Fig. 5.4 Production and Orders Received of Composite Boilers in 1997 Fiscal Year
Fig. 5.5 Production and Orders Received of Exhaust Gas Economizer in 1997 Fiscal Year
No specially new technologies were developed in the field of the auxiliary boiler, and the Sub Committee on Boilers of the Energy Systemcommittee, successively to 1996, achieved the questionnaire survey for ship builders and shipping companies on the monitoring system of the auxiliary boiler/exhaust gas economizer for marine use, and the future monitoring system is summarized based on these results.
5.3.3 Exhaust Gas Economizer
Eighty eight sets of exhaust gas economizer were manufactured in 1997, which is about 120% compared with those in 1996. In particular, the number of exhaust gas economizers of 2.1-3 T/H class was increased from 13 to 36 supported by the demands on tankers, showing great increase by about 270%.
Fig. 5.5 shows the number of production and the orders received of exhaust gas economizers by 8 boiler manufacturers with reference to the boiler capacity.
As for large exhaust gas economizers of forced circulation type for turbo-generators (T/G) which have been employed in VLCCs, container carriers, etc., opportunities of employment have been reduced compared with the previous year from the aspect of the economy. [Takashi KURIMOTO]
6. Shafting System
No remarkable advances were achieved in 1997 except that a large propeller was employed in 5,700 TEU container carrier. Among high-speed crafts, ships for government and municipal offices, and ships engaged in domestic waters, there were some topics including the water-jet propulsion system employed in the super high-speed mono-hull or twin-hull crafts, the turning CPP equipment mounted on a fire-fighting ship, and the turning CRP announced as a new technology. Their outlines are introduced below.
IHl, MHI and MES built large container carriers of 5,700 TEU type which are the largest class in Japan, and the first ship was delivered in October, 1997 at Kure Shipyard of IHl. The propeller employed on this ship is of 6-blade type, Φ8,750 mm in diameter, and 81 tons in weight.
The main particulars are as follows.1)
LOA x B x D： 299.9 m x 40.0 m x 23.9 m
Gross tonnage： 75,637 tons
Main engine： Low speed diesel engine
53,300 kW x 94 rpm
IHl announced the turning type Contra-Rotating Propeller System "IHl CRP-DUCK" as a novel propulsion system of cargo ships and tankers engaged in domestic waters, and started the sale. (Fig. 6.1)2) The main particulars of the propulsion system for ships of 499-749 GT are as follows.
Rated output： 1,330 kW
Rated input number of revolutions： 750 rpm
Number of revolutions of propeller： 225 rpm
Forward propeller： 4-blade x Φ2,510 mm
Rear propeller： 5-blade x Φ2,200 mm
Advantages including the energy-saving effect over 10%, improvement in the turning performance, reduction in hull vibration, and contribution to reduction in the engine room space are created as a result of fitting the propulsion system.
MHI delivered the mono-hull type high-speed car ferry "UNICON" which is highest in speed in Japan at the end of May, 1997, and the ship, as a car ferry, is engaged in the route between Hakodate and Aomori in 2 hours. The propulsion system of the ship employed 4-drive and 4-shaft system in which the main engine, the gear, and the water-jet was combined, and the water-jet system (Fig. 6.2) is equipped with the steering system and the contra-rotating system for four shafts, enabling the operation such as 4-shaft parallel and 2-shaft parallel.
