Iranian Classification Society Rules

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Section 2 Machinery Installations and Electrical Equipment for Self-propelled Units


201. General


1. Application


For the Machinery installations and electrical equipment for self-propelled units, in addition to the requirements in Sec 1 and the relevant requirements in Pt 5 and Pt 6 of Rules for the Classification of Steel Ships, the requirements in this Section are applied.


2. Means are to be provided whereby normal operation of propulsion machinery can be sustained or restored even though one of the essential auxiliaries becomes inoperative. Special consideration is to be given to the malfunction of:

(1) a generator set which serves as a main source of electrical power;

(2) the sources of steam supply;

(3) the arrangements for boiler feedwater;

(4) the arrangements which supply fuel oil for boilers or engines;

(5) the sources of lubricating oil pressure;

(6) the sources of water pressure;

(7) a condensate pump and the arrangements to maintain vacuum in condensers;

(8) the mechanical air supply for boilers;

(9) an air compressor and receiver for starting or control purposes; and

(10) the hydraulic, pneumatic or electrical means for control in main propulsion machinery includ- ing controllable-pitch propellers.

However, the Society, having regard to overall safety considerations, may accept a partial reduction in capability from full normal operation.

3. Conditions of inclinations


In addition to the requirements in 102. 2, main propulsion machinery and all auxiliary machinery essential to the propulsion and for the safety of the unit are, as fitted in the unit, to be capable of operating under the static conditions required by 101. 2 (1) and the following dynamic conditions :

(1) column-stabilized units : 22.5° in any direction.

(2) self-elevating units : 15° in any direction.

(3) surface units : 22.5° rolling and simultaneously pitching 7.5° by bow or stern.

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The Society may permit deviation from these angles, in consideration of the type, size and serv- ice conditions of the unit.


202. Boiler


1. Water tube boilers serving turbine propulsion machinery are to be fitted with a high-water-level alarm.


2. Every steam generating system which provides services essential for the propulsion of the unit is to be provided with not less than two separate feedwater systems from and including the feed pumps, noting that a single penetration of the steam drum is acceptable. Means are to be provided which will prevent overpressure in any part of the systems.


203. Control and monitoring for propulsion machinery

Where propulsion machinery spaces are ing systems are to be constructed and

normally unattended during transit, the control and monitor- installed in accordance with the applicable requirements in

Pt 6, Ch 2 of Rules for the Classification of Steel Ships.


204. Astern tests

In addition to the carried out.

1. In the astern trial,


requirements in 109. for machinery installations, the following tests are to be an order for full astern is issued while the unit is running ahead at the speed

specified in Pt 3, Ch 1, 120. of operation from ahead run to full

Rules for the Classification of Steel Ships, whereby reversing astern run is to be carried out as fast as possible. In this case,

astern operation is to be continued until the astern speed (rotational speed in rpm) is stabilized for

diesel units, or for the period of 15 minutes after the order of astern for steam turbine units, gas turbine units and electric propulsion units respectively, whereby the astern performance and stopping performance are to be verified and the test results recorded are to be available on board for the use as a guidance for unit manoeuvres.


2. In units having multiple propellers, the unit navigating and maneuvering performance with one or more propellers inoperative is to be verified, as well as the test results recorded are to be made available on board for the use as a guidance for unit manoeuvres.


3. When the units provided with supplementary means for maneuvering or stopping, performance test for such means is to be carried out, and the test results are to be available on board for the use as a guidance for unit manoeuvres. image

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