Svea 123
Encyclopedia
Naphtha
Naphtha normally refers to a number of different flammable liquid mixtures of hydrocarbons, i.e., a component of natural gas condensate or a distillation product from petroleum, coal tar or peat boiling in a certain range and containing certain hydrocarbons. It is a broad term covering among the...
, commonly referred to as “white gas
White gas
White gas is a common name for two flammable substances. In its most common modern usage, it is used as a generic name for camp stove and lantern fuel, usually naphtha....
” or “Coleman fuel
Coleman fuel
Coleman fuel is a petroleum naphtha product marketed by The Coleman Company. Historically called white gas , it is a liquid petroleum fuel sold in one gallon cans. It is used primarily for fueling lanterns and camp stoves. Originally, it was simply casing-head gas or drip gas which has similar...
”) pressurized-burner camping stove that traces its origins to designs first pioneered in the late 19th century.
History
Svea stoves were first made by Nybergs Lödlampfabrik, which also manufactured blowtorchesBlow torch
A blowtorch , blow torch , or blowlamp is a tool for applying lower-intensity and more diffuse flame and heat for various applications, than the oxyacetylene torch. Before aerosol cans and pressurized gas cylinders, fuel was pressurized by a syringe or pump...
as well as other machinery and equipment. Founded by Carl Nyberg, the firm later became one of the largest industries in Sundbyberg, Sweden
Sweden
Sweden , officially the Kingdom of Sweden , is a Nordic country on the Scandinavian Peninsula in Northern Europe. Sweden borders with Norway and Finland and is connected to Denmark by a bridge-tunnel across the Öresund....
. In 1922, the business was taken over by Max Sievert, an early associate of Nyberg’s, and renamed Sieverts Lödlampfabrik (later known as Sievert AB). The Svea 123, introduced in 1955, is considered to be the first compact backpacking
Backpacking (wilderness)
Backpacking combines the activities of hiking and camping for an overnight stay in backcountry wilderness...
white gas stove and one of the most popular camping
Camping
Camping is an outdoor recreational activity. The participants leave urban areas, their home region, or civilization and enjoy nature while spending one or several nights outdoors, usually at a campsite. Camping may involve the use of a tent, caravan, motorhome, cabin, a primitive structure, or no...
stoves ever made. Its distinctive “roaring” sound has been likened to that of a jet engine at takeoff. In 1969, the Svea brand was acquired by Optimus, another Swedish manufacturer of portable stoves, which continued production of the Svea 123 for another four decades, and is still in production. Because of its simple design and reputation for dependable performance, even under extreme conditions, the Svea 123 enjoys a devoted following.
The popularity of portable camping stoves such as the Svea coincided with the increase during the 1950s and 1960s in the awareness of the environmental impact of backpacking, particularly in heavily-traveled areas, and the rise of the Leave No Trace
Leave No Trace
Leave No Trace is both a set of principles, and an organization that promotes those principles. The principles are designed to assist outdoor enthusiasts with their decisions about how to reduce their impacts when they hike, camp, picnic, snowshoe, run, bike, hunt, paddle, ride horses, fish, ski or...
ethic in the 1970s and 1980s. At the same time, scarcity of fuel in over-used camping areas as well as regulatory requirements (open-fire bans) also contributed to the need for a substitute for open campfires
Campfire
A campfire is a fire lit at a campsite, to serve the following functions: light, warmth, a beacon, a bug and/or apex predator deterrent, to cook, and for a psychological sense of security. In established campgrounds they are usually in a fire ring for safety. Campfires are a popular feature of...
for "wilderness" area cooking. Eventually stoves that were lighter in weight than the Svea, as well as those of other designs that were capable of burning a wider variety of fuels (useful when camping in other parts of the world where white gas is difficult to find) knocked it from its perch as one of the most popular backpacking stoves after nearly 50 years of production. However, the rugged and durable Svea 123—often described by long-time users as "bomb-proof" -- still remains popular and continues in wide use.
Construction
Made of solid brassBrass
Brass is an alloy of copper and zinc; the proportions of zinc and copper can be varied to create a range of brasses with varying properties.In comparison, bronze is principally an alloy of copper and tin...
, the Svea 123 weighs about 500 grams (19 ounces), measures 100 mm x 130 mm (3.9” x 5.1”) and will burn for over an hour on full tank (about 4 ounces) of fuel. Later models (designated the “Svea 123R” and also sold as the Optimus “Climber”) were made with a built-in cleaning needle to keep the burner jet from clogging by pushing soot
Soot
Soot is a general term that refers to impure carbon particles resulting from the incomplete combustion of a hydrocarbon. It is more properly restricted to the product of the gas-phase combustion process but is commonly extended to include the residual pyrolyzed fuel particles such as cenospheres,...
or other impurities
Impurity
Impurities are substances inside a confined amount of liquid, gas, or solid, which differ from the chemical composition of the material or compound.Impurities are either naturally occurring or added during synthesis of a chemical or commercial product...
outward; early Sievert models without the self-cleaning needle came with a small wire pricker that is used to clean the burner jet manually by pushing the soot inwards. These older models are distinguishable by their downwardly-angled spindle and control valve, to which the adjusting key is attached. The spindle on a Svea 123R with the self-cleaning needle is at a right angle to the stem. Other differences between older and newer models include the vaporizer on older models, which is smooth, while newer models of both the Svea 123 and the 123R are finned and have a stronger joint configuration at the base. The pressure-relief valve
Safety valve
A safety valve is a valve mechanism for the automatic release of a substance from a boiler, pressure vessel, or other system when the pressure or temperature exceeds preset limits....
in the filler cap has also been redesigned several times to improve both reliability as well as re-seating of the valve after it has opened. A brass windscreen attaches directly to the stove, and has built-in pot supports that fold inward for storage. The aluminum lid comes with a detachable handle and can also be used as a small cook-pot.
Stove Lighting and Operation
To light the stove, the fuel tank must first be pre-heated and pressurized by lighting a small amount of fuel poured into the primer pan or spirit cup (a small well) on top of the tank at the base of the vaporizerVaporizer
A vaporizer or vapouriser is a device used to extract for inhalation the active ingredients of plant material, commonly cannabis, tobacco, or other herbs or blends....
(the vertical stem connecting the fuel tank to the burner). Alternatively, the primer pan can be filled directly from the fuel tank by opening the control valve
Control valves
Control valves are valves used to control conditions such as flow, pressure, temperature, and liquid level by fully or partially opening or closing in response to signals received from controllers that compare a "setpoint" to a "process variable" whose value is provided by sensors that monitor...
and warming the fuel tank by holding it in one’s hands. This will increase the pressure in the fuel tank and force a small amount of fuel to trickle out of the burner jet and into the primer pan. The control valve must then be closed before lighting the priming fuel. The tank can also be pressurized by an optional pump that may be attached to the filler cap, but this is generally not necessary except in extreme cold. Fuel from the tank is fed by a cotton
Cotton
Cotton is a soft, fluffy staple fiber that grows in a boll, or protective capsule, around the seeds of cotton plants of the genus Gossypium. The fiber is almost pure cellulose. The botanical purpose of cotton fiber is to aid in seed dispersal....
wick inside the tank to the base of the vaporizer. The heat and pressure created by the priming flame vaporizes
Vaporization
Vaporization of an element or compound is a phase transition from the liquid or solid phase to gas phase. There are three types of vaporization: evaporation, boiling and sublimation....
the fuel inside the vaporizer. When the priming flame is nearly burnt out, the control valve is opened by turning the adjusting key. This allows the vaporized fuel to flow under pressure through the burner jet (a small opening at the base of the burner), where it mixes with oxygen
Oxygen
Oxygen is the element with atomic number 8 and represented by the symbol O. Its name derives from the Greek roots ὀξύς and -γενής , because at the time of naming, it was mistakenly thought that all acids required oxygen in their composition...
and burns with a blue flame. Adjusting the flow of the vaporized fuel that is forced through the burner jet controls the flame size and heat output. The control valve (a spindle) is threaded in the vaporizer's housing, and as it is opened (by turning the adjusting key) it opens like a faucet
Tap (valve)
A tap is a valve controlling release of liquids or gas. In the British Isles and most of the Commonwealth, the word is used for any everyday type of valve, particularly the fittings that control water supply to bathtubs and sinks. In the U.S., the term "tap" is more often used for beer taps,...
and the vaporized fuel flows through the burner jet. Closing the spindle closes the fuel supply. A small plate on the top of the burner (a flame spreader) spreads the flame outwards. The heat generated in the burner and vaporizer maintains the internal pressure in the fuel tank.
Burner Design and Flame Efficiency
Like most gasoline stoves, the Svea 123 uses an inverted bell-shaped burner topped with a flame spreader (sometimes called a “target burner” or “plate burner” design). As the vaporized fuel exits the jet, it shoots upward and strikes the bottom of the flame spreader, where it mixes with air that is drawn into the burner housing by convection. The air/fuel mixture flows around the bottom of the flame spreader where it burns with a blue flame. In this type of burner design, flame efficiency depends on how fast the vaporized fuel strikes the flame spreader and on how well the air and vaporized fuel mixes beneath the flame spreader (i.e., the amount of turbulence in the air/fuel mixing zone). As a result, this design works best at high fuel output levels; efficient combustion is indicated by a blue flame. As the fuel output is decreased (i.e., when the control valve is turned down) the velocity with which the fuel exits the jet is also decreased, and fuel mixing (i.e., the amount of turbulence in the air/fuel mixing zone) is likewise decreased. At very low fuel output levels, the fuel will no longer exit with sufficient velocity to fully strike the flame spreader and combustion will consequently be very inefficient, usually indicated by a yellow flame.Internal Cleaning Needle
The cleaning needle on the Svea 123R model has two small toothed cogsGear
A gear is a rotating machine part having cut teeth, or cogs, which mesh with another toothed part in order to transmit torque. Two or more gears working in tandem are called a transmission and can produce a mechanical advantage through a gear ratio and thus may be considered a simple machine....
that face each other, which cleans the burner jet from both the inside and outside when using the stove. The cleaning needle moves upward and downward when the spindle is turned; when the spindle is fully opened, the needle clears the burner jet’s opening. As the spindle is closed, the needle retracts into the burner housing. In this way, any soot that may clog the burner jet is expelled.
Reliability
Because the Svea 123 is made of brass and has only one moving part – the control valve (the later Svea 123R model has an additional moving part, the internal self-cleaning needle) – the Svea has a well-established record of reliability and can withstand years of heavy use with only minimal maintenance. Some users have reported operational problems with the self-cleaning needle on the 123R, such as that the stove may not simmer as well as the earlier Sievert models, but reports from years of field use of the Svea on the Appalachian TrailAppalachian Trail
The Appalachian National Scenic Trail, generally known as the Appalachian Trail or simply the AT, is a marked hiking trail in the eastern United States extending between Springer Mountain in Georgia and Mount Katahdin in Maine. It is approximately long...
indicate that it has the lowest record of clogging among stoves used on the trail.
Some common but unrecommended practices can adversely affect the Svea’s performance and reliability. For example, when using a wind screen or shield other than the built-in wind screen (such as the flexible aluminum foil windscreens used with stoves made by Mountain Safety Research
Mountain Safety Research
Mountain Safety Research, or MSR, is an American corporation located in Seattle, Washington, and owned by Cascade Designs. It was founded in 1969 by Larry Penberthy because he was not pleased with the safety and reliability of outdoor equipment....
), care should taken not to wrap the windscreen too tightly around the stove because this may cause the stove to overheat and the fuel tank to over-pressurize. This in turn will cause the pressure-relief valve
Safety valve
A safety valve is a valve mechanism for the automatic release of a substance from a boiler, pressure vessel, or other system when the pressure or temperature exceeds preset limits....
in the filler cap to open and the over-pressurized gas vapor to escape, which may catch fire and result in a dangerous "flareup" or large fireball. In addition, while the Svea is capable of burning unleaded automobile gasoline
Gasoline
Gasoline , or petrol , is a toxic, translucent, petroleum-derived liquid that is primarily used as a fuel in internal combustion engines. It consists mostly of organic compounds obtained by the fractional distillation of petroleum, enhanced with a variety of additives. Some gasolines also contain...
, only naphtha
Naphtha
Naphtha normally refers to a number of different flammable liquid mixtures of hydrocarbons, i.e., a component of natural gas condensate or a distillation product from petroleum, coal tar or peat boiling in a certain range and containing certain hydrocarbons. It is a broad term covering among the...
or "Coleman fuel
Coleman fuel
Coleman fuel is a petroleum naphtha product marketed by The Coleman Company. Historically called white gas , it is a liquid petroleum fuel sold in one gallon cans. It is used primarily for fueling lanterns and camp stoves. Originally, it was simply casing-head gas or drip gas which has similar...
" is recommended: Coleman fuel contains rust inhibitors and is specially refined for use in camping stoves, while automotive fuel contains additives
Gasoline additive
Gasoline additives increase gasoline's octane rating or act as corrosion inhibitors or lubricants, thus allowing the use of higher compression ratios for greater efficiency and power, however some carry heavy environmental risks...
that vaporize when burned and leave gumlike deposits behind that causes clogging. The stove should also not be allowed to run dry because doing so will burn or char the cotton wick inside the fuel tank, which will inhibit the wick’s ability to draw fuel to the vaporizing tube.
Similar Designs and Copies
The Svea 123 shares a number of design features with several other small portable stovePortable stove
A portable stove is a cooking stove specially designed to be portable and lightweight, as for camping or picnicking, or for use in remote locations where an easily transportable means of cooking or heating is needed...
s.
In the 1930s, Sieverts Lödlampfabrik (maker of the original Svea 123) produced the Campus No. 3 stove. Much like the later-produced Svea, it was a self-pressurizing stove with an integrated windscreen and an aluminum lid that doubled as a cook-pot, but was slightly narrower and taller (80 mm x 150 mm) than the Svea. Because of its small size, the Campus No. 3 was advertised as a "boon to Hikers, Cyclists, and Travellers generally." Also in the 1930s, Optimus introduced the No. 6 stove, which was nearly identical to the Svea 123 in size, weight, capacity, operation and design. Optimus dropped the No. 6 in the 1940s and did not produce a similar model until its acquisition of the Svea line in 1969.
The Juwel 33 and 34 (made by Gustav Barthel of Dresden
Dresden
Dresden is the capital city of the Free State of Saxony in Germany. It is situated in a valley on the River Elbe, near the Czech border. The Dresden conurbation is part of the Saxon Triangle metropolitan area....
which, like Sieverts, was a maker of blowtorches and stoves) is a World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
-era German
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
military
Military
A military is an organization authorized by its greater society to use lethal force, usually including use of weapons, in defending its country by combating actual or perceived threats. The military may have additional functions of use to its greater society, such as advancing a political agenda e.g...
field stove of similar size, design and operation to the Svea. The Arara 37, another German-made stove, is similar, as is the Czech
Czechoslovakia
Czechoslovakia or Czecho-Slovakia was a sovereign state in Central Europe which existed from October 1918, when it declared its independence from the Austro-Hungarian Empire, until 1992...
-made Meva Type 2140 and the Russian
Soviet Union
The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....
-made Примус Туристский ПТ-2 "Огонёк" (Primus Tourist PT-2 "Little Flame").
The Swedish-made Primus 71 and the similar Optimus 80 have a larger fuel tank and are slightly taller and heavier than the Svea. (After Optimus acquired the rights to the Primus name for liquid-fueled stoves in 1962, the Primus 71 and Optimus 80 were identical, except for the name and markings.) However, instead of the integrated windscreen on the Svea, the Primus 71 and Optimus 80 stoves fit inside a sheet-metal case for transport that when opened serves as the stove’s windscreen and pot support. The type of fuel used and the method of operation of the Primus 71 is the same as the Svea. The Primus 70 is similar, but with a cylindrical aluminum container instead of a sheet-metal box. The Radius 42, another Swedish-made stove, dates from the 1920s and is slightly smaller than the Primus 71, but is otherwise the same general design.
Taiwan
Taiwan
Taiwan , also known, especially in the past, as Formosa , is the largest island of the same-named island group of East Asia in the western Pacific Ocean and located off the southeastern coast of mainland China. The island forms over 99% of the current territory of the Republic of China following...
ese-made knock-offs
Knock Off
Knock Off is a 1998 Hong Kong action thriller film directed by Hong Kong filmmaker Tsui Hark, and starring Jean-Claude Van Damme, Lela Rochon, Michael Wong and Rob Schneider.-Plot:...
of the Svea 123 include the Fire-Lite and Trav-ler 77, and the Pak-Cook 235 marketed in the United States under the Stansport and Texsport names.