Concentric Overburden Drilling Systems for Construction

• Customization: Available
• Type: Center Drill Bit
• Material: Tungsten Carbide
• Model NO.: COD168, COD274
• Usage: Well Drilling
• Model: Cod168, Cod274
• out Dia: 168-325mm
• Inner Dia: 148-309mm
• Reamed Hole Dia: 185-378mm
• Casing Shoe Inner Dia: 140-281mm
• Carbide: Yk05
• Transport Package: Wood Package
• Specification: CE, ISO9001
• Trademark: prodrill
• Origin: China
• HS Code: 82071990
• Production Capacity: 5000PCS/Month

Product Description

Description:
Prodemo has developed a range of Concentric Overburden Drilling Systems for the continuous casing of medium to large diameter holes-up to 378mm diameter. The equipment gives excellent performance for drilling through loose overburden materials down into solid bedrock. At the start of the drilling operation, the seat against the casing shoe, When drilling commences, the segments swing out to drill the hole to the PESired diameter. The machines can be withdrawn through the casing by rotating the system anti-clockwise against the solid base of the hole or up against the casing shoe.

Application Range:It is suitable for drilling water wells , geothermal wells , short mircopiles ,medium mini-type grouting hole of building , dam and harbour project .

1. When drilling starts , the reamer swings out and reams the pilot-hole wide enough for the casing tube to slide down behind the drill bit assembly
2. When the required depth is reached , rotation is reversed carefully, whereupon the reamer swings in , allowing the drill bit assembly to be pulled up through the casing.
3. Casing tubes that are to be left in the drill hole should be sealed at the bottom of the hole by means of cement grout or some other sealing agent.
4. Drilling continues to the desired depth in the bedrock using a conventional drilling.

Technical Data

 

 

Overburden Drilling Systems-Concentric Casing
Technical Data
Casting Tube		Reamed Hole Dia(mm)	Casting Shoe Inner Dia	DTH Hammer Type(E)	Drill Pipe(mm)
Outer Dia(mm)	Inner Dia(mm)
168	148-156	185	140	HD55 QL50	89
178	158-166	195	150	HD55 QL50	89
183	163-171	193	154	HD55 QL50	89
194	174-182	211	166	HD65 QL60	114
219	199-207	237	193	HD65 QL60	114
245	225-233	260	210	HD85 QL80	114
273	253-257	308	241	HD85 QL80	114
325	305-309	378	281	SD10 NUMA100	114