Heat Gun Usage

Shrink wrapping has been widely used since about 1965 with great progress made in the improvement of shrink film resins and heat applicators.  Heat shrink film is a low density polyethylene (LDPE) film made from a fractional low melt resin and other additives, and when subjected to heat begins a bi-axially shrinking process as the heat is removed.  There are a variety of heat shrink films available in widths, lengths, thickness and colors, for a variety of applications.  All shrink films are not alike, and will perform differently depending on the resins and manufacturing process used.  A satisfactory shrink wrap cover is dependent upon a quality shrink film and materials, a proven procedure when using the shrink wrap heat gun, and the ability of the person doing the work.

The following heat applicator (heat gun) products are primarily used for heavy duty shrink wrapping.  They are used for industrial applications where the heat shrink film is usually 4 mil (.004") or thicker.  These heavy duty industrial heat guns are not suitable for thin gauge shrink film of less than 4 mil.  There are other types of industrial heat guns and heat applicators available.  A heat gun, and components, is a commercial tool used to perform certain functions and when used in accordance with manufacturers' instructions, industry standards and practices, and common sense, can be operated safely.  A propane heat gun should always be kept out of the reach of small children and other persons without the ability to use such a device.  Always use with long cuff leather safety gloves and eye protection.  Never point a propane heat gun at anyone, including yourself.  Always make sure that the heat gun, any extension, hose, regulator and LP (Liquid Propane) gas tank is maintained in good working order.  When the shrink fast heat gun is not in use or will be left unattended, always shut off the LP tank valve.  Some heat gun shields and nozzles get extremely hot during use and care must be taken not to touch these hot surfaces, or to let the hot surface come into contact with a combustible product surface.  Always use the heat gun in a well ventilated area and away from any fumes or objects that could be ignited.  A heat gun during operation will produce carbon dioxide, carbon monoxide and water vapor.  A person using a heat gun should have ready access to a fire extinguisher in case of a fire.

The specifications data shown herein has been obtained from the manufacturer publication regarding the marketing of their product.  The accuracy of this data or verification thereof is not warranted and is shown only for general comparison purposes.  Be sure to read the product information, safety considerations and important information about liquid propane (LP) gas. 

How to Use Heat Gun for Shrink Wrap

Before using an industrial heat gun kit, the purchaser and/or user should read the manufacturer instructions. Under no circumstances should an industrial heat gun product be altered or modified, or operated in any component is known or suspected to be defective, or that could cause a change in its operation.

The hose used to connect the industrial heat gun to the regulator is a special high pressure rated type with swagged end connectors and left hand threads. Do not attempt to repair a worn or damaged hose or use any other type of hose end connector. Replacement of a complete hose assembly is recommended rather that attempting repairs.

The regulator performs the function of reducing the higher LP tank pressure down to a lower hose and heat gun working pressure. Each model heat gun is designed to achieve maximum efficient operation at a certain pressure. While some regulators are adjustable, operating the heat gun at too low or too high a pressure can damage the combustion chamber, or cause a malfunction. Regulators that may become defective should be returned to a factory authorized repair facility. Do not attempt to repair or modify a LP gas regulator. Do not use any other type of gas control regulator. The regulator is attached to the LP tank at the tank shut-off valve with a P.O.L. connector. When making this connection be sure that the threads and mating surfaces are clean and have no nicks or scratches.

The LP tank is a pressure vessel (container) manufactured in accordance with the rules and regulations of the American Society of Mechanical Engineers (ASME) and the American Gas Association (AGA). There are two types of LP tanks, liquid withdrawal (used as a fuel tank for fork lifts and other internal combustion engines) and vapor withdrawal (used with outdoor cooking grills, heating appliances and heat guns). Do not attempt to use or modify a liquid withdrawal LP tank for use with a heat gun. LP tanks come in various sizes, the most common being 20, 40 60 and 100 pounds. Tanks should be maintained in good condition and not allowed to become rusty or the shut-off valve damaged. Do not use a known or suspected damaged LP tank. When the LP tank has been used for some time, the temperature may drop to about zero degrees F, causing icing on the outside. This icing will appear on nearly empty or smaller size tanks sooner than large ones. This icing is a warning not to use the heat gun when the gauge shows less than 22 PSI. Wait until the ice is gone before continuing use, or switch to another tank. A 20 pound LP tank may start to ice after 60 minutes of continuous use.

Heat Gun Safety Considerations

An industrial heat gun is intended for professional use only, and only by persons who have been trained in its operation and experienced in its use. Good safety practices are important when using a heat gun. Never point a operating heat gun towards yourself, another person, a LP gas tank, the hose, or any combustible material. When using a heat gun there is a danger zone of up to four feet ahead of the nozzle, and in some cases up to eight feet. Always wear safety gloves and eye protection when using a heat gun and avoid wearing nylon or other highly flammable clothing. Always use the heat gun in accordance with manufacturer instructions. Keep a heat gun out of reach of small children and other persons without the ability to use such a device. During operation, an industrial heat gun produces a flame of up to 3500 degrees F and like other liquid propane (LP) gas fired appliances consumes air and produces carbon dioxide, carbon monoxide and water vapor. Always provide adequate ventilation when using heat guns and avoid prolonged breathing of the gas fumes.

 

Safe Levels & Effects of Carbon Monoxide Exposure

Level Effect
9 ppm (.0009%)

Maximum allowable concentration for short term exposure in a living area.

50 ppm (.0050%)

Maximum allowable concentration for continuous exposure in any eight hour period.

200 ppm (.02%)

Slight headache, tiredness, dizziness after 2-3 hours.

400 ppm (.04%)

Headache within 1-2 hours and life threatening after 3 hours.

800 ppm (.08%)

Dizziness, nausea and convulsions within 4-5 minutes, and death within 1 hour.

Limited Warranty

The sole obligation of Pro-Tect Plastics and Supply, Inc., or the manufacturer of these heat gun products, shall be to replace or repair, at its option, any heat gun component (with the exception of the ignitor, ignitor wire/connector, or hose) for a period of one year from the date of purchase, at no charge to the original purchase of the heat gun, providing that any such replacement or repair of a component is found to be faulty in manufacture or assembly and not caused by improper purchaser use or neglect, and shall not be liable for any injury, ,loss, or damage, either direct or consequential, arising out of the use of or the inability to use the product. Before using a heat gun product (including the heat gun, extensions, hose, regulator, LP tank and the LP gas) the purchaser and/or user assumes the risk and liability whatever in connection therewith. This limited warranty offered in conjunction with the manufacturer and sale of a heat gun product is exclusive and in lieu of any other warranties, express, implied, or statutory, including without limitation and direct or implied warrant of merchant-ability of fitness for a particular use.

Important Information About Liquid Propane (LP) Gas

Propane gas is a refined petroleum byproduct of natural gas and crude oil. Propane is odorless and colorless as refined and looks like water. Water boils at +212 degrees F at sea level, and propane boils at -44 degrees F. Boiling of water and propane produce a steam vapor. The water steam is often visible, where the propane steam is a colorless flammable gas. The higher the temperature above the boiling point for both water and propane, the greater the pressure. Sulfur is added to the propane as a warning agent giving the gas a rotten egg smell. Propane has three safety hazards associated with its use: it's flammable, it's under pressure, and it can freeze. A propane heat gun will produce carbon dioxide, carbon monoxide and water vapor.

Propane gas is compressed 270 times to a liquid state for storage. One gallon of liquid propane will make 36.5 cubic feet of gas vapor at sea level (It will make more vapor at higher altitudes). Each cubic foot contains 2,500 BTU's (British Thermal Units) and uses about 19 parts of air to 1 part of gas to burn properly. A gallon of liquid propane weighs 4.24 pounds and contains about 91,600 BTU's per pound. It weighs about one-half as much as water as liquid and is about one and a half times as heavy as air.

Combustibility of propane gas depends on a gas to air ratio between 3.15 and 9.6 percent to ignite and burns at about 3,500 degrees F. An important property of propane as its expansion as it is warmed. Propane gets about one and one-half percent larger for every 10 degrees it is warmed. Heat the gas 100 and fuel will increase 15 percent more. The difference in using propane gas in Miami with the temperature at 90 degrees and in Minneapolis at -10 degrees is significant.

The Basic Facts About LP Gas Are:

Pounds Per Gallon 4.24
Cubic Foot of Gas per Gallon Liquid

36.3

Cubic Foot of Gas Per Pound

8.5

Vapor pressure at 9 degrees

F. - 24 P.S.I.

Vapor pressure at 35 degrees

F. - 85 P.S.I.

Vapor pressure at 70 degrees

F. - 109 P.S.I.

Vapor pressure at 100 degrees

F. - 176 P.S.I.

BTU Output Per Gallon

91,600

BTU Output Per Pound

21,670

 

A 20 pound LP cylinder will contain 4.8 gallons of liquid propane and provide 433,400 BTUs of heat. An empty 20 pound capacity steel LP tank will weight 19 pounds. Add to this 4.8 gallons of propane at 4.24 pounds per gallon for fuel weight of 20.4 pounds and the full 20 pound LP tank should weigh 39.4 pounds.

How long will your LP tank last during shrinking? Divide the output of the heat gun into the BTU capacity of your tank. For example, if you use a heat gun with a 142,000 BTU output with a 20 pound LP tank, it will last about 3 hours. If it takes 15 minutes of heat gun use to shrink film, then you can do 12 items per 20 pound tank.

When the LP tank has been used for some time the tank temperature can drop to a about 0 degrees F, causing icing on the outside. This icing will appear on nearly empty or smaller tanks sooner than large ones. This icing is a warning not to use the heat gun when the gauge shows less than 22 psi. Wait until the icing is gone before using the LP tank or switch to another LP tank. A 20 pound LP tank may start to ice after about 60 minutes of continuous use.