2.1 History of the Industry
Ship repairing was originally a service provided by ship builders for vessels they had built and in many cases the necessary facilities formed an adjunct to the building yard. The ship repairing industry is now quite separate to shipbuilding. Some of the most important considerations for trade are the yard’s location (whether near to major trade routes), the capacity of the yard (determined often by the type and size of dry dock), availability of constant and experienced labour and the ability to compete for work in a competitive and often international market.
Competition for repair work is intense in particular from repair slips and floating docks on the Continent, and therefore repair yards on the South and East coasts of England are more directly affected by competition from the Continent than elsewhere. The cost of diverting vessels to repair yards is now a significant factor in determining whether owners will use British repair yards and, if so, which.
Broadly, the years 1850-1914 saw the first generation of dry docks built. These were constructed mainly of stone block walls stepped back from the flagged stone floor of the dock to ground level. Lock type gates were fitted and operated by wire hawsers and winches. Dry docks of this period were commonly in the region of 105-140 metres long by 12-18 metres wide by 4.75-6 metres depth of water over cill. Each yard usually had two docks each accommodating vessels up to 7110 tonnes deadweight. These dry docks which were built to take ships of narrow beam and deep keel, are of unsuitable dimensions for modern requirements and are now mainly used for docking smaller vessels.
In the years 1920-1930 it became evident that the pre-first World War docks were too small to accommodate the ships being built and dry dock facilities needed to be extended. Second generation docks were constructed during this period either by extension of the existing docks or by new construction. The former design of stepped walls continued but considerable improvement was effected in gate design and hydraulic operation was introduced. Dry docks of this period were in the region of 167 metres long by 21 metres wide by 7-8 metres deep over cill. These accommodated vessels of up to 50,800 tonnes deadweight and comprise the bulk of repairing dry docks in use today in the UK.
In the 1940-1960 period the construction of the welded steel ship was perfected, and vessels progressively increased in size. The existing docks were not of sufficient capacity to take these larger ships, so a third generation of docks was constructed, but this time with straight steel sheet piled and reinforced concrete walls and ‘drop flap’ gates or floating caissons. These docks were essentially rectangular in cross section to accommodate the changed shape of ships, which by now had a very broad beam and no perceptible keel. Improved pumping machinery and ancillary equipment was installed, in some cases including hydraulically adjustable keel blocks and bilge keep supports. The docks of this period are in the region of 215 metres long by 29-36.5 metres wide by 8-9 metres deep over cill.
Most rationalisation that has taken place up to the late 1970s has been incidental to shipbuilding regrouping and has occurred where a shipbuilding yard with a ship repairing section has been formed into a shiprepairing or composite group.
The major ship building yards were nationalised under the Aircraft & Shipbuilding Industries Act 1977, and a large number of ship repair yards were also taken over by British Shipbuilders. A number of smaller yards continued to operate under private ownership, in particular Bristol Channel Ship Repairs Ltd which in 1973 operated 4 yards in South Wales.
Since 1977 the industry has continued to contract, with large redundancy programmes and dock closures. It could be argued however that although the total amount of repair business has fallen, that which remains has been sufficient to sustain the surviving yards.
In 1983 a decision was taken to sell British Shipbuilders repair facilities, and during the course of the 1983/1984 financial year a number of ship repair yards were closed and or disposed of, the largest being the Tyne Shiprepair Group.
After privatisation a number of repair yards returned to modest profitability in 1984/1985, although the industry continues to experience difficult trading conditions.
By 1986 the Royal Naval Dock Yards at Rosyth and Devonport had been privatised and these repair facilities entered into direct competition with the other yards.
2.3 State of the Industry
The ship repairing industry was historically tightly connected to the shipbuilding industry. However, it has had to become more independent, particularly since the decline of shipbuilding.
The larger operators can be in direct competition with shipbuilding yards for larger repair contracts for naval and merchant shipping. There is competition from foreign yards for this business. Repairs afloat are now more common, taking a team of engineers to a vessel for repair rather than bringing that vessel to a dry dock. There has also been a growth in the number of floating docks; in-water surveys and cleaning services have developed. All of the above have reduced demand and profitability within the shiprepair industry. In addition the requirement for an annual hull survey (an “MOT” for ships) has been modified to longer intervals reducing the frequency of out-of-water inspections.
The smaller operators are not affected by world trade; the business is wholly domestic. The work tends to be predominantly maintenance and refits.
See the relevant Practice Note for comments on the state of industry as at the appropriate valuation date.
2.4 Process of Shiprepairing
Shiprepairing involves 2 major activities:-
- work above the water line or inside the vessel, and
- work below the water line including inspection of the hull.
Work above the water line or inside vessels can be carried out with the ship moored at a quay. Power services from the quay are available at most yards.
Most work below the water line, including scraping and painting the hull, can only be undertaken in a dry dock. The ship must be manoeuvred into the dry dock at a state of tide or level of water in an impounded basin sufficient to allow the keel to clear the cill of the dock. The dock gates/caisson are then closed and the trapped water is either pumped out of the dock or allowed to flow out through the sluice gates as the tide ebbs. The ship will settle onto the keel blocks and is strutted as necessary off the sides of the docks to ensure stability. After completion of the work the dock is flooded and the vessel is moved out.
There is no rigid pattern of work in the shiprepairing industry as this is dependent upon the repairs required. Yards are equipped with buildings and plant which provide most of the repair services but some specialist work is sub-contracted. In some cases repair services are provided at sea, and as Dry Docking Regulations are relaxed this is becoming an increasingly common practice.