Running & Landing Casing Casing Design Workshop

Chapter 8 Outline Handling Casing Transport to Location On Location Communicate Design to Rig Supervisor Pipe Measurements

Outline Cont. Running Casing Getting Pipe to Rig Floor Stabbing Filling Casing Makeup Torque Thread Locking Casing Handling Tools Getting Casing to Bottom Crossover Joints

Outline Cont. Landing Practices Wellhead Equipment for Casing Freeze Point Maximum Hanging Weight Wellhead Equipment for Casing

Video Links for Cementing Casing & Centralizers https://www.youtube.com/watch?v=7Er7LhSBeKs Cementing Offshore Drilling https://www.youtube.com/watch?v=Cn64fLc-KEE Casing Centralizer Placement

Video Link for Running Casing https://www.youtube.com/watch?v=OXgUKXFsJ_I Running Casing Animation

Transport to Location Prevent damage Loading and unloading sequence Thread protectors Stripping Secured with straps Protection from environment Unloading procedures Stripping on pipe racks Loading and unloading sequence Get it correct

On Location Minimum movement or relocation Drift for internal diameter & obstructions Remove thread protectors and clean threads and protectors Visually inspect threads Lubricate threads with proper lubricant (especially offshore) Reinstall protectors (depending on handling facilities and methods) Do not set equipment on casing on pipe racks

Moving Casing to Rig Floor Use safe handling methods If thread protectors not reinstalled Use rubber clamp-on protectors on pin Do not use hooks in pipe ends Do not allow casing to slide out of V-door Pin must be protected at all times

Pipe Measurements Who is responsible for accurate casing measurements Company representative ! Always! Not the responsibility of the rig crew ! Joints should be numbered (paint marker) Talley book should be orderly, neat, and systematic so errors are easily spotted Double check the addition ! Chalk numbers wash off or rub off

Cross-over Joints Check all cross-over joints Correct threads Measure and mark with identification Proprietary threads cut by licensed machine shop or manufacturer Check the grade of the tube Isolate to separate area or place in string in proper position Always have redundant cross-over joints on location

ST&C to LT&C ST&C pin will make up in LT&C coupling LT&C pin will not make up into an ST&C coupling Use a dedicated cross-over joint LT&C coupling as a cross-over ? Avoid if possible ST&C coupling often difficult to remove May damage pin when removing ST&C coupling Fortunately most casing sizes and types are now made in either ST&C or LT&C so this is not a common problem. But it still occurs occasionally. LT&C coupling as a cross-over has been common practice for many years, but is a bad practice unless it installed at a pipe facility with proper equipment. Never wait until it is the next joint in the running process as delays or damage could jeopardize getting the string to bottom.

Stabbing Casing Stabbing board Stabbing arm Stable Properly positioned Stabbing arm Guide on bottom of elevator to prevent damage Wind can cause stabbing problems Do not rush the stabbing procedure Some proprietary connections require stabbing guides

Filling Casing Fill casing as it is run Verify fill visually Large diameter pipe requires large capacity fill line Self-fill and differential-fill float equipment Can allow cuttings and other objects in casing and plug float equipment Avoid when possible, and never use in unconsolidated formation environments A plugged float is a disaster in cementing. If it occurs prior to cementing, significant measures in both time and expense will be required (including possibly perforating the casing to place the cement and holding pressure on the casing while the cement sets). If it plugs while cementing, the cement job is over. Remaining cement will have to be drilled out and possibly the casing will have to be perforated to perform additional cementing. Avoiding circulating out large volumes of air is worth the time to fill the pipe, especially if you will properly size the line working with the rig contractor. Well control incidents have occurred from circulating out air pockets improperly. JEB

Make-up Torque Determine proper makeup torque for connections Rig casing tong line at 90°to tong arm for proper torque reading Use only approved thread lubricants on clean threads Proper number of turns can also be measured

Thread Lubricant Apply to box, not pin Do not use DP or DC dope Standard is API Modified Proprietary threads – check manufacturer Environmental Considerations Special formulations available Some threads specially coated for self lube Friction factor – specified relative to API Mod, adjust make-up torque accordingly Always check manufacturer’s recommendations on lubricant and torque for proprietary connection

Thread Locking Prevents back-off of lower joints during drill-out of float equipment Polymer compound Used on bottom joints & float equipment Inexpensive and easy to use Lock mill end of connections? In the event casing has to be pulled before reaching bottom? Welding? (never on N80 or higher grade!) Relying on mill end of connection to not back off is chancy. Better to thread lock mill end too – best done at a pipe facility beforehand. Do not be concerned about the old rule of thumb, “Do not thread lock anything longer than can be stood back in the derrick.” If you have To pull casing back out of the hole thread locked joints is the least of your problems (use heat to break down the polymer).

Casing Handling Tools Spider Elevator Sets on rig floor Slip type (integral or manual removable) Wrap-around (must open for each joint) Elevator Attached to traveling block bails Slip type (always integral) Wrap-around type (must open for each joint)

For first few joints only ! Manual Casing Slips This is crucial to avoid a fishing job for a few joints of casing. JEB For first few joints only !

Wrap-around Spider

Wrap-around Spider

500 Ton Elevator

1000 Ton Elevator

More Elevators Internal Grip 350 ton

1000 Ton Spider

Compact Spiders Fit into rotary table bowl (with rotary drive bushing removed).

Compact Spider

Precautions High capacity tools open very easily with light casing load Care must be taken to prevent accidental opening Some air systems prevent opening if the other component is already open Good practice: start string in hole with low capacity tools switch to high capacity once there is sufficient casing weight to prevent accidental opening The casing seat before going into open-hole is often used as a place to swap out low-capacity for high-capacity equipment. JEB

Getting to Bottom If casing stops before reaching bottom Circulate? Will that cause differential sticking? Pull out and lay down casing? Thread damage when pulling out? Locked threads? Have a contingency plan before starting in hole If casing stops close to bottom ? check pipe measurements If you’re 40’ or 80’ off-bottom, you likely are off on your joint count. Check the location thoroughly. JEB

Highly Deviated Wells Pipe beyond a critical inclination point (70°) must be pushed in hole Friction calculations are essential before running pipe Hook load decreases as casing nears bottom crit  70 force required This also appears in cased-hole sections along with open-hole. Cuttings can accumulate in the cased hole portions between 45-70 degrees. JEB

Reducing Friction Increase Lubricity (reduce m ) Oil muds Special additives Plastic beads Calcium carbonate Graphite Etc. Reduce Contact Force (reduce N ) Lighter casing below critical angle Good centralizers Float portion of casing (ERD wells)

Pressure Containment Annular BOP Install proper size rams Test rams ! OK for some very low pressure applications Not sufficient for most applications Install proper size rams Test rams !

BOP Rams Must Fit Casing ! This was one of the first oil-field photos to “go viral”. You don’t want to have the incident that gets global “viral” attention. JEB

Landing Practices (Slip-type Hangers) How much string weight should be applied to casing hanger? No standard practice Probably as many practices as there are companies Considerations: Prevent buckling above freeze point to reduce casing wear Prevent buckling in un-cemented areas; can cause failure

Freeze Point ? A point at which the pipe is fixed down hole Usually taken to be the top of cement Actual freeze point is never known

Neutral Point ? The point at which the “effective” axial load goes from tension to compression Not known, can be estimated from calculations This is not the same point as the neutral point as defined on the true axial loads which has no meaning for buckling

Common Landing Practices Same load on hanger as hook load Tension in all casing above freeze point Neutral point at the freeze point Some percentage of hook load on hanger (e.g. 80%, 75% etc.) Why? Hanging weight sometimes reduced to avoid too much compression load on top of conductor/surface pipe. No choices for mandrel type hangers

Slip Type Hangers

Maximum Hanging Weight Weight of the casing on slip type hangers causes radial compressive stress on the casing: verify that the hanging weight will not cause the casing to collapse. Longer slip elements may be necessary

Maximum Hanging Weight Safety factor? 2.0? Taper of slip segment is measured from vertical Compare result to the biaxial collapse rating of the casing See example in Chapter 8 One company using this formula specifies a safety factor of 2

Example (Chapter 8) From our continuing example the 7” production casing has the following data: Buoyed casing string weight at surface: 340,000 lb Type of 7” casing at surface: 29 lb/ft, P-110, Collapse rating: 7625 psi Hanger taper: 25° Hanger slip length: 10 in. Using a safety factor of 2.0, determine if the entire buoyed weight of the string can be hung on a hanger The biaxial collapse rating of the casing with 340,000 lb tension is calculated from the formulas of the previous chapter and is: 8090 psi Well below the reduced collapse value of 8090 psi with a safety factor of 2.0

Wellhead Equipment Casing Heads Casing Spools Casing Hangers Slip-on Weld Threaded Casing Spools Casing Hangers Slip type Mandrel type Precautions

Video Clip on Wellhead Equipment https://www.youtube.com/watch?v=khqqMzbg8xk&list=PLViEMM m4R8k6BC5YjWvEw9tHbivtMS5MD&index=19 Well Completion : Casing Head Optional: https://www.youtube.com/watch?v=z9eWHpEDRME Wellhead instillation.wmv

Casing Head – Slip-on Weld Conductor is cut off, surface casing is cut off and head welded to surface casing Most popular Requires cutting & welding May include a base plate to weld to conductor instead of surface casing

Casing Head - Threaded Landing joint & coupling removed and head threaded onto pipe Coupling spacing critical Coupling removal problems Requires cement to surface Possible slumping problem with poor cement

Casing Spool For additional strings of casing Spool body pressure rating and lower flange are compatible to the casing string below the spool Upper flange is rated to be compatible with casing string that will hang in the spool

Casing Hanger – Slip Type Installed on casing above head and slipped into bowl Often requires BOP removal Allows adjustment of hanging tension Requires cutting casing

Dangers of Slip Type Hangers Removal of BOP to install hanger/pack-off or to weld hanger is always a hazardous operation because of potential gas migration.

Casing Hanger – Mandrel Type Threads onto casing and landing joint and lowered into head prior to cementing Simple, no moving parts Cannot adjust landing tension Reciprocate during cementing? NO! One-piece types (surface applications only) Circulate cementing returns through casing head side outlet Fluted types (subsea applications) Pack-off and locking device must be installed before hanger is in safe mode

Two-Piece Mandrel Type Attached to casing Run on landing joint w/run tool Usually fluted with separate pack-off for cementing Mandrel type (fluted) is only choice for subsea

Precautions Valves required on side outlets Pressure gage required on each head or spool Maximum service pressure (MSP) and test pressure Never use the test pressure for selection Use only MSP in selection

Running and Landing Practices Running casing is intense and non-stop Correct measurements are crucial Install and test proper BOP rams Assume that operations cannot stop once begun Everything ready and functioning before start Have contingency plans Precautions for slip-type hangers Set hanger without removing BOP if possible Allow adequate cement setting time before removing BOP Check for any flow before removing BOP Never assume a slight flow is heat expansion