Wet Welding Platform Design based on Ultrasonic Sensor
The research platform for underwater wet welding is designed and high frequency ultrasonic sensor is put into use, The research platform comprises four independently movable shafts which names as X, Y, Z and A axis, The four axes are driven by servo motor and stepping motor, The features of both servo motor and stepping motor are analyzed at first, and then the relationship between the moving speed and controlling precision among different shaft is discussed, control program is given out based on ADT8940A1 PCI four-shaft bus control card after the shafts running parameters have determined, With the help of high-frequency underwater ultrasonic sensor, high-precision ranging experiments are carried out on the base of a hybrid digital signal process method combined band filter and Wavelet transform (WT), satisfied results are achieved in distance detection experiments with related coefficients method, results will be used in seaming tracking later.
Automatic underwater arc welding seam-tracking system based on flux-core wire and rotating arc sensor
The wet underwater arc welding seam-tracking technology based on rotating arc sensor is introduced. An experimental system used to study the welding automation is established and welding parameters are found out at first for flux core arc welding based on experiments. The approach of calculating the welding current integration differences is adopted here to determine the welding-gun horizontal bias and vertical bias. Manifold digital signal process methods are performed on all sampled noisy signals to improve stability and reliability of results; Analysis on massive experimental data revealed that both horizontal bias and vertical bias can all be clarified clearly by this way; Further more, a manipulating system is carried out on above conclusions, and two kinds of different manipulators-Fuzzy controller and hybrid PID controller are designed separately to adjust the horizontal deviation and vertical deviation. The results of verifying tests approved the effectiveness of all above work.
Composite monolayer fabrication by an arc-spray process
A single layer (monotape) technique for fabricating complex high-temperature tungsten-fiber-reinforced superalloy composites is proposed. The fabrication of sheets of arc-sprayed monotape 38 cm wide and 122 cm long has been demonstrated. Composites fabricated using the method are shown to have equal tensile strength and a cleaner matrix than composites fabricated from powder metal cloth monotapes, and the present technique is less expensive than the powder metal fabrication techniques.