Over the coming months we are going to dedicate a certain portion of the news posts to the industries and the end use of our products and the many varied applications they are used for. Today we focus on the Factory Ships of the world and as stainless steel fitting manufacturers, our products are being utilised by a wide variety of different factory ships all over the world. Each of the following vessels and barges are incredibly complex, which require a great deal of durable stasinless steel fittings and adaptors such as BSP 60° Cone & 'O' Ring Adaptors. But here at Custom Fittings, we pride ourselves on being able to produce and distribute various products that the many different ships in this post can utilise and benefit from.
According to the Food and Agriculture Organisation of the United Nations, global total production of fish, crustaceans, molluscs and other aquatic animals was 158 million tonnes in 2012. China was the top-ranking fishing country in terms of quantity, but Indonesia, the USA, India and Peru closely followed. A total of 19 countries caught more than one million tonnes each in 2012, which accounts for over 75 per cent of global catches.
In order to catch and transport this fish, a large ocean-going vessel is required and these are commonly known as factory ships. An increasing number of fishermen are utilising these boats, which are essentially modern incarnations of early whalers due to their large capacity and extensive processing facilities. But how did factory ships come to be? What types of vessel are there and what does the future have in store?
Factory ship background
Essentially, factory ships are a contemporary version of a whaler. These specialised vessels, powered by either stream or diesel, were used to catch whales with a harpoon gun that was mounted to the ship’s bow. Although successful for several centuries, whale catchers had to bring their haul to a separate station or ship anchored in a sheltered bay or inlet. But with the development of the slipway at a ship’s stern, they were soon able to transfer whales to floating factories in the open sea.
Before long, these two vessels became the factory ship we know today. In the past whales were processed on-board and the carcass was discarded. However, as efficiency and capabilities improved, it was possible to convert the entire whale into useable products. Even so, this had its drawbacks and disadvantages, as ruthless productivity contributed greatly to the animals’ rapid decline. As a result, a number of species were threatened with extinction and certain regulations were brought in. Factory ships are now used less and less for whaling, but their use in fishing continues to grow.
As mentioned previously, countries like China and the United States of America still use factory ships extensively, whereas nations such as Russia and Korea have gradually lessened their dependence on these vessels. Currently, Japan has the world’s only whaler factory ship, the 8,145-ton vessel MV Nisshin Maru.
Nevertheless, they can also function as mother ships, which carry small fishing boats out into the ocean and then process their catch.
Types of factory ship
A factory stern trawler is different to other ships of its kind due to the on-board processing facilities. What’s more, it can stay at sea for days or even weeks a time. A trawler works by actively dragging or pulling a fishing net through the water at a specified depth or the bottom of the sea. It can also operate two or more trawl nets simultaneously (double and multi-rig) depending on the ship, ocean and fishing conditions.
A stern trawler hauls its catch up a ramp and can be demersal (weighted bottom trawling) or pelagic (mid-water trawling). Pair trawling, which is similar to double and multi-rig fishing, involves two vessels pulling one extensive net at the same time.
Trawlers can trace their roots back to the 17th century when the British developed the Dogger, which operated in the North Sea. A couple of hundred years later and the “Brigham trawler” or “Mother of Deep-Sea Fisheries” heavily influenced future vessel design. However, their construction was also effected by ever changing fuel sources, from sail and coal-fired steam to diesel engines and turbines.
Although it is still labour intensive, modern trawlers feature motorised winches, mechanised hauling devices, electronic navigation and sonar systems. Freezer trawlers are ships capable of processing fish into fillets within hours of being caught. Fishmeal plants can also process waste products so that everything is used. The largest freezing trawler in the world, the 144-metre-long Annelies Ilena ex Atlantic Dawn, can process 350 tones of fish a day, carry 3,000 tonnes of fuel and store 7,000 tonnes of grade and frozen catch.
Factory bottom longliner
As opposed to nets, bottom longliners catch fish by using hooks strung on lines. The hooks are baited automatically and attached at intervals along the line, which are released very quickly. Thousands of hooks are set and hung from a single line every day in the hope of catching species like tuna, halibut and swordfish.
The setting and retrieval of longline fishing is a continuous daily operation that never truly ends and ships can be out at sea for six weeks at a time. Therefore, these vessels also feature on-board storage and processing facilities. Fish are cut, frozen and packed within hours of being caught.
Seeing as longlines can be set to hang near the surface or along the sea floor, it is a fishing process prone to the incidental catching and killing of seabirds, turtles and sharks. It is also one of the main threats to albatrosses, as longline fishing kills an estimated 100,000 per year. For that reason, it is quite controversial in some areas and measures have been introduced to mitigate incidental mortality.
Seine fishing refers to a net that hangs vertically in the water with weights holding down the bottom edge and floats buoying the top edge. The net is set in a circle around of school of fish and then pursed, closing the bottom and pulling it up. The catch is transferred into a tank filled with brine, which freezes the fish quickly.
Seine fishing dates back to the Stone Age, where woven green flax nets and large canoes were used to catch vital food. Seine nets also appear on Egyptian tomb paintings and in ancient Greek literature.
Again, due to extensive on-board facilities, factory purse seiners can remain out at sea for up to two months. The tanks are unloaded directly to the canneries or on carrier vessels so that fishing can continue.
Future of factory ship
As long as there are still fish in the sea, it is fair to say that factory ships will remain in operation. Even though a few ecological and environmental challenges exist, technological advancements and a greater understanding of our oceans can make factory ships more sustainable and eco-friendly.
In the future, factory ships might be built with more automated machinery on-board, which could make fishing a less labour-intensive activity. But for the time being at least, fishermen can rely on the aforementioned vessels to provide them with a living and put food, possibly even fish, on the table.