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Sievert AB on LP gas

 

Gaseous paraffins is the correct description what we call LP gas. LP gas consists of the hydrocarbons propane and butane, or a mixture of the two. These gases are extracted from crude oil. LP gas or LPG stands for liquefied petroleum gas. At normal temperatures, LP gas is gaseous but is a liquid when under pressure. Propane must be distributed in steel cylinders that can withstand high pressure. Butane can be distributed in lighter gas cartridges.

 
 
LP gas and safety
 
Leaking LP gas is a fire hazard.
LP gas is heavier than air.
LP gas uses air during combustion.
 

There are primarily two things to think about to prevent accidents with LP gas. 1. Avoid leakages. 2. Ensure good ventilation. Leaking LP gas can ignite and cause a fire, or in the worst case, an explosion. The cylinder valve should always be closed when the cylinder is not in use. The cylinder should be stored upright and, if possible, at ground level since LP gas is heavier than air and can therefore accumulate in cellars, manholes etc. Good ventilation is important when working indoors as the flame consumes air. Lack of oxygen causes incomplete combustion, which produces carbon monoxide instead of carbon dioxide. Carbon monoxide is a treacherous and deadly gas.

 
 
LP gas and efficiency
 
Permits very high power outputs.
Energy content is high.
Fuel is easy to store and transport.
 

A large amount of fuel only occupies a small space and is therefore easy to store and transport. LP gas forms a combustible mixture with air when the proportion of gas is between 2 and 10 percent. When the gas changes from a liquid to a gaseous form, the volume increases by 250 times. In other words, the energy content is high. LP gas can be stored in its container almost indefinitely without the gas breaking down.

 
 
LP gas and the environment
 
LP gas is non-toxic and does not contain hazardous additives.

It does not contaminate air or water.

 

LP gas does not produce any hazardous combustion gases, just carbon dioxide and water vapor. The gas does not contaminate water, it does not produce soot, it is not corrosive and it does not cause corrosion to iron or other metals. It does not contain lead or heavy metals and is non-toxic. In other words, LP gas is an environmentally friendly fuel. The only additive is a strongly smelling substance that acts as a warning signal for leaking gas. Normally, LP gas has no smell.

 
 
LP gas and handling
 
Work in well-ventilated areas.
Avoid placing the LP gas cylinder near sources of heat.
Ensure that the cylinder is stored upright during transport.
 

You should regularly check valves and connectors for leakage. Remember also that good ventilation is important at areas where the gas is stored or used. Ventilation is also important to ensure effective combustion. Make sure that the cylinder is at ambient temperature when you begin working. If you are going to use the fuel at temperatures below 32°F, use propane instead as butane does not gasify at low temperatures.

 
 
LP gas and fire
 
Always extinguish LP gas fires with powder, never water.
Move LP gas cylinders to a safe place if there is a fire in the vicinity.
If possible, close the valve on the cylinder.
 

Steel cylinders are fitted with a safety valve that opens if the pressure increases too much. This can occur if there is a fire close to the cylinder. The valve stops the cylinder exploding. To guarantee the function of the safety valve, it is important that the LP gas cylinder is stored in a standing position. In addition, a closed valve stops unchecked gas flow if a hose should become damaged.

 
 
LP gas and equipment
 
Never allow an untrained person to use the equipment.
Only use special LP gas parts.
Be extra careful with valves and connectors.
 

Never use other valves, burners or hoses than those designed for use with LP gas. Sievert LP gas hose conforms to the EN 559 standard. The hose consists of an internal rubber layer that is LP gas-proof, armouring an external rubber layer that can withstand air and aging. All equipment shown in this product catalogue is manufactured of materials that withstand LP gas and is designed so that the risk for leakage is minimal.

 
 
LP gas and checks
 
Ensure that you have the correct equipment for the job.
Make sure that you have tightened all valves and connectors.
Regularly inspect the equipment and check that the system is sealed.
 

Read the instructions for use and follow the safety advice. Use soapy water or a special liquid for detecting leakages on valves and joints to find any leaks. LP gas hoses should be checked very carefully and changed if you see any changes. Bend the hoses and look for cracks in the rubber. Hoses exposed to sunlight with age quicker than those used indoors.

 
 
LP gas and storage
 
LP gas is not affected by long storage periods.
Always disconnect equipment form the container.
Store the cylinder in a well-ventilated area.
 

Avoiding storing LP gas cylinders in areas that are warm. Temperatures below zero Celsius are, however, perfectly safe for storage. Ensure that the ventilation is good. In principle, LP gas can be stored indefinitely in its container without the quality being affected. Remember to remove all connectors before storing the equipment. To empty the system of gas, close the valve on the LP gas cylinder. Then close any valves on the rest of the equipment. In this way, you will avoid LP gas spillage when you open the system again.

 
 

LP gas and technical specifications

 
    Butane Propane
  Chemical formula C4H10 C3H8
  Density at 59°F Heavier than air Heavier than air
  as gas 2.40 kg/m3 1.85 kg/m3
  as liquid 0.58 kg/l 0.51 kg/l
  Boiling point at atmospheric pressure 28°F -44°F
  Gas pressure at -4°F 0 22 psi
  Gas pressure at 32°F 0 58 psi
  Gas pressure at +68°F 19 psi 109 psi
  Energy content 49.5 MJ/kg - 12.6 kWh/kg 50.4 MJ/kg - 12.8 kWh/kg
  Amount of air required for combustion 12.0 m3/kg 12.2 m3/kg
  Maximum flame temperature with air 3500°F 3500°F
  Combustion mixtures, volume-% gas in air 1.5 - 8.5 % 2.1 - 9.5%
 
 
LP gas output from a cylinder
 

When LP gas turns from a liquid to a gas, heat is required which is taken from the liquid itself, from the container and from the surrounding air. LP gas and the bottle become cooler which reduces the pressure in the container. For larger burners, and especially during continuous use, a sufficient container size is necessary so that the burner can work at a constant power. When using larger burners or burners with high gas consumption, ensure the cylinder size is large enough to deliver the required gas, without significant temperature drop. Table below shows an example of the maximum quantity of gas possible to use during on hour for burners requiring 29 psi pressure. Conditions for this example are the following: gas – propane, cylinder size 24 lb, continous gas use during one hour, temperature of air and cylinder.

 
  Temperature 68°F 32°F
  Full cylinder 24 lb propane 8.4 lb 3.5 lb
  Half cylinder 12 lb propane 4.2 lb 1.9 lb
 
For large gas burners you need to have big gas cylinders with enough gas or several cylinders linked together.
 
 
Temperature of the gas flame
 

Theoretically, LP gas has a maximum flame temperature of 3500°F. In practice, this temperature is not reached when heating an object. The temperature achieved depends on the size of the object, how much heat is dispersed, the ability of the burner to transfer heat, the size of the burner and how long the object is heated. Therefore, the choice of burner depends on the job to be carried out.

 
 

Melting points of soldering metals

 
  Tin solder 375 - 535°F
  Aluminium soft solder 715°F
  Aluminium hard solder 1080°F
  Silver solder 1130°F
  Phosphor copper solder 1330°F
  Bronze solder 1580°F
 
 

Melting points of metals

 
  Lead 620°F
  Zinc 785°F
  Aluminium 1220°F
  Silver 1760°F
  Gold 1950°F
  Copper 1980°F
 
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Sievert Industries, Inc. - 5255 Zenith Parkway - Loves Park - IL, 61111 - USA - Phone: +1 815 639 1319 - Fax: +1 815 639 1320