The superior characteristics of the multi-geared diesel plant for marine propulsion has been recognized gradually. In order to fully realize the superiority of the propulsion system of this kind, clutch couplings of high-performance and high-reliability have been eagerly demanded. In such circumstances we have recently developed a double-cone type and air-operated, friction clutch with high elastic rubber coupling. Previously, with a test clutch coupling of model type (rated capacity of 500 ps) we have carried out simulately various tests to study performance and endurance characteristics. Through the test various technical data have been obtained ; such as vibration and alignment-characteristics, frictional characteristics of some clutch-lining materials and thermal endurance limit on clutch drum. Based on these experiences and data, a clutch coupling of enlarged capacity for practical use (rated capacity of 10, 000 ps) was designed and manufactured for trials. Also this clutch was assembled in a test shafting line in our shop, simulated to a practical and typical marine propulsion system. The clutch was loaded with a hydraulic dynamometer and driven by a diesel engine of KA-WASAKI-M·A·N V8V 40/54. As results, followings have been confirmed : (1) This clutch coupling has enough capacity for rated torque transmission, and possibility to improve astern manoeuvre by clutch application. (2) This clutch coupling can be easily controlled remotely or antomatically as well as manual operation and it can damp out the torsional vibrations in the entire operating range. (3) Additionally this clutch coupling can be manufactured with reasonably low cost.
Recently, adoption of high performance reheat turbine plants is increasing for the huge ships. In our company, KAWASAKI UFR type marine reheat boiler has been developed for such as the KAWASAKI UR plant. This paper discusses about the outline of design and actual experiences of our steam temperature control (STC) system. UFR boiler is constituted of single radient furnace and three gas paths system where gas passage is divided by partition water walls into a superheater path, a reheater path and a by-pass economizer path with control dampers arranged at each outlet of the paths. In reheat condition, both the superheater and reheater steam temperatures are controled by three dampers, and in non-reheat condition superheater steam temperature is controled by operating the by-pass damper. The protection of reheater from overheating when there is no reheat steam flow through the reheater during astern or port use condition is carried out by adoption of the double shut dampers which shut out the gas leakage through reheater path. At the designing of this STC. system, we take into consideration of the independent control of the superheater and reheater temperature without interaction and the system matching to the boiler and turbine operation. We hereupon introduce two policies of “Non-interacting control to load disturb-ances” and. “Non-interacting control to set point changes of steam temperature” for the first item. And also we provide the suitable sequential and program control in the case of changing over between reheat and non-reheat condition for the second item. In actual operation of this boiler, highly satisfactory control results have been obtained.