Recycling Symmetric Overburden Casing System

• Customization: Available
• Customized: Customized
• Standard: API
• Model NO.: SOD
• Length: Jobber-length
• Type: Center Drill Bit
• Material: Tungsten Carbide
• Usage: Well Drilling
• Transport Package: Carton
• Trademark: BESTLINK
• Origin: Xiamen Fujian
• HS Code: 70161000
• Production Capacity: 1000set/Year

Product Description

The Symmetric drilling system is designed to drill and case a hole simultaneously through unstable ground conditions. The driver bit incorporated with a satisficial ring or reusable ring makes a full face head design which significantly improves the penetration rate and hole straightness of drilling. The internal flushing grooves together with the built-in casing shoes gives a good seal to the button of the drilling hole, and thus minimizing the disruption of the surrounding of the drill hole. 

Application Range: It is suitable for drilling water wells , geothermal wells , short miscopies ,medium mini-type grouting hole of building , dam and harbor project . 
1. Ring bit and casing shoe assembly is welded to casing prior to drilling. Lock the assembly into pilot bit with hammer. The pilot bit's upper shoulder engages the shoulder of the casing shoe. 
2. Hammer's percussive energy is transferred through the pilot and ring bits, crushing rock . Part of impact energy advances casing. 
3. On completion of drilling and casing , the drill string with pilot bit is retrieved by a slight reverse rotation to unlock the bayonet coupling . The ring bit stays in the hole , and can be recovered only if the casing is retrieved 
4. Drilling continues to the desired depth in the bedrock using a conventional drilling.

 

Outer Dia. of Casing Tube	Inner Dia. of Casing Tube	Reamed Dia.	Min. Inner Dia. of Casing Shoe	Drill Pipes	Max. Outer Dia. of Normal Bit
mm	Mm	mm	mm	mm	mm
108	93-99	118	86	76	77
114	101-103	127	91	76	82
127	114-116	136	101	76	92
140	124-127	152	117	76	105
146	127-132	154	117	76	105
168	149-155	184	140	76,89	125
178	159-165	194	150	76,89	140
193	173-180	206	164	89,114	150
219	199-206	234	184	89,114	165
244	224-231	260	210	114	190
273	251-257	305	240	114,127	220
323	301-310	348	284	127	255
406	382-388	440	364	140	340
457	433-439	488	413	140	385
508	484-490	538	464	140	440