Drill collar:
Our drill collars are manufactured from 4145H modified steel.Drill collars are bored and drifted to API Spec7-1 and fully heated to meet or exceed the mechanical property requirements of API Spec7.Hardness range of 285-341HB and a charpy V notch impact value of 54joules are guaranteed one inch below the surface.
On enquiries and orders ,please specify:
Slick or spiral;
Drill collar OD;
Drill collar bore:
Length of drill collar;
Connection type;
Stress-relief grooves:
Stress-relief grooves decease the frequence of fatigue failures by improving the bending strength of pin and box connections and reducing high stress concentrations.Sress-relief features are manufactured in compliance with API Spec7,unless otherwise specified by customers.
Slip recess and elevator recess :
Shenlong offers optional elevator and slip recesses to improve handling efficiency and safety.The
upper radius of elevator recess is cold-rolled to increase product life.Slip and elevator recesses can be used together or seperately.Unless otherwise specified,slip and elevator recesses are machined in compliance with API RP7G guidline.
Our drill collars are manufactured from 4145H modified steel.Drill collars are bored and drifted to API Spec7-1 and fully heated to meet or exceed the mechanical property requirements of API Spec7.Hardness range of 285-341HB and a charpy V notch impact value of 54joules are guaranteed one inch below the surface.
On enquiries and orders ,please specify:
Slick or spiral;
Drill collar OD;
Drill collar bore:
Length of drill collar;
Connection type;
Stress-relief grooves:
Stress-relief grooves decease the frequence of fatigue failures by improving the bending strength of pin and box connections and reducing high stress concentrations.Sress-relief features are manufactured in compliance with API Spec7,unless otherwise specified by customers.
Slip recess and elevator recess :
Shenlong offers optional elevator and slip recesses to improve handling efficiency and safety.The
upper radius of elevator recess is cold-rolled to increase product life.Slip and elevator recesses can be used together or seperately.Unless otherwise specified,slip and elevator recesses are machined in compliance with API RP7G guidline.
Specifications
- number and commection label
- from NC23-31 to NC70-100;from 6 5/8REGto 8 5/8 REG
- outside diameter(in)
- from 3 1/8 to 11
- bore(in) +1/16;-0
- from 1 1/4 to 3
- Length(ft) +6in;-6in
- 30 or 31
- bevel diameter
- from 3 to 10 1/2
Features
- slick,spiral,non-magnetic
- we can supply slick drill collar,spiral drill collar,and non-magnetic drill collar.
- slick and spiral drill collar
- 4145H modified steel;bored and drifted to API SPEC7-1;fully heated to meet the mechanical property requirements of API Spec 7;hardness range of 285-341HB;charpy V notch impact value of 54 joules
- non-magnetic drill collar
- The material is chrome manganese stainless steel.High quality is achieved by two process,material choosing and material inspection.
- During steel making,chemical components are seriously controlled.The most important process to make our non-mag products outstanding is forging process.Professional forging techniques assure the mechanical properties of our non-mag products meet API standard.
- All materials have been ultrasonic tested within the whole length to make sure there is no crack inside.
- magnetic permeability
- We cooperate with the National Institute of Metroloty P.R.China in measurements of relative magnetic permeability.And our non-mag products have a relative magnetic permeability less than 1.010.
- We refer to GB4334.5-2000.ASTM.A262,ASTM.A276 when doing corrosion resistance experiments and we can reach the best condition.
Certificate
- We offer API standard products and services
Main Products
drill collar,drill pipe,stabilizer,drill stem subs,kelly