Darron Drill Collars are manufactured from
Chromium, Molybdenum Alloy Steel conforming to
AISI 4145 H Modified. Fully heat treated and
supplied in accordance with A.P.I. Specification
Quality Control and Ultrasonic Inspection
State of the art measurement and ultrasonic techniques are used to ensure that the highest control standards within the industry are maintained.
Every Darron Drill Collar is subject to full length, full section ultrasonic examination. Thread connections machined and gauged in accordance with A.P.I. Specification 7-1 and RP7G are individually examined within our own inspection department as an integral part of final inspection procedures.
Individual characteristics of each thread such as
stand off, taper, pitch, etc., are fully
documented on in-house documentation.
All connections are machined to the highest possible accuracy and conform to the requirements of A.P.I. Specification 7-1& 7-2.
To improve fatigue resistance all connections are
cold rolled and to prevent galling during make up
all connections are phosphated. Connections are
coated with a thread compound conforming to the
thread protectors are fitted.
Drill Collars are deep precision bored to ensure
tight tolerances that eliminate wall thickness
variation along the bar length and drifted to
A.P.I. Specifications. In addition to the
standard ranges shown on following page, special
sizes, bores, connections and lengths can be made
to meet customers' specific requirements.
The surface finish, linear straightness,
roundness and O.D. tolerances conform to A.P.I.
Licensed to apply the A.P.I. monogram Darron also mark the Drill Collars unique identification serial number, O.D., I.D., size and style of connections.
Downhole Tools: Heavy Weight Drill Pipe (Integral)
Darron's supplier in India offers a complete range of heavyweight drill pipe is integral and manufactured from AISI 4145H fully heat-treated steel that conforms to all API Spec. 7-1 standards
Downhole Tools: Rotary Crossover Subs
Darron Drill Stem Substitutes are manufactured from Alloy Steel AISI 4145 H Modified conforming to the requirements of A.P.I. Specification 7-1.
Downhole Tools: Lift Subs & Lift Plugs
The Darron Lift Subs are manufactured from AISI 4145 H Modified Steel, fully heat treated and supplied in accordance with A.P.I. Specification 7-1.
Downhole Tools: Circulating Subs
The Darron Circulating Subs have been designed to achieve increased mud circulation by placement in the B.H.A., either above the bit or down hole motor to pump materials in case of lost circulation.