Casing Bit & Casing Shoes Bit is used on the leading edge of a casing tube string to advance it through the overburden layer and into the bedrock by means of rotational drilling. Depending on the range of application, the cutting media on the core bit may take the form of synthetic diamond on the impregnated type, natural drill diamond on the surface-set type, or tungsten-carbide particles or elements.
Depending on the cutting media, Forsun makes four types of Casing & Casing shoe & Rod Shoe Bits:
- Impregnated Diamond Casing & Casing shoe & Rod Shoe Bits
- Surface set Casing & Casing shoe & Rod Shoe Bits
- Tungsten Carbide Casing & Casing shoe & Rod Shoe Bits
- Electroplated Diamond Casing & Casing shoe & Rod Shoe Bits
Impregnated Diamond Casing Shoe Bit is the most commonly used as it has the widest range of application and is generally the most efficient tool for advancing casing through overburden layers. IDP manufactures impregnated diamond casing shoe Bit that may be used with all sizes of standard casing tubes. The basic construction of these casing shoe Bit features a sintered powdered metal crown that is fused to a steel tool body or shank.
Surface-set diamond casing shoe Bits are recommended for use when drilling relatively soft and abrasive formations such as sandstone or limestone. The diamonds are embedded in a powdered metal matrix body tool crown that is fused to a steel tool body.
Tungsten-Carbide Casing Shoe Bit. This type of casing shoe Bit uses seismic grade tungsten carbide as the cutting media. Tungsten carbide does not possess the hardness of diamond and as such has a limited range of application as a drill tool cutting media. Tungsten-carbide casing shoe Bit are however a very cost effective means of drilling through softer unconsolidated formations.
|Standard Casing Shoes|
|Size||Outside||Inside Set Diameter|
|RW*||1.475 /1.465||37.46 / 37.21||1.188 /1.183||30.18 /30.05|
|EW*||1.880 /1.870||47.75 / 47.50||1.497 /1.492||38.02 /37.90|
|AW*||2.350 /2.340||59.69 / 59.44||1.902 /1.897||48.31 /48.18|
|BW||2.970 /2.960||75.44 / 75.19||2.377 /2.367||60.38 /60.12|
|NW*||3.620 /3.610||91.95 / 91.70||2.997 /2.987||76.12 /75.87|
|HW* DCDMA||4.632 /4.617||117.65 /117.27||3.980 /3.970||101.09 /100.84|
|HWT||4.632 /4.617||117.65 /117.27||3.930 /3.920||99.82 / 99.57|
|PW**||5.660 /5.640||143.76 /143.26||4.865 /4.850||123.57 /123.19|
|SW*||6.800 /6.780||172.72 /172.21||5.948 /5.933||151.08 /150.70|
|UW*||7.815 /7.785||198.50 /197.74||6.916 /6.896||175.67 /175.16|
|ZW*||8.825 /8.795||224.15 /223.40||7.987 /7.967||202.87 /202.36|