extracted by taking photos of the door cover and the body-in-white, and the clearance and difference of each position between the door cover and the body-in-white were calculated, and then the clearance and difference matching algorithm was adopted to calculate the best position of the door cover relative to the body in white, then the transfer robot was guided to grab the door cover to reach the best assembly position. The door cover was tightened automatically by the tightening robot carrying the tightening shaft. The door cover automatic assembly technology not only improves the assembly efficiency and quality, but also reduces the labor load and cost, and ensures the overall appearance quality of the body-in-white.

In this paper, based on the poor dimension matching accuracy of engine hood caused by the deformation of gas springs acting on the hood, through the simulation analysis of CATIA three-dimensional virtual assembly, and using MATLAB to numerically optimize the installation parameters of gas springs, reasonable design parameters of gas spring were worked out, and then corresponding design changes were made, and the assembly effect on the real vehicle was verified, controlling the dimension matching accuracy of engine hood within the target range. For the design parameters’ change law of the engine hood gas springs, the following conclusions can be drawn: (1) the more front gas springs are installed on the engine hood, and the more backward gas springs are installed on the vehicle body, the larger the elastic force ratio of gas springs is; (2) the more front gas springs are installed on the engine hood, and the more front gas springs are installed on the vehicle body, the larger its travel S is; (3) in order to improve the deformation problem of the gas springs acting on engine hood, the gas springs should be installed as front as possible on the engine hood, on account of reducing the maximum compressive force.

Bolt connection is the most commonly used connection technology in automobile industry, its connection failure is a common problem in automobiles, in particular, bolt looseness is the most common problem. Through the research on self-tapping locking bolt, it is found that it has the advantages of high connection reliability, repeated use and low system cost. Through the bolt assembly process development, the difference of torque-clamping force relationship with ordinary bolts was distinguished, the assembly process parameters were determined and reliable bolt connection was realized.

The assembling and commissioning of high voltage parts of the new energy vehicle prototype is divided into 3 steps, i.e. pre-test, test and electric test. 14 control items including power battery, motor, high voltage wiring harness, high-voltage control system, other high-voltage parts, vehicle insulation resistance, vehicle potential balancing, oil & fluids filling, commissioning preparation, commissioning procedure, were analyzed and studied comprehensively through 3 steps, forming a set of prototyping & commissioning method for high-voltage parts of new energy vehicles.

Using the traditional personnel beat calculation method usually can only calculate the approximate time, which is quite different from the actual result. This paper elaborated the principle of Methods-Time Measurement (MTM) calculation method, through the MTM analysis, accurate calculation of worders load of the welding line, at the same time introduced different kinds of feeding ports of the automobile welding line and analyzed its advantages and disadvantages. According to the calculation results of MTM, this paper proposed the optimization scheme of the worker number on the welding line and the form of feeding port to ensure the rationality of the workers number and improve the efficiency of the factory.

This paper elaborated the application trend of mechanical connection technology in automotive Body In White (BIW) manufacturing. Semi-hollow and self-piercing riveting technology as the most widely applied technology of steel aluminum connecting, its process technology parameters are crucial to BIW connection strength. This paper elaborated the semi-hollow and self-piercing riveting process and quality control method as well as 2 common quality defects of semi-hollow self-piercing rivet of BIW in mass production of automobile, analyzed the influencing factors of lack of height and rupture of closed end of rivet. By commissioning of riveting equipment and optimization of riveting process parameters, the above defects were solved, providing solution and direction to solve quality issues in BIW manufacturing.

With aluminum alloy piston of automobile engine as the research object, a thermal insulation performance analysis simulation model of plasma spraying coating was established, the influences of bonding layer material and porosity on thermal insulation performance of coating were analyzed comprehensively, and the thermal insulation performance of coating sample block was verified by test. The test results show that, the thermal insulation coating can significantly reduce the temperature of piston metal matrix, and the thermal insulation performance of ZrO2 thermal insulation layer +NiCrAlY bonding layer is the best. With the increase of porosity of bonding layer, the thermal insulation performance of coating improves, but the mechanical bonding strength between coating and matrix decreases due to excessive porosity, considering the results of thermal insulation and bonding strength, the best material for bonding layer is NiCrAlY, and the best porosity is 10%. After spraying the thermal insulation coating, the equivalent thermal stress value of the piston meets the design requirements of the product under actual working conditions.

Nano-ceramic aluminium alloy is a kind of multi-item solid material, which is based on aluminium or aluminium alloy by physical or chemical methods and composed of one or more reinforcing substances with different properties. This material not only has the advantages of high plasticity of aluminium alloy matrix, but also has the advantages of high hardness and high modulus of reinforcing particles. Therefore, nano-ceramic aluminium alloy has good comprehensive properties and can be widely used in aerospace, electronics and electric, automobiles and other fields. In this paper, a kind of in-situ self-generated nano-ceramic particles in aluminium alloy matrix by chemical method is introduced. The nano-ceramic aluminium alloy prepared by this method has the advantages of light weight, high rigidity, high strength, high fatigue resistance, high temperature resistance, and its mechanical properties are much higher than those of aluminium alloy, while maintaining good processing and manufacturing properties of aluminium alloy.

This article studied the background values of DNPH tubes, with focus on exploring the effects of different brands of DNPH tubes on the recovery rates of formaldehyde, acetaldehyde and acrolein, as well as the impacts of the same brand of DNPH tubes on the recovery rates of different aldehydes, as well as the impacts of sampling conditions on the recovery rates of aldehydes. It was found that different brands have smaller impacts on the recovery rates of formaldehyde and acetaldehyde, but greater impacts on the recovery rates of acrolein. Similarly, different sampling conditions have little impact on the recovery rates of formaldehyde and acetaldehyde, but have significant impacts on the recovery rates of acrolein.

The process design stage for stampings of the Body In White (BIW) is an important stage to improve material utilization rate. This paper elaborated in details methods to improve material utilization rate in the process design stage from 5 aspects, i.e. forming method, process supplement, sheet shape, waste utilization, and thinning rate inspection. There are relatively few studies especially in process supplement. The material utilization rate of stamping parts can be improved by optimizing the distance between the workpiece boundary line and the root of the punch fillet, the width of the drawing management surface, and the drawing parting line, this provides new ideas and approaches for improving material utilization rate.