Penetration test for solid bulk cargoes
The IMSBC Code appendix 2 paragraph 1.2 vibration procedure that judges a solid bulk cargo above its flow moisture point when penetration exceeds 50 mm.
The penetration test is the second of the six IMSBC Code appendix 2 procedures for determining the transportable moisture limit of a solid bulk cargo. The Code states it is generally suitable for mineral concentrates, similar materials, and coals up to a top size of 25 mm, which makes it one of only two routes open to a coal cargo alongside the modified Proctor/Fagerberg procedure at appendix 2 paragraph 1.5.
The method vibrates the prepared sample vertically at 2 g rms plus or minus 10 percent for six minutes. When the penetration depth of a bit resting on the sample surface exceeds 50 mm, the sample is judged to be above the flow moisture point. The procedure runs as a preliminary test followed by a main test, and the preliminary test may be omitted where the approximate flow moisture point is already known. Because the flow moisture point is derived as in appendix 2 paragraph 1.1.4.3, the 90 percent transportable moisture limit rule of paragraph 1.1.4.4.3 carries over.
The full article will cover the apparatus, the sample preparation and moisture increments, the interpretation of a borderline penetration reading, and how the result is presented on a certificate issued by a competent authority independent of the shipper.