Troubleshooting - Boart Longyear

Troubleshooting

Stand-Off Gap Excessive or Dos Not Close Upon Minimal Make-Up or Difficulty Breaking Out.

CONVENTIONAL AND Q^TM	ROD RQ^TM AND RQ^TMTK ROD
Clean and inspect threads for excessive foreign or wear debris. Accelerated wear may be due to damaged accessories (e.g. adapter subs).
Rods are of different manufacture. Separate all rods by manufacturer and do not interchange.RQ^TM style joints are proprietary to Boart Longyear.
Threads are deformed from overload or excessive load during make and break. Inspect string for damage and discard rods with deformed threads. Overload or difficult breaking may be due to poor choice of thread compound (see lubrication andcleaning and break-out).
Deformation due to hammering damage (see break-out) or stabbing damage (see stabbing). Inspect string and discarddamaged rods.

Leakage (see Fluid Seal)

CONVENTIONAL AND Q^TM	ROD RQ^TM AND RQ^TMTK ROD
Rods run in loose (joints not closed) due to insufficient make-up or to excessive stand-off gap (see causes of excessive stand-off above).
The pin or box outer diameter shoulder face has stabbing or handling damage (see stabbing).
Outer shoulder contact pressure distribution is uneven due to poor fit. Threads are significantly worn or deformedfrom overload or excessive load during make and break (see thread wear) or shoulders are deformed from overload. Accelerated wear may be due to damaged accessories; inspect accessories e.g. adapter subs. Inspect string for excessivewear (see thread wear). Overload may be due to poor choice of thread compound (see lubrication and cleaning). If using Q^TM, consider upgrade to RQ^TM rods.
Box wear life exceeded. Inspect string for excessive wear. Consider upgrade to RQ^TM rods.
Rods are of different manufacture. Separate all rods by manufacturer and do not interchange. RQ^TM style joints are proprietary to Boart Longyear.

Fatigue Failures or Cracked Pins or Boxes (see Fatigue Strength)

CONVENTIONAL AND Q^TM	ROD RQ^TM AND RQ^TMTK ROD
Bend stresses have exceeded the fatigue strength of the joint. Bend stresses are caused by excessive steering, excessive hole deviations or caves, or helical whirling (see midbody wear). Do not exceed deviation ratings. This may have beencompounded by high pullback loads at depth or excessive make-up. Plan deviations to occur at portions of the string thatare under low pullback (e.g. avoid the upper portion of a deep hole string). Fatigue strength may have been exceeded in previous application and joint has now reached limit (see memory and fatigue strength). Consider upgrading to RQ^TM, joints for higher load capacity or consider lightweight rods for reduced stiffness.
Rods run in loose (joints not closed) due to insufficient make-up or to excessive stand-off gap (see causes of excessive stand-off).
Extraneous hoop stresses (see glossary) caused by deformation due to hammering damage (see break-out), stabbing damage (see stabbing), excessive foreign debris, or wear debris in the joint (see thread wear).
Box shoulder deformed due to overload leaving pin or box unsupported. Overload may be due to poor choice of thread compound (see lubrication and cleaning). Consider upgrade to RQ^TM rods.
Box wear life exceeded. Inspect string for excessive wear (see wear life).
Rods string has suffered from hydrogen embrittlement (see glossary). Replace rod string and use non-metallic thread compound.
Rods are of different manufacture. Separate all rods by manufacturer and do not interchange.RQ^TM style joints are prprietary to Boart Longyear.

Premature Box End Cracking / Heat Check Cracking

CONVENTIONAL AND Q^TM	ROD RQ^TM AND RQ^TMTK ROD
Axial cracks at the box end due to a change in micro-structure of the tubing material. Change in microstructure is causedby the cyclic friction between the rotating string and the casing or hole wall and is independent of tubing type, steel gradeand/or applied heat treatments. Reduce drilling loads and/or pullback, or improve lubrication of the string to compensate.

Thread Wear or Galling (see Thread Wear)

CONVENTIONAL AND Q^TM	ROD RQ^TM AND RQ^TMTK ROD
Thread compound has failed to prevent mating thread surfaces from interacting. This is due to either a poor or diluted compound or poor lubrication practice. Upgrade thread compound or increase frequency of cleaning and re-lubing joints
Thread contact pressure is excessive. For stab flank wear, reduce feed rate/pressure and/or increase rotation during makeand break. For load flank wear, increase feed rate and/or reduce rotation during make and break. Rods with significant load flank wear should be discarded.
Thread sliding contact is excessive (e.g. too much drag during make/break turns) or frequentjamming or cross-threading. Consider upgrade to RQ^TM syle joints.	RQ^TM style joints have the greatest joint taper (e.g. fewest make/break turns) available in the industry and have anti-jamming geometry.
Accelerated wear may be due to damaged accessories; inspect accessories for damage or wear (e.g. adapter subs).
Thread wear life exceeded. Accelerated wear may be due to damaged accessories; inspect accessories (e.g. adapter subs). Inspect string for excessive wear.
Consider upgrade to RQ^TM rods (e.g. harder threads last longer).	RQ^TM joints have the hardest threads available in the industry.

Box Wear or Box Bulging or Thread Jumping (see Box and Midbody Wear)

CONVENTIONAL AND Q^TM	ROD RQ^TM AND RQ^TMTK ROD
Box bulging due to excessive hoop stresses (see glossary) imposed by thread, potentially from overload. Evident by polished areas on one side of box or thread jumping in the extreme case. Overload may be caused by poor choice of thread compound (see lubrication). Consider upgrade to RQ^TM.	RQ^TMjoints do not bulge nor jump, and have the highest yield strength material available in the industry.
Box wear life exceeded leading to overload. Inspect string for excessive wear. Consider upgrade to RQ^TMlonger.

External Shoulder Wear or External Shoulder Flared / Rolled Over

CONVENTIONAL AND Q^TM	ROD RQ^TM AND RQ^TMTK ROD
Box shoulder flared and/or pin outer shoulder rolled over due to overload. Overload may be due to poor choice of thread compound (see lubrication). Consider upgrading to RQ^TM industry.
Box shoulder wear life exceeded. Inspect stringfor excessive wear. Consider upgrade to RQ^TM rods.	RQ^TMboxes are the hardest available in the industry.

Premature Midbody Wear or High Drillilng Torque

CONVENTIONAL AND Q^TM	ROD RQ^TM AND RQ^TMTK ROD
Hole deviations (e.g. rotary drilled holes, wedging, or down-hole monitoring) induce increased contact pressure and friction between string and hole or casing wall. Improve lubrication of string to compensate.
Hole has oversized or ‘cave’ sections allowing the string to elastically bend or buckle under load increasing contact pressure and friction. Reduce drilling loads or rotation speed to compensate or repair hole.
High pullback or thrust load combined with high rotation speed has caused the string to elastically permanently bend, increasing contact pressure and friction against the hole or casing wall. Evident by polished or heavy wear on one side of string in a slow spiral pattern (e.g. spiral has a multiple length pitch). Reduce drilling loads and/ or pullback. Consider upgrade to RQ^TM rods (e.g. RQ^TM midbodies have double the bend strength).	High pullback or thrust load combined with high rotation speed has caused the string to elastically bend, increasing contact pressure and friction against the hole or casing wall. Evident by polished or heavy wear on one side of string in a ‘slow’ spiral pattern (e.g. spiral has a multiple length pitch).