Symmetric overburden system is a system comprised of an ingeniously simple concentric method of drilling through overburden with casing. Symmetric can drill straight holes at any angle (including horizontal) and to depths beyond 100 meters. Working together as one efficient drill bit, the components are made up of:

1.A pilot bit with large internal flushing holes and external flushing grooves.

2.Symmetrical ring bit (reamer) with internal bayonet coupling.

3. Casing shoe for driving of casing.

A brief introduction of Symmetric Casing system:

1．  When the drilling starts,the central bit drive the ring bit down to the hole follow down together.

2．  When arriving the bedrock,reversely rotate the tools and the central bit is pulled down from the hole

3．  During pouring the concretes through the casing tube,pull out the casing tube with the ring bit synchronically.

Quick details:

Bit Face Shape Selection 

1. Drop Center Bit

2. Concave Face

3. Convex Face

4. Double Gauge Face

5. Flat Face Bit

Carbide Button Shape Selection 

1. Domed/Round Button
2. Parabolis/Semi-Ballistic Buttons

3. Ballistic Buttons

4. Sharp Buttons

5. Flat Buttons

Features:

1.Efficient energy transfer .
2.Faster drilling speed .
3.Lower oil consumption. 
4.Longer service life,less failure.

5. reliable performance and fast drilling rate.

About Us:
1. Our factory has been specialized in manufacturing & exporting drilling tools and spare parts over 10 years. And passed ISO9001 quality management system certification.

2.We adopt advanced production technology & strict testing procedure.

3. Our technician has more than 10 year's professional working experience.

4. We accept OEM manufacturing and produce on your design.

Questions you may be interested in:

1.Payment: T/T,Western Union,Paypal

2.Delivery time: Based on your order qty, generally it takes 15-20 days for

production.only need 2 or 3 days if it’s available in our stock.

3.Shipment:

Trail order: we suggest by DHL,express

Bulk order: we suggest by sea.

4.Quality control: We have our experienced QC Dep.

They will perform stick inspection and tesing for every order before shipping out.

5. About aftersale services

Our sales team and technical Dep. Will be available at any time.(Holidy excluded)

If you need more informatin about our products,Pls kindly contact us on skype

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