Steel Scrap

Some coal is subject to spontaneous heating, markedly so if the coal comes from a methane rich seam.  However, there are sufficiently adequate supplies of coal throughout the world that consumers are generally able to avoid purchasing such grades. Nevertheless, shipowners/managers contemplating the coal trade should ensure they know which coals are suspect. In any case almost all coal cargoes give off inflammable gas and so ventilation of the holds is important although natural ventilation is enough. By its very nature metal scrap can include heavy or jagged pieces which loaded carelessly can cause damage to the vessel’s frames. Some scrap is in fact steel turnings (the residue from drilling and turning steel).  Such material is drenched in cutting oil which is generally of vegetable origin.  It does, therefore, decompose and in doing so generates so much heat that spontaneous combustion can result;  indeed, steel can burn in such circumstances. However well drained, motor blocks particularly will still drip some oil during the voyage which is very difficult to remove from the vessel’s holds. Sulphur can damage vessel’s steelwork unless it is coated with lime wash before loading commences. Fishmeal is liable to spontaneous combustion.  The total quantity of bulk cargo is usually established by shore weighing.  The Master should double check the figure by means of a draft survey. The loading of non-bulk cargoes is a much more complex, labour intensive and slower operation.  The range of cargoes is much wider and so are the problems which can be met.  They cannot be just poured into the vessel’s holds like bulk cargo, they have to be carefully stowed and, if necessary, lashed and secured. The quantity of non-bulk cargoes is usually established by shore tally but the accuracy of such tallies is often poor and in some ports the tally is virtually non-existent. The Master should arrange for the ship to spot-check the tally to ensure its accuracy.