Dolomite abrasion

Select a tungsten carbide insert bit with no offset and conical or double cone inserts when drilling hard and abrasive limestone, hard dolomite, chert, pyrite, quartz, basalt, etc. Use bit type 7-4 to 8-3. 

Particles char, ash and gasification additives such as sand, limestone or dolomite resulting in plugging and abrasion of downstream equipment. 

Abrasion can be serious when using mineral fillers. Fillers with alpha-quartz components have by far the highest abrasion rate, but heavy and tabular spars and dolomite also show high abrasion compared with some calcium carbonates. The measurement value usually cited is the Mohs hardness scale, but this is not a decisive indicator. 

Wollastonite and diopside are utilized as abrasion-resistant materials for road surfaces and fillers for rubber and plastics (Jacob, 1976), and also as thermally insulating materials for a variety of applications (Demidenko et al., 2001). Currently, these calcium and caldum magnesium silicates are synthesized starting with mixtures of moist lime (CaO) or burned dolomite (CaO + MgO) and finely ground quartz flour. The mixtures are heated hydrothermally between 200 and 250 °C for 7-16 h to yield xonotlite or mixtures of xonotlite and serpentine according to >... 

The primary mineral fillers and reinforcements in plastics are calcium carbonate, kaolin, talc, mica, wollastonite and silica. Calcimn carbonate is by far the mineral most commonly used to fill plastics. This is mainly because it is low in cost, widely available and provides a good balance of properties. Calcium carbonate may be pure or in combination with magnesium carbonate as a dolomitic limestone. Dolomitic limestone is harder than pure calcium carbonate and is preferred when abrasion resistance is needed, as in floor tiles. 

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