Installing hull unit on retraction tank
After welding the retraction tank and allowing sufficient time for cooling, install the hull unit as follows:
1.Clean the hull unit flange, the
2.Lay the gasket (1) on the top of the tank flange.
3.Orient the hull unit so that the bow mark (arrow) on its flange points toward the ship’s bow. Note that heading adjustment in the display unit is required if the bow mark does not face the ship’s bow.
4.For the 1200 mm transducer travel type, 11 of the 24 bolt holes on the hull unit flange have already been fitted with bolts. Insert the gasket (2) into the bolt holes of the tank flange to which these 11 bolts are fitted. Note that it is difficult to fit them after the hull unit has been placed on the tank.
5.Confirm that the
6.Coat every bolt, washer and nut with slight amount of grease to ease removal. Fit the insu- lation gasket (2) into the bolt holes of both the tank and hull unit flanges. Fasten the hull unit to the retraction tank with gasket (2), flat washers, spring washers and hex bolts. (Insulation gasket (2) and gasket (2) are used on the 1200 mm transducer travel type only.)
7.Reinforce the hull unit against vibration by extending stays to the ship’s hull from the two eye bolts at the top of the hull unit, referring to figure at the top of the next page.
Hex.Nut | Hex. Nut | |
Spring Washer | Spring Washer | |
Flat Washer | ||
| ||
Insulation Packing (1) | Flat Washer | |
Insulation Packing (2) | Insulation Packing (1) | |
Bow Mark | Insulation Packing (2) | |
Hull Unit Flange | ||
| ||
Insulation Packing (1) | Insulation Packing (1) | |
Insulation Packing (2) | ||
| ||
Flat Washer | ||
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Tank Flange | Hex. Bolt | |
Insulation Packing (2) |
| |
Flat Washer |
| |
Hex. Bolt |
|
Figure 3-6 Installation of hull unit
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