What - Why - HowThread Compounds

Mark MulvihillResearch & Development ManagerBestolife Corporation 2008

• Rotary shouldered connections

• Tubing and casing

• Threads in storage

— Thread Compounds —Important Jobs:

— Lubricate — ProtectSeal

Connections Should:

• Prevent metal to metal contact

• Provide a leakproof seal for fluids

• Limit make-up during drilling to prevent excessive stresses on threads

• Prevent corrosion of threads

• Ideally, breakout less torque than make-up

• Leave no residue or plating at breakout

— Rotary Shoulder Connections —

Compounds Need :

• Ingredients that should mould into threads, produce a seal, and reduce thread contact

• To be slick enough to lubricate threads during make-up but provide sufficient resistance to make-up under torque

— Rotary Shoulder Connections —

Compounds Seal:

• Additives that are spherical in shape. • As the joints are torqued, the additives are flattened & elongated

bonding together on the shoulders of the pipe, preventing metal to metal contact.

• The angular make-up at given torque controlled by the compound type

• Dispersed particles embrittle compact upon breakout and do not stick to it make-up under torque

— Rotary Shoulder Connections —

Compounds Should Have :

• Sealing and galling prevention are most important functions of a thread compound

• Metallic powdered compounds will deform to seal and reduce galling of threaded connections

• Non-metallic compounds rely on solids like Graphite, Talc, and others to seal and eliminate galling

— Rotary Shoulder Connections —

Make-Up of Connections:

• Sealing and galling prevention are most important functions of a thread compound

• Metallic powdered compounds will deform to seal and reduce galling of threaded connections

• Non-metallic compounds rely on solids like Graphite, Talc, and others to seal and eliminate galling

— Rotary Shoulder Connections —

Uncontrolled Make-Up:

• When the make-up torque of the tool joint is less than the drilling torque, it can make-up down hole and may be difficult to breakout

• Uncontrolled make-up down hole can damage a tool joint and cause a drill string to break down hole

— Rotary Shoulder Connections —

Make-Up Lubricity :

• Thread compounds need to decrease the friction between contacting surfaces

• For small diameter drill pipe, lubricity is not a major factor

• For large diameter drill pipe, high surface area, a low coefficient compound can reduce friction and help with make-up

• When joints are made up too far, severe damage can result

— Rotary Shoulder Connections —

Breakout:

• Ideally, breakout torque should be less than make-up torque

• If a joint makes up down hole, the breakout torque can be higher than the make-up torque and the original make-up equipment may not be able to breakout the joint

— Rotary Shoulder Connections —

Compound Properties:

• Lead based – Lead provides seal, and make-up stress energy is absorbed. Can be used on both collars and pipe.

• Zinc based – Zn is a reactive metal, and can have problems when temperature and moisture are present. Can be used on both collars and pipe.

— Rotary Shoulder Connections —

Compound Properties:

• Copper based – can be used on collars and pipe. Can withstand higher temperatures than Lead or zinc.

• Non-Metallic – additives take the place of metals to provide the seal, more environment & worker safe, non-reactive, non-hazardous for offshore.

— Rotary Shoulder Connections —

Environmental Compounds:

• No metals – Lead, Zinc, or Copper• Ingredients that cause no harm to environment• Biodegradable components• Non-toxic to marine organisms• No labels required for disposal• No Toxicity Characteristic Leaching Procedure

required

— Rotary Shoulder Connections —

Environmental Regulations:

• Offshore Drilling – Regulations are more strict

• Worldwide – many countries are regulating the use of hazardous materials

— Rotary Shoulder Connections —

Environmental Regulations:

• Land rig waste disposal is becoming more regulated

• Some companies are standardizing on the same thread compounds worldwide

— Rotary Shoulder Connections —

API Bulletin 7A1:

“Recommended Practice for Testing of Thread Compounds for Rotary Shouldered

Connections” - is used to determine the frictional properties of thread compounds

— Rotary Shoulder Connections —

API Bulletin 7A1:

• 7A1 is still being revised and a new tester & test method are being developed

• API SC 7 provides drillers with friction factors that help predict actual make-up and breakout torques required

— Types of Compounds —

Environmental Regulations:

• API Modified – Lead/Zinc/Copper product recommended by API for use API 5A2

• API 5A3 – allows for different compounds that meet performance specifications

— Tubing & Casing Thread Compounds —

Should Provide:

• a long term seal on the threads to prevent leaks

• protection against galling on the threads

• protection against corrosion to the threads

— Tubing & Casing Thread Compounds —

Environmental Regulations:

• API Modified 5A2 – reduced usage of this product due to heavy metal content. Alternative is API 5A3.

• More environmental products are used mainly, either copper or non-metallic

• Standardization by oil and tubular companies worldwide

• Move towards environmental products is strong

— Tubing & Casing Thread Compounds —

New Solutions

• Rusting threads in storage have been a major problem for all drillers

• Thread compounds are seldom compatible with currently available storage compounds

• Bestolife BSC provides 2000 hours of Salt Spray protection which is equivalent to 2 years of storage and is compatible with most thread compounds

Twenty-First Century Compound

• Rusting threads in storage have been a major problem for all drillers

• Thread compounds are seldom compatible with currently available storage compounds

• Bestolife BSC provides 2000 hours of Salt Spray protection which is equivalent to 2 years of storage and is compatible with most thread compounds