What is Mechanical Packing?
Mechanical packing is a material that is used to seal different types of liquids. It is also known as compression packing. It can be used to seal many liquids and chemicals, such as water steam, gases, oils, acids and solvents. It is most often used to pack the shaft on motors, pumps and axles. Generally you will want your packing to fit snuggly between the shaft and wall. Packing can be applied two ways: You can wrap the shaft with a length of packing or cut rings and overlap them. Mechanical packing is generally a square and comes in sizes as low as 1/8” and over 1” square.
Mechanical packing is often used in pharmaceutical factories, steel mills, paper mills, and chemical plants. It is also used to seal equipment such as mixers, dryers, and agitators.
Different types of mechanical packing may be used based on the temperature, shaft speed, pressure, and the type of liquid to be sealed.
Mechanical packing may be constructed from several different materials. Graphite Fiber or Carbon yarn are excellent materials with severe temperature requirements. For a very good general purpose packing a synthetic yarn is often used, which may be braided to improve durability. It may also be coated with a lubricant to reduce wear on the machinery. Often it is coated with polytetrafluoroethylene, or PTFE. PTFE is most often known by the brand name Teflon. It is a non-stick coating that, when used as a lubricant, helps to reduce friction and wear and tear on machinery. Sometimes a synthetic yarn is used and treated with graphite, which is an electrical conductor and has lubricating properties. This type of mechanical packing is good for use in sealing steam, oil, and mild acids or alkalis.
Often a PTFE/Graphite or “GFO” combination is required. Blaylock Gasket stocks this material along with many other options for your packing requirements.
Another synthetic fiber known as Meta aramid is often used in the construction of mechanical packing. Meta aramid yarn is braided and lubricated with mineral oil. This type is beneficial because it is quick and easy to install. It provides for very low leakage. However, it should not be used with concentrated acids, alkali metals, oxygen, or caustic materials.
Novoloid fibers are also used for mechanical packing. Novoloid fibers are useful because they are flame-resistant and will not melt. When used in mechanical packing, each strand is coated with PTFE for thorough lubrication. This type of mechanical packing is often used in chemical plants and paper mills.
Pure PTFE packing is also available manufactured with FDA approved virgin PTFE for pharmaceutical and food applications where cleanliness is paramount.
Metallic mechanical packing may be lubricated and treated with graphite for use with gas, ammonia, oil, and steam.
JAMPAK is a putty-like form of mechanical packing. It is very easy to use and install, and can be molded into the desired shape. It reduces friction on machinery, reduces heat, and won't leak.
Natural yarn made from ramie, a plant source, is also used for mechanical packing. It is treated with paraffin and mineral oil to increase its lubricant properties. It does not rot or mildew, which lends to its popular use in the marine industry.
Blaylock Gasket and Packing is a great source for mechanical packing information and ordering.
Click here to Contact us today or call us at 800.259.8770