By definition filtration means removing one substance or material from another generally by a mechanical or physical operation. The process of air filtration involves separation of solids from gases by interposing a barrier through which only the clean gas can pass. This barrier is known as a filter medium. A filter medium must satisfy the requirements of efficient flow rate, satisfactory mechanical and chemical resistance and quality of filtrate or cake. Dust particles pollute the air and therefore adequate filtration is necessary prior to their discharge. Environmental regulations have become more demanding and it is our moral responsibility to save and protect our environment. It is obligatory on the part of industry to ensure that air being emitted is clean, without dust or harmful chemicals.

‘Baghouse’ is a generic name for Air Pollution Control Equipment. Fabric filters commonly known as bag-houses comprise an array of long narrow bags that are suspended in large enclosures. Several bags typically in the diameter of 120mm to 400mm and length of 2mtr to 10mtr are arranged vertically in this enclosure. These bags are used to filter dust particles from dusty gasses. Dust laden gas enters the baghouse and pass through the fabric bags that act as filters. The gas passes upwards/downwards through the bag and leaves behind a cake of dust outside/inside the bag. Common types of Bag-houses are Mechanical Shaker, Reverse Air, Pulse Jet and the new Hybrid bag-houses.

Filter Bags are woven or non-woven in nature. Urja is in the field of manufacturing only woven fabrics from Fiberglass. The count of yarn and weave pattern can be altered to determine the pore size for filtration. Fiberglass is strong, durable, chemically resistant and non-hygroscopic in nature. Long tubular bags stitched from Fiberglass Fabrics are used for hot flue gas filtration. Special finishes or coatings are imparted on theses fabrics to ensure adequate filtration. A commonly used mixture of graphite, silicone and PTFE has been used since many years. Urja offers specific fabrics for demanding applications and chemical attacks.

PTFE (Poly–tetra-fluoro-ethylene) is a synthetic fluoropolymer ‘accidentally’ invented by Roy Plunkett that finds numerous applications. It is well known by the DuPont brand name Teflon. PTFE is a material of remarkable properties; non-stick, friction-free, self-lubricating, non-wetting, non-flammable, non-brittle, non-toxic, resistant to atmospheric conditions, resistant to fungus growth and resistant to all chemicals (except molten alkali metals and fluorine at elevated temperatures and pressures). Its electrical properties are equally outstanding. All properties are maintained over a wide working temperature range of -200oC to +350oC.

Fiber-Glass too is a material of remarkable properties. Fabrics made from continuous filament yarn exhibit superior properties in terms of high tensile strength, low elongation, high temperature resistance, electric and sound insulation etc.

Welding blankets are used to protect human beings, materials and equipments from welding splatters/sparks produced during the process of welding. Blankets are also used to protect surroundings from heat during gas cutting and gas welding.

Welding blankets are made from Glass fabrics, High Silica fabrics and Ceramic fabrics.

Glass fabrics with Vermiculite coating are also available. These blankets can also be provided with loops for hanging or with eyelets.

Cable Protection Sleeves are used to protect cables and hoses from high heat, molten metal splashes, occasional flames in nearby areas. These sleeves are made from Heat Resisting fabrics.

The sleeves are also made to suit particular size of cable or hose that are already installed at customer’s site.

The sleeves are generally made from Silicon Rubber Coated Glass Fabrics. For higher temperatures, High Silica Fabrics and Ceramic Fabrics are used.

Cable Protection Sleeves can be supplied with Velcro, Steel Buttons or can be Stitched at site so that they can be fitted on cables which are already connected in the system. Such methods of installation bring extra convenience.

As described by Fluid Sealing Association-USA, “Non-Metallic/Fabric Expansion Joints are flexible connectors designed to provide stress relief in ducting systems by absorbing movements caused by thermal changes. They also act as vibration isolators, shock absorbers and in some instances to make up for minor misalignment of adjoining ducting or equipment.” Fabric Expansion Joints are typically designed for ducts where pressure is know, not more than 3 psi (2000 mm w/c) and temperature up to 1000oC. However, for higher temperatures, duct itself needs to be internally insulated.

A technical joint venture has been signed with Senior Flexonics Pathway-USA, who is globally known in the field of expansion joints. We bring to India their experience of over 50 years in this field. Today, Urja is registered and regularly supplying to prestigious organizations like BHEL, EIL, NTPC, RELIANCE, TATA, L&T, GAIL, IOCL, MRPL, GSFC, IFFCO etc. etc.