Knife dressed Sheet Mica of a minimum thickness of 0.18 mm (0.007 Inch), is called Block Mica or Mica Blocks. Block Mica is obtained in size as large as 30 to 35 cm. sq. (12 to 14 Inches sq) beyond which is practically rare and far too expensive. It is available in sheets with an average thickness between 0.18 - 0.75mm (0.007 - 0.030 Inch). Block Mica is supplied both in natural (random) and calibrated thickness as per customers demand.

These are the mica blocks of various different origins in India. They all have mostly similar properties besides the color & temperature resistance. Their dielectric properties differ too. ruby mica is the most sustainable in all forms across all types.

The term 'Fabrication' applies to operations, such as: cuttings, stamping and punching of natural sheet mica to specified size, shape, thickness and design within close dimensional tolerance for electrical and electronic end-users.

Normally, mica is fabricated with compound dies by foot or power punch process, especially if the finished piece contained perforation of any kind. A compound die punches the outside shape and all the inside holes with one stroke of the press most accurately. The compound die necessary for stamping natural sheet mica may be grouped in two general categories. One category comprises the highly complex dies required to produce Mica Spacers containing a number of perforations in various sizes and shapes for use in electronic tubes. The extremely critical dimensions and spacing of the perforations can be obtained only with fully designed and accurately constructed dies.

The natural structural stability in mica renders it the perfect dielectric with outstanding features of low leakage, great stability under increasing temperature, high insular strength, low rate of solar impurities and reasonable admittance factor. Because of these outstanding features, mica is most suited for use in thermionic valve bridges, cathode ray tube assemblies, condenser plates, domestic elements, stove plates and washers built upto any thickness. In almost all these applications, mica is die-punched and used as such, or with a coating.

Mica Shields provide the best protection possible, to flat transparent, sight glasses in water and liquid level gauges and columns in high pressure steam boilers. The Shields retain basic strength and increase the service life of sight glasses when used at increased steam pressures and high working temperatures. Mica Shields also provide perfect visibility for monitoring the natture or degree of combustion in blast furnaces of steam boilers.

Natural mica has extremely high heat resistance; transparency ; optical clarity ; flexibility ; flatness and is unbreakable. The transparency of mica is not affected by the repeated fluctuations in heating and cooling and is not attcked by most of the gases and vapours it might come into contact with. In addition, mica resists shocks, strains and vibrations and therefore can easily be used in place of glass where there is a likelyhood of exposure to radiant heat, breakage or cracking. As steam boilers are frequently shut-down and started up again, this places extreme demands on the transparent glasses fitted between CAF sealing gaskets and cushion joints of the level gauges. It is therefore essential to protect these glasses with Mica Shields by fitting them on the side facing the medium chamber. Mica Shields are a must where saturated steam pressure exceed 350 psi (up to 5689 psi) and working temperatures exceed 196 deg. C (up to 600 deg. C).

Mica Shields also protect the inner surfaces of the transparent glasses against erosion from chemical abrasion and from corrosive chemical effects of alkaline solutions, boiler waters, caustics, hydrofluoric acids, hot concentrated phosphoric acids, sodium and potassium hydroxides and other contaminated viscous or corrosive media. It provides an excellent sealing strength against acids, sodium, water, air and oil at extreme pressures and temperatures and completely eliminates the risk of cracks, breakage, jerks, shocks, combustion effects, etc. In fact, Mica Shields serve effectively in closing the spy holes of observation doors of level gauges and columns.

KPR brand Mica Shields are made of the highest quality natural muscovite sheet mica. Our Shields are transparent and colourless having a high degree of through-vision transparency and thus guarantying optimum visibility of the level gauges and columns. In terms of purity, our MICA SHIELDS meet the requirements of ASTMD 351 -57T, MIL-G-18498C(SH) and ISO-2185-1972. They are supplied in any desired length, width and tickness to meet our clients specific needs. Each MICA SHIELD is rigidly tested and inspected for quality and reliability befire despatch and is supplied in individual packets to eliminate scratching and to protect them against damage. A multi- language installation and maintenance guide is included in each package.

Micanite is the name given to sheet material which is made up of fine mica lamellae, called “Mica Splittings”, bonded together by a variety of bonding agents such as Shellac, epoxy, alkyd or silicone, in order to obtain particular characteristics for specific uses. Variations can be made in the method of manufacture, the types of Mica, and the type of quantity of bonding material used to form thick or thin, stiff or flexible products in the form of sheets, webs or ribbons and also moulded articles.