national diamond core drill bit - all

Impregnated Bit Sharpening Technique

Where the matrix type and waterway configuration have been correctly selected for a drilling job, an impregnated core bit should drill steadily with an even wear pattern until the matrix layer is totally consumed. At this point, the circulating pump pressure will usually increased due to the fluid restriction caused by the diminished waterway depth on the bit face.

If the matrix type and/or waterway configuration is not exactly suited to the formation conditions, it may become necessary to sharpen the bit face in event that the penetration rate becomes unacceptably low. A decrease in penetration rate is usually caused by the diamond crystals on the bit face becoming blunt. The metal bond matrix is probably too hard for the formation conditions and will not erode at a controlled rate to expose new layers of diamond crystals. If possible, change to another D-Series or HR-Series bit with a softer (higher number) matrix type and/or a bit with a lower face contact area that has a more open waterway configuration such as the ‘Turbo’ style.

If it is not possible to change the bits, it will be necessary to sharpen the bit face using one of the following methods. Bit sharpening techniques should only be used when absolutely necessary as they tend to have an

How to adverse effect on Impregnated Bit overall life for using.

Method 1 – Bit Face Dressing (Preferred Method)

Remove the bit from the drill hole and sandblast the face with an abrasive media such as Aluminum-Oxide or Silicon-Carbide grit. If sandblasting equipment is not available on site, use a tapping action with a flat file to roughen the surface of the bit.

Method 2 – In-Hole Method

impregnated diamond core bits advantages:

1 An extremely wide range of application.

2 A simple crown geometry that makes them less susceptible to in-hole damage than bits produced with other types of cutting media and a such are more tolerant of changing or banded geological formations.

3 Their multi-layered cutter arrangement results in better overall bit life than the bits that produced with other types of cutting media. They are particularly well suited for drilling in hard formations, consolidated, non-abrasive formations.

With the bit on the bottom of the drill hole and with the drill string rotating, reduce the rotational speed to about 50% to 75% of the hole normal rotational speed. Try to maintain a constant rate of penetration for a distance of 6 to 50 mm (0.25 to 2 inch) allowing the bit load to gradually increase and then suddenly decrease thus indicating that the bit face has sharpened and will now cut freely. IMPORTANT: It imperative that at the instant this sharpening (bit load decrease) occurs, the applied bit load must be decreased and the rotational speed must be increased to their original values. Failure to make this adjustment will result in further stripping and could cause a premature failure of the bit .In extremely hard formations with a high Silicate content, it may be necessary to reduce the fluid circulation rate below recommended values in order to maintain bit sharpness

Size Available:

"Q" series:AQ,BQ,NQ,HQ,PQ/AQTK,BQTK,BQ3,NQ2,NQ3,NQTT,HQ3,HQTT,PQ3,PQTT
T2 series: T2 46,T2 56,T2 66,T2 76,T2 86,T2 101
T6 series: T6 76,T6 86,T6 101,T6 116,T6 131,T6 146, T6S 101,T6S 116
T series: T36,T46,T56,T66,T76,T86
Z series: Z46,Z56,Z66,Z76,Z86,Z101,Z116,Z131,Z146
B series: B36,B46,B56,B66,B76,B86,B101,B116,B131,B146
WF series: HWF,PWF,SWF,UWF,ZWF
WT series: RWT,EWT,AWT,BWT,NWT,HWT
WM series: EWM,AWM,BWM,NWM,HWM
WG series: EWG,AWG,BWG,NWG,HWG
Others: NMLC,HMLC,LTK48,LTK60,BGM,NGM,ADBG,TBW,TNW,
ATW,BTW,NTW,NXD3,AX,NX,NXC,AXT,T6H,4 9/16,NWD4,412F,SK6L146,
TT46,TB56,TS116,CHD10