Grant Prideco

	2007 ReedHycalog Rig Census
	Press Releases 03/10/2008: National Oilwell Varco and Grant Prideco announce early termination granted 02/29/2008: GRANT PRIDECO REPORTS EPS OF $1.00 PER SHARE ON A 12% REVENUE INCREASE 11/09/2007: Grant Prideco Elects Gordon Hall to its Board of Directors

	" IADC/SPE 92497 Project-Specific High-Pressure Completion Tubular for ChevronTexaco's Tahiti Project"
	"IADC/SPE 92575 The Effect of Extreme Make-up Torque on Performance of Rotary Shouldered Connections"


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H-SERIES^® Drill Collar Materials

Materials Mechanical Properties
Drill Collar Diameter in.	Minimum Yield Strength psi.	Minimum Tensile Strength psi.	Minimum Hardness BHN.
3 1/8 thru 6 7/8 7 thru 11	110,000 100,000	140,000 135,000	285 285
Tensile properties are determined by tests on cylindrical specimens conforming to the requirements of the current ASTM A370, 0.2% offset method. Hardness tests are performed on the OD of aft drill collars in compliance with current ASTM standards.

H-SERIES drill collars are manufactured from AISI 4142H-4145H modified steel and are supplied in the "as rolled" surface finish condition. Alternative surface finishes can be provided. Drill collars are trepanned and drifted to API Spec. 7. Full-length heat-treatment processes ensure that mechanical properties meet or exceed API Spec. 7 requirements. A hardness range of 285-341, Brinell Hardness and Charpy "V' notch minimum impact strength of 40 ft-lb at 70°F are guaranteed one inch below the surface.

Traceability
H-SERIES drill collar material and process traceability are maintained from receipt of mill certified raw material to completion of all the manufacturing. Serial numbers are die stamped on bar bodies.

Rigid Inspection Procedures
We inspect all our H-SERIES drill collars to comply with API standards and our own internal specifications. These inspections include visual dimensional checks as well as ultrasonic inspections over the entire body of the drill collar.