The following Design and technical requirements are based on CCS standards:

1 Marine environmental conditions

(1) The Z propulsion arrangement is to be able to work normally at the following ship angles of inclination: heeling ±15°, rolling ±22.5°, trimming ±5° and pitching ±7.5°.

(2) The Z propulsion arrangement is to be so designed and arranged as to meet the ambient temperature conditions in 1.2.1.2, Part Three of CCS Rules for Classification of Sea-going Steel Ships.

2 Strengthening for navigation in ice

(1) For ships navigating in ice areas and granted relevant CCS class notations, their propulsion machinery and auxiliary equipment are to comply with the relevant provisions of Sections 1 ~ 3, Chapter 14, Part Three of CCS Rules for Classification of Sea-going Steel Ships.

3 Main materials and material tests

(1) The materials of shafting system and propeller of Z propulsion arrangement are to comply with the requirements of 11.1.2.2, Part Three of CCS Rules for Classification of Sea-going Steel Ships and the provisions of CCS Rules for Materials and Welding.

(2) The Z propulsion arrangement and its main parts and associated parts are to be subjected to a non-destructive material test according to the CCS Rules for Materials and Welding.

4 Control and manipulation

(1) The Z propulsion arrangement is to be controlled from the navigation bridge, the machinery control position and the local position, and a rudder angle indicator is to be fitted at such control positions.

(2) See relevant provisions of 13.1.8.3, Part Three and Chapter 1, Part Four of CCS Rules for Classification of Sea-going Steel Ships for the requirements on rudder angle indicator.

(3) If the Z propulsion arrangement has electric or electro-hydraulic power equipment of steering tuning device, spare power equipment or other emergency control measures are to be provided. If there are two or more independent Z propulsion arrangements on the ship, spare power equipment is not necessary.

(4) The time of rudder movement of Z propulsion arrangement is to be in accordance with (or equivalent to) relevant requirements of the ship Administration.

(5) The steering turning device of Z propulsion arrangement is to comply with relevant requirements of Section 1, Chapter 13, Part Three of CCS Rules for Classification of Sea-going Steel Ships on steering turning device.

5 Shaft calculation

(1) Diameters of input shaft, vertical shaft and propeller shaft of Z propulsion arrangement are not to be less than the values calculated by the formula in 11.2.2.1, Part Three of CCS Rules for Classification of Sea-going Steel Ships.

(2) For shafts where the bore is greater than 0.4 times the above-mentioned calculated value, the diameter of the shaft is to be corrected according to 11.2.3.1, Part Three of CCS Rules for

Classification of Sea-going Steel Ships.

(3) For intermediate shafts and thrust shafts outside machinery of ships with ice notation B1*, the diameter of the shaft is to be increased by 10% based on the above-mentioned calculated value.

(4) The calculation of propeller shafts of ships with ice notations B1*, B1, B2 and B3 is to comply with the provisions of 14.2.2, Part Three of CCS Rules for Classification of

Sea-going Steel Ships.

6 Couplings and connecting bolts

(1) Flange couplings are to meet the requirements of 11.3.2.1, Part Three of CCS Rules for Classification of Sea-going Steel Ships.

(2) Couplings with the torque transmitted through a key are to meet the requirements of 11.3.2.2, Part Three of CCS Rules for Classification of Sea-going Steel Ships.

(3) Keyless couplings fitted by oil shrink method are to meet the requirements of 11.3.2.3, Part Three of CCS Rules for Classification of Sea-going Steel Ships.

(4) Clamp couplings are to meet the requirements of 11.3.2.4, Part Three of CCS Rules for Classification of Sea-going Steel Ships.

(5) Coupling bolts are to meet the requirements of 11.3.3, Part Three of CCS Rules for

Classification of Sea-going Steel Ships.

(6) The setting of universal couplings is to meet the requirements of 11.3.7.2, Part Three of CCS Rules for Classification of Sea-going Steel Ships.

7 Shafting vibration calculation

(1) Shafting vibration calculation of Z propulsion arrangement is to comply with the provisions of Chapter 12, Part Three of CCS Rules for Classification of Sea-going Steel Ships and is to be submitted to the ship plan approval authority for review.

8 Propeller

(1) The strength and installation of propeller are to comply with the provisions of Section 4, Chapter 11, Part Three of CCS Rules for Classification of Sea-going Steel Ships.

(2) The design of the propellers of ships with ice notations B1*, B1, B2 and B3 is to comply with the provisions of Section 3, Chapter 14, Part Three of CCS Rules for Classification of Sea-going Steel Ships.

(3) The propeller is to be subjected to a non-destructive test and a static or dynamic (where applicable) balance test according to the requirements of 9.1.6.5 and 9.1.6.7, Chapter 9, Part One of CCS Rules for Materials and Welding.

9 Steering nozzle

(1) The steering nozzle is to comply with the provisions of Article 8, Section 1, Chapter 10, Part Ten of CCS Rules for Classification of Sea-going Steel Ships.

10 Transmission gearing

(1) The transmission gearing for Z propulsion arrangements with a transmitted power of equal to or more than 100 kW is to comply with the relevant provisions of Chapter 10, Part Threeof CCS Rules for Classification of Sea-going Steel Ships.

(2) The tightness test of the gearbox is to comply with the requirements of 11.3.7.8, Part Threeof CCS Rules for Classification of Sea-going Steel Ships.

11 Hydraulic system

(1) Hydraulic system is to comply with the requirements of 13.1.7, Part Three of CCS Rules for Classification of Sea-going Steel Ships.

(2) The hydraulic pipeline is to be subjected to a hydraulic test to a pressure of 1.5 times the design pressure. On completion of installation on board, the hydraulic pipeline along with its associated parts is to be tested to 1.25 times the design pressure for tightness.

12 Clutch

(1) The clutch is to comply with the requirements of 11.3.4, Part Three of CCS Rules for Classification of Sea-going Steel Ships.

13 Bearing

(1) Sliding bearings and rolling bearings are to comply with the design working condition of Z-type propulsion arrangement. The design and type selection of rolling bearings may be conducted by the calculation method recommended by the bearing manufacturer.

(2) The temperature of the sliding bearing is not to exceed 70°C, and the temperature of the rolling bearing is not to exceed 80°C.

14 Alarm

(1) All alarms associated with the system failure are to be indicated in the bridge.

(2) Alarm functions of Z propulsion arrangement are to include: low pressure of lubricating oil (if fitted with lubricating oil pump), high temperature of lubricating oil, low level of hydraulic oil, low pressure of hydraulic oil, high temperature of hydraulic oil (if fitted with oil cooler), too high pressure difference of hydraulic oil filter (if fitted with oil filter) and low pressure of clutch.

(3) Alarm requirements are to comply with relevant provisions of 13.1.9, Part Three and Section 2, Chapter 3, Part Seven of CCS Rules for Classification of Sea-going Steel Ships.

15 Sealing and anti-corrosion

(1) Effective sealing measures are to be taken to prevent the propeller shaft and turning gear of Z propulsion arrangement from being corroded by sea water.

(2) Effective anti-corrosive measures are to be taken to prevent underwater components from being corroded by sea water.

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