Development of automatic welding system applied in subsea pipeline laying
In order to explore deep water oil and gas fields in South China Sea area, an automatic welding system applied in subsea pipeline laying has been developed, which has several features such as GMAW process, two welding carriages with dual torch, narrow gap and internal line up clamp fitted with copper backing rings. The welding carriage is specially designed for offshore application, so it is compact and lightweight. The control system of the automatic welding station is constructed on the CANOpen bus and Ethernet technologies, so the flexibility and reliability of the system are greatly improved, and the pipeline welding process also can be monitored remotely.
Automatic Pipeline Welding System with Self-Diagnostic Function and Laser Vision Sensor
Automatic welding has been used frequently on pipeline projects. The productivity and reliability are most essential features of the automatic welding system. The mechanized GMAW process is the most widely used welding process and the carriage and band system is most effective welding system for pipeline laying. This application-oriented paper introduces new automatic welding equipment for pipeline construction. It is based on cutting-edge design and practical welding physics to minimize downtime. This paper also describes the control system which was designed and implemented for new automatic welding equipment. The system has the self diagnostic function which facilitates maintenance and repairs, and also has the network function via which the welding task data can be transmitted and the welding process data can be monitored. The laser vision sensor was designed for narrow welding groove in order to implement higher accuracy of seam tracking and fully automatic operation.
Application of Model Based Predictive Control with Kalman Filter to Natural CirculationWater Tube Boiler
This paper deals with the control problem of a natural circulation water tube boiler with constraint conditions. Some linearized models for the water tube boiler are proposed around some operating points, and the model based predictive control law is adopted to control the plant accounting for constraints. In this controller, the Kalman filter is used for the state estimation, and the controller is designed based on the linearized model. The control performance of the designed controller is exemplified via some nonlinear simulations around the operation point, which show it works well.