Gasmizer Manual - Submarine Manufacturing and Products Ltd

March 09
APPENDIX C - COOLING WATER HEAT EXCHANGER
SEAWATER/FRESHWATER TYPE FG 1603877-5: PART GE098
Description
1. The heat exchanger consists of a shell, tube stack and end covers sealed by ‘O’ ring seal held in
place by an end cover, which secures the seal against three faces; the body, the tube plate and the
end cover.
2. Shell - Comprises an aluminium casting, fully machined to accept the tube stack.
3. Tube Stack - Comprises naval brass tube plates, between which are the tubes. Theses are punch
expanded and bonded in place by soldering. The tube material is cupro-nickel. The freshwater is
guided over the tube by a series if baffles arranged along the length of the tube stack. Baffles are
of the radial flow type and constructed from aluminium.
4. End Covers - The end covers are manufactured in gun metal and incorporate the cooling seawater
inlet and outlet connections.
5. O-Ring Seals - The material of the O-Ring seals is nitrile.
Installation
1. It is important that air is kept out of the system, particularly on the fresh water side. Aerated water
can cause erosion of the tubes. Heat exchange should be piped for counter flow. The cooling
water inlet should be on the lower connection and outlet the upper connection. Always circulate at
the recommend sea water and fresh water flows. Excessive flow can also cause corrosion and
erosion.
Duty Flow Fresh Water 10 imp galls/min
Sea Water 16 imp galls/min
Pressure Fresh Water 17 lbf/in 2 1.3 Bar
Sea Water
Heat Exchange Rate
Connection
Weight
30 to 45 lbf/in 2 2 to 3 Bar
1500 BTU/min
1 1/4” BSP
18Kg
OM002 Rev 5 Page 142 of 168 Chap 9