Home ||| Bulk Cargo ||| Planning ||| Care ||| Safety||| Self unloaders
Navigation in Ice and safety precautions - Self-unloaders procedure
The onset of Ice Accretion can be sudden and dangerous. In the North Atlantic Ocean, the transit of a cold frontal system in winter, will rapidly bring down the air-temperature, causing the vessels steel structure to cool. The driving sea spray then adheres to the ships structure, and forms ice which builds up rapidly.
The consequences are:
- Change in trim generally by the head.
- Reduction in stability.
- Blockage of air-vents, ballast tank air-pipes.
- Freezing of pipelines.
- Increase in viscosity of hydraulic oil in the systems,
- Fracturing of exposed castings made from cast iron.
- Icing of bridge windows.
- Blockage of Deck Scuppers.
If there is ice formation on the sea surface, this usually restricts the sea spray, however, ice accretion is still possible where there is high air moisture content. Ice formation of the sea surface severely restricts navigation and the vessel may become ice-bound. Forcing the ship through ice can cause damage to the hull, shipside intake grids and may damage the propeller, if attempts are made to go astern. The cooling water intakes may also become frozen, and the decision to enter an ice bound area has therefore to be carefully considered.
Fig:SELF UNLOADER BURNS HARBOR DURING ICY CONDITIONS
The boundaries of ice, the predicted shift of these boundaries, the type of ice formed e.g. grey ice, pack ice etc are transmitted in bulletins. It must be remembered that the ice boundaries can have moved since the last bulletin, and the proposed routes may be affected. The assistance of an Ice Breaker could also be required, and the vessel may have to join an ice convoy. The Master must engage an Ice Pilot for the area if available.
Preparations for Ice:
- Take additional bunkers as an allowance for manoeuvring in heavy weather and deviations due to ice and ice accretion.
- Maintain a large stock of de-icing salt on board.
- Remember that the ice accretion is possible in cold driving winds.
- Change to low sea suctions, and provide temporary steam pipes at the intakes, if permanent de-icing connections are not provided.
- Cover the mooring lines, cable drums etc with plastic covers and secure.
- Cover all exposed motors and control stands.
- In exceptional circumstances, and subject to the vessels stability, due consideration must be given to lowering the ballast tank levels, if there is a risk of the ballast freezing.
- Check the ballast air-pipes for clogging with ice, prior to any ballasting or de-ballasting.
- If ice accretion is rapid, then maintain steerage away from the spray.
- Keep both anchor shanks slightly out of the hawse-pipe, so that ice formed inside the hawse-pipe holding the anchors can be broken by heaving the anchor.
- Cover the spurling pipes.
- Cover the fairlead openings by canvas and wooden templates.
- Keep crowbars and ice-picks ready for use.
- The Crew are to be clothed according to the recommendations made in NP 100 against the wind chill diagram.
- The radar scanners are to be kept on stand by if not in use.
- Keep the bow thruster heater on for about three 3 hours before arrival, and turn them slowly every hour to ensure that the oil is warm.
- Check electrical insulation.
- Drain the fire lines, grease their expansion joints.
- Spread de-icing salt on decks.
- Cover the boom belt with canvas so that the rollers are not affected by ice accretion.
- Lower a length of manila rope in the scuppers.
- The heating coils of the emergency generator are to be on and, the tank maintained at 90% full to avoid condensation.
- With regard to the engine cooling system the manufacturers instructions are to be adhered to, and the cooling system must be fitted with a solution of water and antifreeze at the recommended ratio to provide protection down to at least, minus 40oC.
- Maintain the outside air-circulation into the engine room at the minimum required. Keep all WT doors to all spaces and all other accommodation doors closed.
- Ensure that the Fore Peak tank manually operated valves are closed, and also that all tank manholes are closed.
- Turn on the accommodation heating, and ensure that the sanitary and domestic water flow is satisfactory.
Our detail pages illustrated many safety aspects of Bulk carrier
Home page |||Bulk carrier types ||| Handling of bulk coal |||Cargo planning ||| Carriage of grain |||Risk of iron ores |||Self unloading bulk carriers |||Care of cargo & vessel |||Cargoes that may liquefy |||Suitability of ships |||Terminal guideline |||Hold cleaning |||Cargo cranes |||Ballast handling procedure |||Bulk carrier safety |||Fire fighting systems |||Bulk carrier General arrangement
Operation of sea going bulk carriers involved numerous hazards . Careful planning and exercising due caution for all critical shipboard matters are important . This site is a quick reference to international shipping community with guidance and information on the loading and discharging of modern bulk carriers so as to remain within the limitations as specified by the classification society.
Self unloader components
Function of loop & bucket belt elevators
Self unloaders various cargo handling gears
Various type boom conveyor belts - How the belt sytem practically works ?
Dealing with self unloaders stalled lift belt
Conveyor belt construction & troubleshoot guide
Conveyor belt installation guide
Conveyor belt repair & maintenence guide
Safe working practice onboard self unloading bulk carriers
Preventing conveyor belt fire onboard self unloading bulk carriers
Cargo work safety precautions
Various bulk cargoes - free flow ability
Various bulk cargoes & dealing with cargo hang ups
Dust suppression procedure & environment protection
Preparations for cargo planning, handling & stowage
Maintaining safe stability onboard self-unloading bulk carriers
Procedure for bulk cargo handling prior to and during loading
Loading operations - voyage orders, draft restrictions, various grades and rates
Loading sequence and other related considerations
Preparations for discharging & related guideline
Self unloaders discharging operation
Safety precautions for boom operation
Directing gate operation, gate problems & crew duties
Cargo holds/ tunnels cleaning, maintenance and check items
Procedure for transporting coal on self- unloading bulk carriers
It is vital to reduce the likelihood of over-stressing the ship's structure and also complying with all essential safety measures for a safe passage at sea. Our detail pages contain various bulk carrier related topics that might be useful for people working on board and those who working ashore in the terminal. For any remarks please Contact us
Copyright © 2010 bulkcarrierguide.com All rights reserved.