58.25-85—Special requirements for tank vessels.
(b)
On each tank vessel of 10,000 gross tons or over, the main steering gear must comprise two or more identical power units that comply with § 58.25-10(e)(2).
(c)
Each tank vessel of 10,000 gross tons or over constructed on or after September 1, 1984, must comply with the following:
(1)
The main steering gear must be arranged so that, in case of loss of steering capability due to a single failure in any part of the power actuating system of the main steering gear, excluding seizure of a rudder actuator or failure of the tiller, quadrant, or components serving the same purpose, steering capability can be regained not more than 45 seconds after the loss of one power actuating system.
(ii)
At least two identical hydraulic-power actuating systems, which, acting simultaneously in normal operation, must comply with § 58.25-10(b)(2). (When they must so comply, these systems must be connected. Loss of hydraulic fluid from one system must be capable of being detected, and the defective system automatically isolated, so the other system or systems remain fully operational.)
(3)
Steering gear other than hydraulic must meet equivalent standards to the satisfaction of the Commanding Officer, Marine Safety Center.
(d)
On each tank vessel of 10,000 gross tons or over, but less than 100,000 deadweight tons, the main steering gear need not comply with paragraph (c) of this section if the rudder actuator or actuators installed are non-duplicated hydraulic and if—
(2)
In case of loss of steering capability due to a single failure either of any part of the piping systems or in one of the power units, steering capability can be regained in not more than 45 seconds.
(e)
On each tank vessel of less than 70,000 deadweight tons, constructed before, and with a steering-gear installation before, September 1, 1986, and on an international voyage, the steering gear not complying with paragraph (c) (1), (2), or (3) of this section, as applicable, may continue in service if the steering gear has a proved record of reliability and is in good repair.
(f)
Each tank vessel of 10,000 gross tons or over, constructed before, and with a steering-gear installation before, September 1, 1984, must—
(1)
Meet the applicable requirements in §§ 58.25-15, 58.25-20(c), 58.25-25 (a), (d), and (e), and 58.25-70 (e), (h), (i), and (j);
(2)
Ensure working access to machinery and controls in the steering-gear compartment (which must include handrails and either gratings or other non-slip surfaces to ensure a safe working environment in case hydraulic fluid leaks);
(3)
Have two separate and independent steering-gear control systems, each of which can be operated from the pilothouse; except that it need not have separate steering wheels or steering levers;
(4)
Arrange each system required by paragraph (f)(3) of this section so that, if the one in operation fails, the other can be operated from the pilothouse immediately; and
(5)
Supply each system required by paragraph (f)(3) of this section, if electric, with power by a circuit that is—
(ii)
Connected in the steering-gear compartment to the circuit supplying power to the power unit or units operated by that system; or
(iii)
Connected directly to the busbars supplying the circuit for its steering-gear power unit or units at a point on the switchboard adjacent to that supply.
(g)
Each tank vessel of 40,000 gross tons or over, constructed before, and with a steering-gear installation before, September 1, 1984, and on an international voyage, must have the steering gear arranged so that, in case of a single failure of the piping or of one of the power units, either steering capability equivalent to that required of the auxiliary steering gear by § 58.25-10(c)(2) can be maintained or the rudder's movement can be limited so that steering capability can be speedily regained in less than 10 minutes. This arrangement must be achieved by—
(2)
Fast-acting valves that may be manually operated to isolate the actuator or actuators from the external hydraulic piping, together with a means of directly refilling the actuators by a fixed, independent, power-operated pump and piping; or
(3)
An arrangement such that, if hydraulic-power actuating systems are connected, loss of hydraulic fluid from one system must be detected and the defective system isolated either automatically or from within the pilothouse so that the other system remains fully operational.