GRAIN STABILITY CALCULATIONS , RIGHTING LEVER, GRAIN HEELING MOMENT, CURVES OF STATISTICAL STABILITY, DRAFT CALCULATIONS,
The International Code for the Safe Carriage of Grain in Bulk (International Grain Code), adopted by resolution MSC.23 (59), has been mandatory under SOLAS chapter VI since 1 January 1994. 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. The International Grain Code applies to ships regardless of size, including those of less than 500 gross tonnage, engaged in the carriage of grain in bulk and to which part C of SOLAS chapter VI applies. The purpose of the Code is to provide an international standard for the safe carriage of grain in bulk.
The International Grain Code requires a document of authorization to be issued for every ship loaded in accordance with the Code. The document of authorization serves as evidence that the ship is capable of complying with the requirements of the Code and it must be accompanied or incorporated into the grain loading manual which contains information that enables the master to meet the stability requirements of the Code. A copy of the document of compliance together with the grain loading stability data and associated plans shall be carried on board in order that the master, if so required, shall produce them for the inspection of the Contracting Government of the country of the port of loading.
NOTIFICATION OF LOADING, OR SAILING AFTER PARTIAL DISCHARGE, OF BULK GRAIN
Marine Order 33 Cargo and Cargo Handling - Grain
Chapter VI of the SOLAS 1974 Convention, as amended, and Australian legislation (Marine Order 33 [Cargo and Cargo Handling – Grain] require that ships intending to carry grain cargoes in bulk from Australian ports may be requested to demonstrate compliance with the International Grain Code.
This form provides the means by which the Australian Maritime Safety Authority will determine whether the Master will be required to demonstrate compliance with the stability requirements of the Code to an attending AMSA Surveyor prior to loading his ship. AMSA226 provides the means by which the Master can demonstrate compliance with the stability requirements of the Code.
SOLAS 1974 requires the cargo shipper to provide the Master or his representative with appropriate information on the cargo.
Beyond this it is the Master’s responsibility to ensure the proper stowage of the cargo in accordance with Marine Order 33.
INSTRUCTIONS TO MASTERS
This form is required to be submitted to AMSA at least 72 hours prior to the vessels proposed commencement of loading. If an inspection is deemed to be necessary prior to the commencement of loading AMSA will notify the Master/Agent accordingly.
In the case of intending to sail after partial discharge, a completed form is required to be submitted to AMSA at least 24 hours prior to the anticipated time of sailing.
The Master or Agent is required to submit the form to the nearest AMSA office of the port at which grain is to be loaded or partially discharged (see over).
A separate form is required to be submitted for each successive port the master may lodge all the notifications together for each port to the relevant office prior to the first port of call or alternatively, individually to each appropriate office.
Strict adherence to the layout of this form is not necessary as long as the information required by it can be provided by alternate means.
A new form is required to be submitted to AMSA if there is any significant change in the loading plan.
AMSA applies the following provisions when assessing compliance with the Code:
1. The Code requires all compartments in which grain is stowed to be either “filled” (trimmed or untrimmed) or “partly filled” (trimmed only). AMSA does not accept “partly filled” compartments untrimmed, even if data for these is approved by the flag State Administration, as they are not provided for in the Code.
2. AMSA cannot accept a compartment as being “filled” if the average ullage at the coaming exceeds the minimum required to accommodate the structure of hatch covers or 100mm, whichever is greater.
3. Untrimmed moments may only be used for filled compartments with the ends untrimmed.
4. (NB: Some Australian grain loading terminals lack the facility to adequately trim the ends of filled compartments and Masters must check the facilities at their load ports if they consider they need to trim the ends of any compartments in order to meet the required stability criteria).
5. In partly filled compartments AMSA accepts grain surfaces in which the height between the highest peaks and the lowest troughs in the compartment is not more than 1.0m as being “level” within the meaning of the Code and therefore trimmed to an acceptable level.
6. It is the responsibility of the Master to ensure that the cargo is trimmed as required by the Code - AMSA will not determine the method by which this is achieved.
CALCULATION OF STABILITY FOR SHIPS CARRYING BULK GRAIN
G – A
INSTRUCTIONS TO MASTER FOR LOADING GRAIN IN AUSTRALIAN PORTS
Chapter VI of SOLAS 74, as amended, requires the shipper to provide the master or his representative with appropriate information on the cargo. Beyond this, it is the master’s responsibility to take precautions for the proper stowage of the cargo.
Chapter VI further requires a cargo ship carrying grain to comply with the International Grain Code (“Code”) and to have a document of authorization as required by that Code. Grain cargoes are generally loaded within the limitations of the vessel’s Document of Authorization and the approved Grain Loading Manual. A ship without such documents is required to satisfy AMSA and its flag State that the ship complies with the Code in its proposed loading condition.
Precautions for the proper stowage of the cargo include:
• obtaining from the local agent or other authoritative source at the loading port, the quantity of, and accurate stowage factor for, the grain to be loaded and trimming methods available;
• cargo planning should allow for the possibility that the actual stowage factor could vary substantially from that expected;
• calculations of stability and shear force / bending moments for all conditions of loading and all stages of the voyage while carrying grain, from commencement of loading to arrival at the last port of discharge. These calculations should demonstrate compliance with the Code and all relevant statutory and classification society requirements. Please note that this form requires the stability to be calculated for the worst condition that can occur during the voyage;
• ensuring that all cargo space bilge wells are clean, suctions clear and pumping arrangements operating satisfactorily.
• ensuring bilge well covers have sufficient holes for drainage and, after pre-loading inspection by shore-based personnel, are covered with burlap or similar material to allow drainage while preventing loss of grain into the wells;
• ensuring that any necessary portable fittings and/or hinged partitions are securely erected and made suitably grain-tight, and
• ensuring that all light fittings, and other electrical circuits not required for the safe operation of the ship, within the cargo space are isolated from the power source.
AMSA requires the following interpretations to be followed in relation to compliance with the Code:
• the Code requires all compartments in which grain is stowed to be either “filled” (trimmed or untrimmed) or “partly filled” (trimmed only). AMSA does not accept “partly filled” compartments untrimmed, even if data for these is approved by the flag State Administration, as they are not provided for in the Code;
• AMSA cannot accept a compartment as being “filled” if the average ullage at the coaming exceeds the minimum required to accommodate the structure of hatch covers or 100mm, whichever is greater;
• untrimmed moments may only be used for filled compartments;
• calculations for any filled compartment are to be based on the full (ie. 100% cubic) capacity and corresponding maximum VCG of the compartment irrespective of whether the cargo is to be trimmed or untrimmed;
• AMSA accepts grain surfaces in which the height between the highest peaks and the lowest troughs in the compartment is not more than 1.0m as being “level” within the meaning of the Code and therefore trimmed to an acceptable standard;
• the surface of grain cargo in each partly filled compartment is to be evenly distributed and not used to remove a list;
• it is the responsibility of the master to ensure that the cargo is trimmed as required by the Code - AMSA will not determine the method by which this is achieved, and
• any list (heel) is to be corrected before the vessel sails.
AMSA has no objection to the engagement of a consultant or supercargo to assist ship’s personnel in achieving compliance with the above requirements. However, if inspection by an AMSA surveyor reveals non-compliance with these requirements, it may be necessary for AMSA to insist on rectification, the possible engagement of a consultant or the implementation of the control provisions of STCW’95.
Simpson’s rules are used to calculate the area, volume and geometric centre of the space enclosed by a straight line and a curve
Simpson's 1st rule
Also known as the 1-4-1 rule (after the multipliers used )
Simpson's 2nd rule
Also known as the 1-3-3-1 rule, Simpson's second rule is a simplified version of Simpson's 3/8 rule.
Simpson's 3rd rule
Also known as the 5 - 8 -1 rule
ONLY IF YOU HAVE THE GUTS TO ALLOW THE CANDIDATE TO QUESTION YOUR OWN COMPETENCE AS AN EXAMINER-- ONLY THEN -- HE WILL ACCEPT REJECTION.
OTHERWISE HE WILL THINK-- A BLACK MONKEY WHO DOES NOT KNOW A SHIT ABOUT ENGINEERING FAILED ME.
capt ajit vadakayil
CAPT AJIT VADAKAYIL
30 YEARS IN COMMAND