Q. What hazard is caused by grain?
Bulk grain because of its semi fluid property is liable to shift during heavy rolling at sea. The grain after shifting sideways does not return to original location and in fact may invite more grain. A shift of grain can cause a vessel to list to a dangerous degree. She may even capsize.
Q. What are 1960 equivalent regulations?
IMO Assembly in 1969 adopted new grain regulations [resolution A.184 (VI)], which became known as the 1969 Equivalent Grain Regulations. These regulations subsequently incorporated into the 1974 SOLAS Convention. IMO resolution A.264 (VIII) revoked earlier Resolution. This resolution caused amendment to chapter VI of SOLAS 60.
Q. How did grain code come in force? To which ship it applies?
Resolution MSC 22 (59) adopted amendments to SOLAS 1974, including chapter VI. Chapter VI was now to be supplemented by Grain Code that took effect on 1st Jan 1994. It applies to all ships – including existing ships and those of less than 500 gross that carry grain in bulk.
Q. What is contained in part A and part B of grain code?
Part A contains special requirements and gives guidance on the stowage of grain and the use of grain fittings. Part B deals with the calculation of heeling moments and general assumptions.
Q. In part A of Ch VI of SOLAS, what is said about bulk cargoes?
Chapter VI of SOLAS deals with “Carriage of Cargoes”. Part A is General. Thus, “The shipper shall provide the Master or his representative with appropriate information on the cargo sufficiently in advance of loading to enable the exercise of precautions which may be necessary for proper stowage and safe carriage of the cargo. Such information shall be confirmed in writing and by appropriate shipping documents prior to loading the cargo on the ship. In case of bulk cargoes, information shall be on the stowage factor of the cargo, the trimming procedures, likelihood of shifting including angle of repose, if applicable and any other relevant special properties.
Q. What is part C of Ch VI of SOLAS?
PART C (SOLAS) is Carriage of Grain. Reg. 9 deals with the requirement for cargo ships carrying grain. It states that in addition to any other applicable requirement of the present regulations, a cargo ship carrying grain shall comply with the requirement of the International grain code and hold a document of authorization as required by the code, thus making the code mandatory. A ship without such a document shall not load grain until the Master satisfies the Administration or the Contracting Government of the port of loading on behalf of the Administration that the ship will comply with the requirements of the International Grain Code in its proposed loaded condition.
Q. What is the effect of settling down of grain?
Due to vibration and movement of the ship at sea the grain settles down (by about 2% of its vol.) resulting in increasing the size of existing voids at the top of the compartment.
Q. What is the relation between the angle of repose, roll amount and angle of hopper? |
Bulk grain has a low angle of repose. Angle of repose has relationship with the amount of roll and the inclination of hopper tanks. If the ship rolls to an angle greater than angle of repose, risk of grain shift exits. A slope of hopper tank more than angle of repose would make a hold self trimming. An angle of more than 30 degrees to horizontal is advised in grain code.
Q. How is grain defined?
The term grain covers wheat, maize (corn), oats, rye, barley, rice, pulses, seeds and processed forms thereof, whose behaviour is similar to that of grain in its natural state.
Q. What is the difference between filled compartment, trimmed and filled compartment, untrimmed?
The term filled compartment, trimmed, refers to any cargo space in which, after loading and trimming as required, the bulk grain is at its highest possible level. This implies that the compartment is of the tween decker ship, which is not of the self trimming type. The manual means of trimming is required.
The term filled compartment, untrimmed, refers to a cargo space which is filled to the maximum extent possible in way of the hatch opening but which has not been trimmed outside the periphery of the hatch opening because of:
- structural arrangements (self trimming arrangements, feeder ducts, etc); or
- the compartments having vertical or sloping grain tight bulkheads limiting the effect of transverse shift of grain.
Q. What is angle of flooding?
The term angle of flooding (θf) means the angle of heel at which openings in the hull, superstructures or deckhouses, which cannot be closed weathertight, immerse. In applying this definition, small openings through which progressive flooding cannot take place need not be considered as open.
Q. What is specially suitable compartment?
The term specially suitable compartment refers to a cargo space which is constructed with at least two vertical or sloping, longitudinal, graintight divisions which are coincident with the hatch side girders or are so positioned as to limit the effect of any transverse shift of grain. If sloping, the divisions shall have an inclination of not less than 30° to the horizontal.
Q. What are grain stability criteria?
The intact stability of the ship carrying grain in bulk shall be shown to meet at least the following criteria after taking into account the assumed shift of grain. The assumed shift of grain is to an extent of 25° (15° for certain areas)
- The angle of heel obtained from a plot of the statical stability curve and heeling arm curve shall not be greater than 12° .The administration will provide a lesser angle than 12° if considered necessary.
- The residual area between the righting arm curve and the heeling arm curve up to an angle of 40° or the angle of flooding or the angle of maximum separation between the two curves whichever is least shall be at least 0.075 m-radian ( not less than 0.075 m-radian)
- The initial GM shall be at least 0.3 m.
Q. In what way the local Administration controls the safety of the vessels loading grain?
Before loading the bulk grain, the master shall if required by authorities, demonstrate the ability of the ships to comply with the stability criteria required by this section. After loading master will ensure the vessel is upright before proceeding to sea.
Q. What recommendations are provided in respect of trimming the grain in any filled compartment trimmed?
Regulation 10 of the code has recommendations in respect of stowage of bulk grain. It says that all necessary and reasonable trimming shall be performed to level all grain surfaces and minimize the effect of grain shifting. In any filled compartment, trimmed, the bulk grain should be trimmed to fill up under deck spaces to maximum possible extent. The filled compartment trimmed implies a non self trimming hold where additional trimming is necessary.
Q. What about a self trimming hold?
In case of self trimming hold, there would be provisions for trimming outside the hatch square. Therefore, in untrimmed filled compartment maximum filling shall be done in the way of hatch opening.
Q. What about partly filled compartment?
Unless account is taken of adverse heeling effect due to grain shift according to the grain code, the surface of partly filled compartment shall be secured so as to prevent a grain shift by over stowing. Alternately, the surface may be secured by strapping or lashing.
Q. What is document of authorization?
Document of authorization is issued by Administration or Recognized Organization to every ship capable of being loaded in accordance with grain code. It shall be accepted as evidence that the ship is capable of complying with relevant regulations.
It is dealt under regulation 3 of the code. The document is accompanied with grain loading manual which enables Master meeting the grain stability criteria and has required information as provided in code.
Q. What if a ship does not have a DOA?
A ship without DOA shall not load grain until the Master demonstrates to the satisfaction of Administration or Contracting Government of port of loading on behalf of Administration that vessel is loaded appropriately for the intended voyage.
Q. What is the provision in respect of carrying of grain, securing and stability requirement for a vessel, not given DOA?
Regulation 9 of code deals with optional stability requirements for ships without DOA carrying partial cargoes of bulk grain. A ship without DOA may be permitted to load bulk grain provided:
- Total grain weight does not exceed 1/3rd deadweight of ship.
- Filled compartments, trimmed shall be fitted with appropriate centre line divisions. (Saucers may be accepted).
- All hatches to filled compartment, trimmed shall be closed and secured.
- All free grain surfaces are leveled, secured by overstowing, strapping / lashing or by securing with wire mesh.
- Throughout the voyage GMo, after correction of free surface shall be 0.3m or that given by the following formula whichever is greater.
L is total combined length of full compartments (m), B the moulded breadth (m), SF the stowage factor (m3/t), Vd the calculated average void depth (m) & the displacement in tonnes.
6. Master must demonstrate to the satisfaction of Administration or Contracting Government of port of loading on behalf of Administration that the ship will comply with the requirements of this section.
Q. What are the contents of Grain Stability Booklet?
Information in printed booklet form shall be provided to enable the Master to ensure that the ship complies with this code when carrying grain in bulk on an international voyage. Information which shall be acceptable to the Administration or to a Contracting Government on behalf of the Administration and shall include:
- ship’s particulars;
- lightship displacement and the vertical distance from the intersection of the moulded base line and midship section to the centre of gravity (KG)
- table of liquid free surface corrections;
- capacities and centres of gravity;
- curve or table of angle of flooding, where less than 400 at all permissible displacements;
- curve or tables of hydrostatic properties suitable for the range of operating drafts; and
- cross curves of stability which are sufficient for the purpose of the requirements in A7 and which include curve at 120 and 400.
It must be noted that all the 15 items required by the Intact Stability Code 2008 must also be included. Additionally, in the grain stability book the information provided shall be approved by the Administration or by a Contracting Government on behalf of the Administration and shall include:
- curves or tables of volumes, vertical centres of volumes, and assumed volumetric healing moments for every compartment filled or partly filled or combination thereof including the effects of temporary fittings;
- tables or curves of maximum permissible heeling moment for varying displacement and varying vertical centres of gravity to allow the master to demonstrate compliance with the relevant requirement;
This requirement shall apply only to ships the keels of which are laid on or after the entry into force of this code.
- details of the scantling of any temporary fittings and where applicable the provisions necessary to meet the relevant requirements;
- loading instructions in the form of notes summarizing the requirements of this code;
- a worked example for the guidance of the Master; and
- typical loading service departure and arrival conditions and where necessary intermediate worst service conditions.
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