Plywood is a commodity which is transported in large quantities in seaborne trades throughout the world. It is also a commodity which is highly susceptible to damage and is often insufficiently prepared for shipment.
The manufacture of plywood has been described as the ‘unrolling of logs of wood’. Very long thin sheets are shaved from the log which, after being cut to size, are glued together to form various thicknesses of plys of wood. Thicknesses vary from around 4 mm to 25 mm and the sheets vary in size, the most popular being 96”x 48”. Moisture content of this manufactured product has been found to be about nine percent.
The method of transporting plywood is to stack the sheets into bundles of about fifty sheets or more, depending on the thickness of the plywood, which are secured together with metal strapping bands. Access for ease of handling by fork-lift trucks is usually achieved by attaching wooden bearers to the individual flat metal securing bands across the width of the base of each bundle. It is not unusual for plywood to be transported in a completely unprotected condition. In some trades the plywood is partly packed, and, on rare occasions, it is completely packed and well protected.
Very often when packing is used, it is deficient, failing adequately to protect those areas which are vulnerable to handling damages, such as on the corners of the bundles. One of the most common forms of packing is an arrangement where the stack of plywood is placed upon a wooden frame after the plywood has been enfolded in a plastic sheet. The sides, ends and top are then covered with plywood sheets and then strapped up with flat metal strapping bands. If done properly and with care, this packing can adequately protect the plywood from normal handling and stowage problems. Often, this packing is applied without sufficient care. Any deficiency or tear in the plastic sheeting can allow moisture penetration into the bundle of plywood. This moisture will seep between the plywood sheets causing staining.
The strapping bands are sometimes of inadequate strength and the method of joining them is often unsatisfactory. This results in a lack of rigidity of the bundle causing the plywood sheets to become misaligned during handling in the worst cases the bundle becomes loose with the damage to the edges of the plywood being considerable. If the plywood, end and top packing is too short, corner damage can occur.
It can be seen from the above that it is of the utmost importance that bundles of plywood should be examined by the ship’s staff before loading (break bulk), paying particular attention to the packing of the plywood, if any. Deficiencies in packing should be noted and suitable remarks inserted on the Mate’s receipts and bills of lading. Careful attention should be paid to stowage, to prevent corner damage both during the stowage and in the securing of the stow. The stow should be properly secured to prevent movement of the bundles of plywood during the voyage. Proper ventilation should be carried out during the voyage to minimise any possible staining from condensation. If possible, stowage should be away from the hatch square to prevent the possibility of moisture dripping down on the plywood externally, if the plywood is totally unprotected.
