Marine Auxiliary Machinery 7E Episode 1 docx

[...]... correct chemical treatment, corrosion is eliminated in the fresh water system, without the need for expensive materials 16 Main propulsion services and heat exchangers Figure 1. 11 Scoop arrangement for motorship central cooling system Scoop arrangement for a motor ship A scoop (Figure 1. 11) designed to supply sea-water circulation through the central coolers while the vessel is underway, may be installed... stress/corrosion cracking or dezincification of brass tubes Defective tubes can be plugged temporarily Figure 1. 13 Closed feed system for a tanker (Weir Pumps Ltd) 20 Main propulsion services and heat exchangers Figure 1. 14 Example of safe packing assembly for condenser tubes (courtesy of Crane Packing) Figure 1. 15 Shell expansion joint The regenerative condenser As it expands through a turbine, as much as possible... practical terms, this means maximum recovery of the latent Figure 1. 12 Scoop system for steamship with axial flow pump 18 Main propulsion services and heat exchangers heat in steam Regenerative condensers and de-aerators are two major components in the complex feed systems which have been evolved The feed system for a tanker (Figure 1. 13) shows a superheated steam supply from two water-tube boilers... circulated through the main engine and auxiliary diesels by the pumps to the left of the engine in the sketch At the outlet, the cooling water is taken to the fresh water distiller (evaporator) where the heat is used for the evaporation of sea water From the outlet of the Figure 1. 9 Turbulent flow of a fluid Main propulsion services and heat exchangers 15 Figure 1. 10 Central cooling system evaporator,... instead of diffuser-type steam ejectors and are arranged as shown in Figure 1. 21 The pump, discharging to a separator, draws from the condenser Figure 1. 19 Vacuum retaining valve Main propulsion services and heat exchangers 25 Figure 1. 20 Figure 1. 21 First and second stage ejectors Nash liquid pump ring through the atmospheric air ejector, creating a partial vacuum of about 600 mm Hg At this stage... favoured (Figure 1. 5a) These are threaded through the thin copper fin plates and bonded to them with solder for maximum heat transfer Tube ends are fixed into the tube plates (Figure 1. 5b) by being expanded and soldered Cooling of the air results in precipitation of moisture which is removed by Figure 1. 5a Detail of charge air cooler tube arrangement Main propulsion services and heat exchangers 9 10 Main propulsion... layers also receive heat mainly by conductivity The temperature profile across an element of wall surface may be considered 12 Main propulsion services and heat exchangers Figure 1. 6 Temperature gradient between fluids Figure 1. 7 Laminar flow as approximating to that depicted in Figure 1. 6 The temperature of the hot fluid falls through its boundary layer from that of the bulk of the fluid (fh) to (fhw)... can be expanded into the tube plates at both ends (Figure 1. 3), expanded at the outlet end and fitted with soft packing at the other, or fitted with soft packing at both ends (Figure 1. 14) An expansion allowance (Figure 1. 15), provided where tubes are expanded into tube plates at both ends, may take the form of a shell expansion joint Tubes are prevented from sagging by a number of mild steel tube support... valves and filters and a short length of piping Figure 1. 10 shows a complete central cooling system in which all components are cooled by fresh water The three sections are (1) the sea-water circuit; (2) the high temperature circuit; and (3) the low temperature circuit The duty sea-water pump takes water from the suctions on either side of the machinery space and after passing through the cooler it... (Figure 1. 17) More recent designs have the difrusers arranged externally and the vapour condenser shell is somewhat lighter in construction Horizontal and vertical arrangements can be found and some units are arranged as combined air ejectors and gland steam condensers Horizontal single element two stage air ejector An air ejector which has been commonly used, is shown schematically in Figure 1. 18 The . MA 018 01- 20 41 First published 19 52 Reprinted 19 76 ,19 79 Second edition 19 55 Sixth edition 19 83 Third edition 19 63 Reprinted 19 87 Fourth edition 19 68 Seventh edition 19 95 Reprinted 19 71, 1973 . and systems 17 6 7 Auxiliary power 214 8 The propeller shaft 245 9 Steering gears 286 10 Bow thrasters, stabilizers and stabilizing systems 314 11 Refrigeration 333 12 Heating,. Publication Data Marine Auxiliary Machinery - 7 lh rev. edn I. McGeorge, H. David 0623.8 Library of Congress Cataloguing in Publication Data McCeorge, H. D. Marine Auxiliary Machinery/ H.