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# Angle of Repose & Flow Moisture Point on Board

## Test Procedure for “Angle of Repose” on Board:-

In the absence of a tilting box apparatus, an alternative procedure for determining the approximate angle of repose is given in subsection 2.2 of appendix 2 of IMSBC Code

Definition: – According to this method the angle of repose is the angle between the cone slope and the horizontal measured at half height.

Principle of test: – To determine the angle of repose, a quantity of the material to be tested is poured very carefully out of a flask onto a sheet of rough-textured paper, in such a way that a symmetrical cone is formed.

Equipment: – The necessary equipment to carry out this test is as follows:

– a horizontal table free from vibrations;

– a sheet of rough-textured paper onto which the material should be poured;

– a protractor; and

Procedure: – Put the sheet of paper on the table. Split 10l of the material to be tested into three sub-samples and test each in the following way:

Pour two thirds of the sub-sample (i.e., 2 l) onto the sheet, producing a starting cone. The remainder of this sub-sample is then poured very carefully from a height of a few millimetres on top of the cone. Care should be taken that the cone will be built up symmetrically. This may be achieved by revolving the flask slowly close around the top of the cone when pouring.

When measuring, care should be taken that the protractor does not touch the cone; otherwise this may result in sliding of the material and spoil the test.

The angle has to be measured at four places around the cone, about 90 degrees apart.

This test should be repeated on the other two sub-samples.

Calculations:- The angle of repose is taken as the mean of the 12 measurements and is reported to half a degree.

This figure can be converted to the tilting box value as follows:

at = as + 3o

Where,   at = angle of repose according to the tilting box text

as = angle of repose according to the survey test

## Test Procedure for “Flow Moisture Point” (FMP) on Board:-

Definition:- The Flow Moisture Point (FMP), or flow point, is a moisture content (reported in gross water content by weight) determined in two of the three TML test methods stated in Appendix 2 of the International Maritime Solid Bulk Cargoes Code (IMSBC Code).

The Flow Table Test and Penetration Test use the FMP to calculate the Transportable Moisture Limit (TML) of a Group A or liquefiable solid bulk cargo. Once past the FMP a sample is said to have reached its flow state.

Flow Table Test (FTT):- During the Flow Table Test procedure described in Appendix 2 of the International Maritime Solid Bulk Cargoes Code (IMSBC Code), the FMP is calculated as the average gross water content by weight of the two samples on the flow table, one which shows plastic deformation (above FMP) and one which does not show plastic deformation (below FMP). These two samples must have a maximum difference of 0.5% gross water content by weight to be valid.

Equation:- The following equation is derived from the equations given in Appendix 2 of the International Maritime Solid Bulk Cargoes Code (IMSBC Code) which are used to calculate the FMP during the Flow Table Test:

Where:

m1 = mass of wet sample just above the Flow Moisture Point (FMP),

m2 = mass of dry sample just above the Flow Moisture Point (FMP),

m3 = mass of wet sample just below the Flow Moisture Point (FMP) and

m4 = mass of dry sample just below the Flow Moisture Point (FMP).

Penetration Test (PT):- During the Penetration Test procedure described in Appendix 2 of the International Maritime Solid Bulk Cargoes Code (IMSBC Code), the FMP is calculated as the average gross water content by weight of the two samples in the Penetration Test mould, one which shows penetration by the relevant penetration bit greater than 50 mm (above FMP) and one which does not show penetration by the relevant penetration bit greater than 50 mm (below FMP). These two samples must have a maximum difference of 0.5% gross water content by weight to be valid.

Equation:-

The same equation that is used to determine the FMP during the Flow Table Test is used during the Penetration Test.