| Place of Origin: China (Mainland) | Brand Name: Kingdream,CS,Lilin | Model Number:HAT 447G |
| Type:Center Drill Bit | Material:Carbon steel | IADC Code:447 |
| size: 6 5/8" (168.3mm) | Pin shank size:3 1/2reg | Normal WOB:0.35-1.00KN/mm |
| Rotary speed:140-60r/min | Types of Sealing:Rubber sealing | Types of Bearing:Sliding bearing |
| MOQ:1 piece | color: as your requirements | Use:Well Drilling |
The differences between sealed bearing bits and non-sealed bearing bits
1.Standard Open Roller Bearing
Standard open roller bearings are bearings without a seal. This means that the
bear-ings are open to outside debris, which can enter through the cone.
The advantage of an open bearing bit is that they are usually cheaper.They are
ideal for drilling shallow holes, in the hundreds of feet. If drilling deeper holes
with an open bearing bit you will probably have to pull it out every couple hundred
feet to clean out the debris in the cones to free them up.
2.Air Cool / Air Blast Bearing
Air Blast Bearings are equipped on Air Circulation Bits.These bits have air
passage that supply air to the bearings for cooling and lubricating of the bearing,
and for cleaning of the bearing from the drilling debris.
3.Sealed Journal Bearings
Sealed Journal Bearings have very good durability and wear resistance. Instead
of rollers inside the cone there is a floating bushing.
The bushing is usually made out of special material that is highly resistant to
heat and galling (surface damage).
