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[en] This paper describes a remote controlled dual arm manipulator system cutting a still pipe at high place. Remotely cutting work is one of the tasks with complicated working conditions. An overview and comparison of cutting techniques for piping is given. These include a plasma arc, arc saw, linear-shaped explosive charge, and 'conventional cutting methods' for metal cutting. The dual arm manipulators consist of two LBR iiwa 14 R820's. LBR iiwa is a light weight 7 DOF articulated manipulator that weighs 29.5 kg with a payload capacity of 14 kg, and is able to move precisely with +/-0.1 mm repeatability. It assembles parts delicately and detects external forces using integrated torque sensors
[en] Due to the high degree of required dimensional accuracy in its manufacturing, repairing of lining pipes with flanges requires a long installation period. With the conventional method, we have to wait more than three weeks to start lining installation after the start of onsite construction, because pipe dimensions are determined onsite then lining installation is conducted at shop. It causes prolongation of the onsite installation period. Therefore, we have tried to improve the dimensional accuracy in its manufacturing by applying three-dimensional as-built laser measurement device which enables high precision measurement. In addition, we established a new process from manufacturing to installation. As a result, we achieved successful shortening of onsite lining pipe repairing period. However, there are still some conditions and points to be dealt with to apply this method to the actual construction. We organize them and provide important points in this paper. (author)
[en] Materials used for steam piping of power plants are exposed to high temperatures and high pressures over long periods of time. As a consequence, forged Grade 91 alloy steel is commonly chosen to meet these demands. However, complicated structures such as a valve body are often machined from large forged blocks resulting in long machining time and the material weight being heavy. Therefore, by manufacturing a valve body with near net technology, both the time and material weight can be reduced. This paper will present 1) a survey of the dimensions of a valve body HIPed to a near net shape, 2) an investigation of the mechanical properties of Grade 91 powder, 3) a comparison of the structure of a HIPed product and a forged product, 4) The machining time and material weight of a near net shaped (NNS) product by HIP compared to a forged product. This paper will illustrate that the NNS product was able to reduce the machining time by 30% and the material weight by 40% less than when machining from a forged product.