A tank truck, gas truck, fuel truck, or tanker truck or tanker, is a motor vehicle designed to carry liquefied loads, dry bulk cargo or gases on roads. The largest such vehicles are similar to railroad tank cars which are designed to carry liquefied loads. Many variants exist due to the wide variety of liquids. Tank trucks tend to be large; some are semi-trailer trucks. They are difficult to drive due to their high center of gravity. Tank trucks are described by their volume capacity. Large trucks have capacities ranging from 5,500 to 11,600 US gallons. In Australia, road trains up to four trailers in length carry loads in excess of 120,000 L. Longer road trains transporting liquids are in use. A tank truck is distinguished by its shape a cylindrical tank upon the vehicle lying horizontally; some less visible distinctions amongst tank trucks have to do with their intended use: compliance with human food regulations, refrigeration capability, acid resistance, pressurization capability, more. The tanks themselves will always contain multiple compartments or baffles to prevent load movement destabilizing the vehicle.
Large tank trucks are used for example to transport gasoline to filling stations. They transport a wide variety of liquid goods such as liquid sugar, milk, juices, gasoline and industrial chemicals. Tank trucks are constructed of various materials depending on; these materials include aluminium, carbon steel, stainless steel, fiberglass reinforced plastic. Some tank trucks are able to carry multiple products at once due to compartmentalization of the tank into 2, 3, 4, 5, 6 or in some rare cases more tank compartments; this allows for an increased number of delivery options. These trucks are used to carry different grades of gasoline to service stations to carry all products needed in one trip. Smaller tank trucks, with a capacity of less than 3,000 US gallons are used to deal with light liquid cargo within a local community. A common example is vacuum truck used to empty several septic tanks and deliver the collected fecal sludge to a treatment site; these tank trucks have a maximum capacity of 3,000 US gallons.
They are equipped with a pumping system to serve their particular need. Another common use is to deliver fuel such as liquified petroleum gas to households and industries; the smallest of these trucks carry about 1,000 US gallons of LPG under pressure. LPG tank trucks carry up to 3499 US gallons of product, on a 2 axle bobtail truck. 3500 US gallons and greater requires a 3 axle truck. Some companies are using lightweight steel to carry more gallons on single-axle trucks. Notably, one U. S. manufacturer has built a 3700 US gallon tank truck. Tank trucks are used to fuel aircraft at airports. Driving Tank Trucks for a Living
DC-10 Air Tanker
The DC-10 Air Tanker is a series of American wide-body jet air tankers, which have been in service as an aerial firefighting unit since 2006. The aircraft, operated by the joint technical venture 10 Tanker Air Carrier, are converted wide body McDonnell Douglas DC-10 passenger jetliners, are used to fight wildfires in rural areas; the turbofan-powered aircraft carry up to 12,000 US gallons of water or fire retardant in an exterior belly-mounted tank, the contents of which can be released in eight seconds. Four air tankers are in operation, all DC-10-30 aircraft, with the call-signs Tanker 910, 911, 912 and 914; the original Tanker 910, a DC-10-10, was retired in 2014. 10 Tanker began researching the development of Next Generation airtankers in 2002. Company personnel were assembled with an extensive history of heavy jet operations and ownership. After two years of research into aerial firefighting requirements and future direction, 10 Tanker selected the DC-10 type for development. A Supplemental Type Certificate from the US Federal Aviation Administration for modifications of DC-10 aircraft to be used for the aerial dispersant of liquids was issued in March 2006.
10 Tanker obtained a 14 CFR Part 137 Operating Certificate for aerial firefighting and Interagency Airtanker Board approval for agency use. The first converted aircraft, registered as N450AX, was delivered as a civil passenger plane to National Airlines in 1975, subsequently flew for Pan Am, American Airlines, Hawaiian Airlines and Omni Air International; the conversion of the original airframe to a fire-fighting aircraft was a joint venture under the name of 10 Tanker Air Carrier between Cargo Conversions of San Carlos and Omni, with conversion work being performed by Victorville Aerospace at the Southern California Logistics Airport in Victorville, California. The air tanker modification can be carried out to either a DC-10-10 or DC-10-30 series and involves the addition of an external tank and associated systems and support structure; the water or retardant is carried in three center-line belly tanks. The tanks have internal baffles to prevent fluid shift while in flight, sit with a 15-inch ground clearance.
All three tanks can be filled on the ground in eight minutes. The retardant is gravity-fed out of the tanks, the entire load can be dumped in eight seconds, although the actual drop rate is computer controlled by the flight crew in order to produce the desired retardant spread over the fire lines; the aircraft is capable of applying a line of retardant 300 feet wide by 1 mile long. The external retardant tanks are designed to be filled from standard 3-inch cam-lock couplings. Utilizing one, two or three hoses, the tanks can be filled as as base loading capabilities permit 15–20 minutes; the tanks are vented to atmosphere by a vent system installed on top of each tank to allow sufficient air into and out of the tanks during retardant drops and filling. Accurate quantity gauges are part of the installation; the number of drops it can make in a day is only limited by the time it takes to reload the aircraft with water/fire retardant and fuel, as well as its need for a proper landing field, which may well be a considerable distance from the fire.
Skeptics have argued. However, despite its size, field experience has proven the plane’s agility above all types of terrain and in all atmospheric conditions deemed suitable for fixed wing operations in a Fire Traffic Area. Unlike most existing and proposed Large Air Tankers, the DC-10 arrives at a Fire Traffic Area weighing less than its certified maximum gross takeoff weight; this is principally due to the reduced fuel load carried on fire missions. As a result: The 10 is dispatched at a takeoff weight 40% lighter than its certified MGTOW; the 10 turns comfortably within the turn radii of smaller aircraft including Single Engine Air Tankers and lead planes. The 10’s improved thrust to weight ratio increases rate of climb, enhances safety margins in a failed engine scenario; the 10 enjoys a wide margin above stall at typical drop speeds and weights with a full retardant load. One drop from the aircraft is equivalent to 12 drops from a Grumman S-2 Tracker; the aircraft was intended to be operated in California, the entire state was serviced from the plane's Victorville base at the Southern California Logistics Airport, but in 2007 Cal Fire began looking into setting up a second operations base at Sacramento McClellan Airport in Northern California.
10 Tanker Air Carrier announced in 2007 that a second aircraft would be converted to tanker usage for the 2008 fire season. The DC-10s operate with a flight crew of a pilot, co-pilot and a flight engineer; the tanker works with a lead plane and can be an effective tool in combating wildfires when working directly with ground resources. 10 Tanker Air Carrier added a second DC-10 flown by Continental Airlines, to its fleet in July 2008, to be used on an on-call basis. On December 19, 2009, the aircraft – designated Tanker 911 – arrived in Melbourne, for the Australian fire season. Leased by the National Aerial Firefighting Centre on behalf of the Victoria state government, the DC-10 became operational in Australia in early January 2010, based at Avalon; the Premier of Victoria at the time, John Brumby, described the leasing of the tanker as being part of a record financing program to make sure the state was as fire-ready as possible. In late 2014, the company added two additional DC-10s which had served with Omni and N
A water tender known as a tanker in some regions, is a specialized firefighting apparatus designed for transporting water from a water source to a fire scene. Water tenders are capable of drafting water from a lake or hydrant; this class of apparatus does not have enough pumping capacity to power large hose lines, though it utilizes a smaller pump to draft from bodies of water. Water tenders are used when there is no working fire hydrant within reach of other fire equipment supplying the fire engine with a rapid connection. Most water tenders are designed to carry loads of 1000 gallons or more. In the US, 1000 gallons is the requirement in the NFPA standards; some may carry up to or upwards of 5000 gallons of water – more with a trailer. Water tenders support engines and/or trucks like aerials during fires and hazardous material incidents; some water tenders carry fire fighting crew much like an engine. These water tenders are able to operate independently; some water tenders combine a fire engine and water tender.
This kind of unit may have seats for up to six firefighters, a water tank of more than 3000 gallons, basic equipment for firefighting and rescue. This configuration may be found, for example, in rural areas, where a fire engine and water tender are supported by a combined fire engine/water tender unit in overlapping fires or accidents. Numerous wildland water tenders have remotely controlled nozzles mounted on the front bumper to allow them to drive alongside a fire or smoldering area and efficiently wet it down without the crew leaving the rig. Light water tenders are sometimes used in wildfires. For example, a small tank of 265 gallons can be carried by a cross-country vehicle to extinguish smoldering stubs on rough terrain. A water tender carries some fire fighting equipment. There are various national standards and recommendations on equipment to be carried on water tenders; some water tenders may carry various kinds of hoses and spray nozzles for use in forest, building, or industrial fires, as well as a portable water tank.
In addition, tools like axes, chemical portable fire extinguishers, a water extinguisher, an SCBA, a first aid kit, a hydrant wrench can be required. Some tenders carry foaming agents, extinguishing powders or gases. Sometimes these materials are carried in larger amounts on specialized, separate units like hose trucks, powder trucks, carbon dioxide extinguishing trucks etc. Specialized Airport Crash Tenders are used at airports to carry larger amounts of water and foaming agents. An Australian Water Tender can range from a standard fire engine, with a larger-than-usual capacity, to a Water Tender equipped with specialty equipment such as fixed monitors and long-throw foam nozzles. Several areas own converted semi-trailer fuel tankers, capable of holding many thousands of litres of petrol, foam or other retardant; these are most used in severe HazMat situations, such as oil refinery fires or fuel tanker accidents, where a large and continuous volume of water is needed. Fire Chief's Vehicle Heavy rescue vehicle Fire apparatus Fireboat Portable water tank
Aerial refueling referred to as air refueling, in-flight refueling, air-to-air refueling, tanking, is the process of transferring aviation fuel from one military aircraft to another during flight. The two main refueling systems are probe-and-drogue, simpler to adapt to existing aircraft, the flying boom, which offers faster fuel transfer, but requires a dedicated boom operator station; the procedure allows the receiving aircraft to remain airborne longer, extending its range or loiter time on station. A series of air refuelings can give range limited only by crew fatigue and engineering factors such as engine oil consumption; because the receiver aircraft can be topped up with extra fuel in the air, air refueling can allow a takeoff with a greater payload which could be weapons, cargo, or personnel: the maximum takeoff weight is maintained by carrying less fuel and topping up once airborne. Alternatively, a shorter take-off roll can be achieved because take-off can be at a lighter weight before refueling once airborne.
Aerial refueling has been considered as a means to reduce fuel consumption on long-distance flights greater than 3,000 nautical miles. Potential fuel savings in the range of 35-40% have been estimated for long haul flights; the aircraft providing the fuel is specially designed for the task, although refueling pods can be fitted to existing aircraft designs if the "probe-and-drogue" system is to be used. The cost of the refueling equipment on both tanker and receiver aircraft and the specialized aircraft handling of the aircraft to be refueled has resulted in the activity only being used in military operations. There is no known regular civilian in-flight refueling activity. Employed shortly before World War II on a limited scale to extend the range of British civilian transatlantic flying boats, after World War II on a large scale to extend the range of strategic bombers, aerial refueling since the Vietnam War has been extensively used in large-scale military operations. For instance, in the Gulf War and the Iraqi invasion of Kuwait and the Iraq War, all coalition air sorties were air-refueled except for a few short-range ground attack sorties in the Kuwait area.
Some of the earliest experiments in aerial refueling took place in the 1920s. The first mid-air refueling, based on the development of Alexander P. de Seversky, between two planes occurred on June 27, 1923, between two Airco DH-4B biplanes of the United States Army Air Service. An endurance record was set by three DH-4Bs on August 27–28, 1923, in which the receiver airplane remained aloft for more than 37 hours using nine mid-air refuelings to transfer 687 US gallons of aviation gasoline and 38 US gallons of engine oil; the same crews demonstrated the utility of the technique on October 25, 1923, when a DH-4 flew from Sumas, Washington, on the Canada–United States border, to Tijuana, landing in San Diego, using mid-air refuelings at Eugene and Sacramento, California. Similar trial demonstrations of mid-air refueling technique took place at the Royal Aircraft Establishment in England and by the Armée de l'Air in France in the same year, but these early experiments were not yet regarded as a practical proposition, were dismissed as stunts.
As the 1920s progressed, greater numbers of aviation enthusiasts vied to set new aerial long-distance records, using inflight air refueling. One such enthusiast, who would revolutionize aerial refueling was Sir Alan Cobham, member of the Royal Flying Corps in World War I, a pioneer of long-distance aviation. During the 1920s, he made long-distance flights to places as far afield as Africa and Australia and he began experimenting with the possibilities of in-flight refueling to extend the range of flight. Cobham was one of the founding directors of Airspeed Limited, an aircraft manufacturing company which went on to produce a specially adapted Airspeed Courier that Cobham used for his early experiments with in-flight refueling; this craft was modified by Airspeed to Cobham's specification, for a non-stop flight from London to India, using in-flight refueling to extend the plane's flight duration. Meanwhile, in 1929, a group of U. S. Army Air Corps fliers, led by Major Carl Spaatz, set an endurance record of over 150 hours with the Question Mark over Los Angeles.
Between June 11 and July 4, 1930, the brothers John, Kenneth and Walter Hunter set a new record of 553 hours 40 minutes over Chicago using two Stinson SM-1 Detroiters as refueler and receiver. Aerial refueling remained a dangerous process until 1935 when brothers Fred and Al Key demonstrated a spill-free refueling nozzle, designed by A. D. Hunter, they exceeded the Hunters' record by nearly 100 hours in a Curtiss Robin monoplane, staying aloft for more than 27 days. The US was concerned about transatlantic flights for faster postal service between Europe and America. In 1931 W. Irving Glover, the second assistant postmaster, wrote an extensive article for Popular Mechanics concerning the challenges and the need for such a regular service. In his article he mentioned the use of Aerial refueling after take off as a possible solution. At Le Bourget Airport near Paris, the Aéro-Club de France and the 34th Aviation Regiment of the French Air Force were able to demonstrate passing fuel between machines at the annual aviation fete at Vincennes in 1928.
The UK's Royal Aircraft Establishment was running mid-air refueling trials, wi
A tanker is a ship designed to transport or store liquids or gases in bulk. Major types of tankship include the oil tanker, the chemical tanker, gas carrier. Tankers carry commodities such as vegetable oils and wine. In the United States Navy and Military Sealift Command, a tanker used to refuel other ships is called an oiler but many other navies use the terms tanker and replenishment tanker. Tankers can range in size of capacity from several hundred tons, which includes vessels for servicing small harbours and coastal settlements, to several hundred thousand tons, for long-range haulage. Besides ocean- or seagoing tankers there are specialized inland-waterway tankers which operate on rivers and canals with an average cargo capacity up to some thousand tons. A wide range of products are carried by tankers, including: Hydrocarbon products such as oil, liquefied petroleum gas, liquefied natural gas Chemicals, such as ammonia and styrene monomer Fresh water Wine Molasses Citrus juice Tankers are a new concept, dating from the years of the 19th century.
Before this, technology had not supported the idea of carrying bulk liquids. The market was not geared towards transporting or selling cargo in bulk, therefore most ships carried a wide range of different products in different holds and traded outside fixed routes. Liquids were loaded in casks—hence the term "tonnage", which refers to the volume of the holds in terms of how many tuns or casks of wine could be carried. Potable water, vital for the survival of the crew, was stowed in casks. Carrying bulk liquids in earlier ships posed several problems: The holds: on timber ships the holds were not sufficiently water, oil or air-tight to prevent a liquid cargo from spoiling or leaking; the development of iron and steel hulls solved this problem. Loading and discharging: Bulk liquids must be pumped - the development of efficient pumps and piping systems was vital to the development of the tanker. Steam engines were developed as prime-movers for early pumping systems. Dedicated cargo handling facilities were now required ashore too - as was a market for receiving a product in that quantity.
Casks could be unloaded using ordinary cranes, the awkward nature of the casks meant that the volume of liquid was always small - therefore keeping the market more stable. Free surface effect: a large body of liquid carried aboard a ship will impact on the ship's stability when the liquid is flowing around the hold or tank in response to the ship's movements; the effect was negligible in casks, but could cause capsizing if the tank extended the width of the ship. Tankers were first used by the oil industry to transfer refined fuel in bulk from refineries to customers; this would be stored in large tanks ashore, subdivided for delivery to individual locations. The use of tankers caught on because other liquids were cheaper to transport in bulk, store in dedicated terminals subdivide; the Guinness brewery used tankers to transport the stout across the Irish Sea. Different products require different handling and transport, with specialised variants such as "chemical tankers", "oil tankers", "LNG carriers" developed to handle dangerous chemicals and oil-derived products, liquefied natural gas respectively.
These broad variants may be further differentiated with respect to ability to carry only a single product or transport mixed cargoes such as several different chemicals or refined petroleum products. Among oil tankers, supertankers are designed for transporting oil around the Horn of Africa from the Middle East; the supertanker Seawise Giant, scrapped in 2010, was 458 meters in length and 69 meters wide. Supertankers are one of the three preferred methods for transporting large quantities of oil, along with pipeline transport and rail. Despite being regulated, tankers have been involved in environmental disasters resulting from oil spills. Amoco Cadiz, Erika, Exxon Valdez and Torrey Canyon were examples of coastal accidents. Many modern tankers are designed for a specific route. Draft is limited by the depth of water in loading and unloading harbors. Cargoes with high vapor pressure at ambient temperatures may require pressurized tanks or vapor recovery systems. Tank heaters may be required to maintain heavy crude oil, residual fuel, wax, or molasses in a fluid state for offloading.
Tankers used for liquid fuels are classified according to their capacity. In 1954, Shell Oil developed the average freight rate assessment system, which classifies tankers of different sizes. To make it an independent instrument, Shell consulted the London Tanker Brokers’ Panel. At first, they divided the groups as General Purpose for tankers under 25,000 tons deadweight; the ships became larger during the 1970s, the list was extended, where the tons are long tons: 10,000–24,999 DWT: Small tanker 25,000–34,999 DWT: Intermediate tanker 35,000–44,999 DWT: Medium Range 1 45,000–54,999 DWT: Medium Range 2 55,000–79,999 DWT: Large Range 1 80,000–159,999 DWT: Large Range 2 160,000–319,999 DWT: Very Large Crude Carrier 320,000–549,999 DWT: Ultra Large Crude Carrier Very Large Crude Carrier size rangeAt nearly 380 vessels in the size range 279,000 t DWT to 320,000 t DWT, these are by far the most popular size range among the larger
A tank car is a type of railroad car or rolling stock designed to transport liquid and gaseous commodities. The following major events occurred in the years noted: 1865: Flatcars with banded wooden planks or decking mounted on top are employed for the first time to transport crude oil from the fields of Pennsylvania during the Pennsylvanian oil rush. 1869: Wrought iron tanks, with an approximate capacity of 3,500 US gal per car, replace wooden tanks. 1888: Tank-car manufacturers sell units directly to the oil companies, with capacities ranging from 6,000 to 10,000 US gal. 1903: Tank-car companies develop construction safety standards. More than 10,000 tank cars are in operation. 1915: A classification system is developed by the tank-car industry to ensure the correct match of car type to product being shipped. Some 50,000 tank cars are in use. 1930: 140,000 tank cars transport some 103 commodities. 1940s: Virtually every tank car is engaged in oil transport in support of the war effort. 1945–1950: Welding replaces riveting in car construction for the major manufacturers, including American Car & Foundry and General American.
1950: Pipelines and tank trucks begin to compete for liquid transport business. 1963: The Union Tank Car Company introduces the "Whale Belly" tank car. Many variants exist due to the wide variety of gases transported. Tank cars can be pressurized or non-pressurized, insulated or non-insulated, designed for single or multiple commodities. Non-pressurized cars may have fittings on the bottom; some of the top fittings are covered by a protective housing. Pressurized cars have a pressure plate, with all fittings, a cylindrical protective housing at the top. Loading and unloading are done through the protective housing. Tank cars are specialized pieces of equipment; as an example, the interior of the car may be lined with a material, such as glass, or other specialized coatings to isolate the tank contents from the tank shell. Care is taken to ensure; as a result of this specialization, tank cars have been "one-way" cars. Other cars, like boxcars, can be reloaded with other goods for the return trip. Combinations of the two types were attempted, such as boxcars with fluid tanks slung beneath the floors.
While the car could carry a load in both directions, the limited tank size made this unsuccessful. A large percentage of tank cars are owned by companies serviced by railroads instead of the railroads themselves; this can be verified by examining the reporting marks on the cars. These marks invariably end in X. Within the rail industry, tank cars are grouped by their type and not by the cargo carried. Food-service tank cars may be lined with glass, or plastic. Tank cars carrying dangerous goods are made of different types of steel, depending on the intended cargo and operating pressure, they may be lined with rubber or coated with specialized coatings for tank protection or product purity purpose. The tank heads are stronger to prevent ruptures during accidents; the whale-belly type is giving way to higher-capacity, yet AAR Plate "C", cars. All tank cars undergo periodic inspection for corrosion. Pressure relief valves are inspected at every loading. Pressurized cars are pressure-tested to ensure the integrity of the tank.
All tank cars operating throughout North America today feature AAR TypeE double shelf couplers that are designed to prevent disengaging in event of an accident or derailment. This reduces the chance of couplers puncturing adjacent tank cars. However, if cars are prevented from disengaging in a derailment, the torsional forces of a derailing car can be transferred to other cars, resulting in the derailment of the adjacent cars. Insulated cars are used. For example, the Linde tank car depicted below carries liquefied argon. Cars designed for multiple commodities are constructed of two or more tanks; each compartment must have separate fittings. The lower capacity and added complexity of multicompartment cars means that they make up a small percentage of the tank car inventory. Outside of North America, tank cars are known as tank wagons or tanker wagons. In the United Kingdom tank wagons were traditionally four-wheel vehicles; some long-wheelbase four-wheelers are still in use but bogie vehicles are now used as well.
British tank wagons The DOT-111 tank car, which are designed to carry liquids, such as denatured fuel ethanol, is built to a US standard. The design has been criticized on safety grounds; the train in the Lac-Mégantic derailment of 2013 was made up of 72 of these cars. DOT-112 tank cars are used in North America to carry pressurized gases. DOT-114 tank cars are used in North America to carry pressurized gases. A milk car is a specialized type of tank car designed to carry raw milk between farms and processing plants. Milk is now chilled, before loading, transported in a glass-lined tank car; such tank cars are placarded as "Food service use only". Tank cars of this type are designed to carry cryogenic liquid Hydrogen. North American cars are classified as DOT113, AAR204W, AAR204XT A pickle car was a specialized type of tank car designed to carry pickles; this car consisted of several wooden or metal vats and was roofed. Pickles which are preserved in salt brine were loaded through hatches in the roof.
A tank containe
A chemical tanker is a type of tanker ship designed to transport chemicals in bulk. As defined in MARPOL Annex II, chemical tanker means a ship constructed or adapted for carrying in bulk any liquid product listed in chapter 17 of the International Bulk Chemical Code; as well as industrial chemicals and clean petroleum products, such ships often carry other types of sensitive cargo which require a high standard of tank cleaning, such as palm oil, vegetable oils, caustic soda, methanol. Oceangoing chemical tankers range from 5,000 tonnes deadweight to 35,000 DWT in size, smaller than the average size of other tanker types due to the specialized nature of their cargo and the size restrictions of the port terminals where they call to load and discharge. Chemical tankers have a series of separate cargo tanks which are either coated with specialized coatings such as phenolic epoxy or zinc paint, or made from stainless steel; the coating or cargo tank material determines what types of cargo a particular tank can carry: stainless steel tanks are required for aggressive acid cargoes such as sulfuric and phosphoric acid, while'easier' cargoes — such as vegetable oil — can be carried in epoxy coated tanks.
The coating or tank material influences how tanks can be cleaned. Ships with stainless steel tanks can carry a wider range of cargoes and can clean more between one cargo and another, which justifies the additional cost of their construction. In general, ships carrying chemicals in bulk are classed into three types: Tankers intended to transport products with serious environmental and safety hazards requiring maximum preventive measures to prevent any leakage of cargo. Tankers intended to transport products with appreciably severe environmental and safety hazards requiring significant preventive measures to preclude an escape of such cargo. Tankers intended to transport products with sufficiently severe environmental and safety hazards to require a moderate degree of containment to increase survival capability in a damaged condition. Most chemical tankers are IMO 2 and 3 rated, since the volume of IMO 1 cargoes is limited. Chemical tankers have a system for tank heating in order to maintain the viscosity of certain cargoes by passing pressurized steam through stainless steel'heating coils' in the cargo tanks, transferring heat into the cargo, which circulates in the tank by convection.
All modern chemical tankers feature double-hull construction and most have one hydraulically driven, submerged cargo pump for each tank with independent piping, which means that each tank can load a separate cargo without any mixing. Many oceangoing chemical tankers may carry numerous different grades of cargo on the same voyage loading and discharging these "parcels" at different ports or terminals; this means that the scheduling, stowage planning and operation of such ships requires a high level of coordination and specialist knowledge, both at sea and on shore. Tank cleaning after discharging cargo is a important aspect of chemical tanker operations, because cargo residue can adversely affect the purity of the next cargo loaded. Before tanks are cleaned, they must be properly ventilated and checked to be free of explosive gases. Chemical tankers have transverse stiffeners on deck rather than inside the cargo tanks, in order to make the tank walls smooth and thus easier to clean using permanently fitted tank cleaning machines.
Cargo tanks, either empty or filled, are protected against explosion by inert gas blankets. Nitrogen is the inert gas used, supplied either from portable gas bottles or a Nitrogen generator. Most new chemical tankers are built by shipbuilders in Japan, Korea or China, with other builders in Turkey, Italy and Poland. Japanese shipbuilders now account for the large majority of stainless steel chemical tankers built, as welding stainless steel to the accuracy required for cargo tank construction is a difficult skill to acquire. Notable major chemical tanker operators include Stolt-Nielsen, Navig8 and Mitsui O. S. K. Lines. Charterers, the end users of the ships, include oil majors, industrial consumers, commodity traders and specialist chemical companies. Minaminippon Shipbuilding Shin Kurushima Dockyard Damen Shipyards Group Ship transport List of tankers IBC Code