Fishing Operations (Best Practices)

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S chlu mb er g er P riv ate Schlumberger Schlumberger

CUT & THREAD

FISHING PROCEDURES

AND BEST PRACTICES

Version 2005Jan15

A CUT & THREAD FISHING OPERATION is the most

dangerous operation involving wireline. Prior to starting a cut &

thread operation ensure the following is completed:

A written HARC is completed and discussed with all involved

This “CUT & THREAD” procedure is reviewed with all involved

The operation involves several companies, including the operating

company, the rig company, the fishing hand and Schlumberger. It is an

integrated effort with one supervisor, the Operator Wellsite Supervisor.

Communication is critical for a safe & successful fishing job

EVERYONE INVOLVED IS EMPOWERED TO STOP THE

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S chlu mb er g er P riv ate

Hang Sheave In Derrick

Try to hang sheave with fishing sling so it will not interfere with the handling of drillpipe

Lower sheave must be moved away from rotary to prevent interference with rig floor operations and cable contact with top drive

Clear the rig floor while derrick man hangs the sheave. In order to determine the proper fishing assembly to use,

the derrick man should provide a best estimate of the distance available between the top of pipe and the sheave.

Use Longest Links Available

108” ones are standard; try to use 140” ones or longer Inspect every 5,000’ and before going into open hole for cable wear, damage of fishing equipment, and tightness of fishing equipment

If available, install roller assembly on top drive to eliminate cable rubbing; If one is not available, have rig make one

Do not use the Varco Wireline Adapter commonly known

as “Bicycle Wheels” 108” Top Drive Top Drive >108”

Tension Device

Switch to TDK if using CMTD ( if available) (Prevents cable backlash)

Compare TDK and CMTD readings so that fishing operation is performed under correct tension Do not pre-load lower sheave with air hoist tension; Sheave should hang freely until weight is applied

TDK CMTD Desirable Not Desirable Schlumberger Schlumberger

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Cut the Cable

Pull 1,000 to 2,000 lbs over normal tension and secure T-Bar cable clamp to cable If hole is straight, cut cable 5 to 7 feet above rotary table

If hole is deviated, cut cable 10 feet above rotary table plus 1 foot for every 1,000 feet greater than 10,000 feet

Use proper size cable bushing in T-Bar and

mark cable to ensure there is no slippage

Test T-Bar for slippage before cutting cable

T-Bar Cable

T-Bar

Rig Up Spearhead Overshot

Use tapered cones from LEH-Q on top of fishing weights If available, use heavier-shorter fishing weights with

knuckle joints and swivel, or Wire Rope Weight with Cooper Knuckle-Swivel (a must on top drives!!)

Minimum restrictions for all drilling hardware (jars, drill collars, and heavy weight) must be known to determine size of overshot guide to use

Always use the largest guide that will fit through drilling hardware

Never use “after-market” non-SLB rope sockets. Swivel used to prevent cable torque from backing

off spear assembly.

Or O

r

Cooper Knuckle -Swivel

Knuckle Joints

Overshot Guide

Rig Up Spear

Never use spears which contain “W’s” in their work order numbers

Always use Hexagon Adapter when stripping over;

Hexagon Adapter will stop on top of no-go if dropped

accidentally

Only use plain adapter when drill pipe ID is too small for

Hexagon Adapter and switch back to Hexagon Adapter

as soon as drill pipe ID permits

Hexagon Adapter

Never use “after-market” non- SLB rope sockets

Tapered Cone

Work Order Number Stamped Here

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Hi gh ly Re com m en d ed

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Assemble Overshot

Assemble 4-11/16” overshot, spiral type grapple, and no-go (preferred method) If basket type grapple is used, assemble 5-3/4” overshot, basket grapple, and no-go

ALWAYS VISUALLY INSPECT grapple

for proper size for job and NEVER install a used grapple

4 1

1/16”

5 3/4”

Thread Cable Thru Overshot

Remove hex adapter, pass well end of cable through downhole overshot and reinstall hex adapter (Remember, 2 1/4” hex

adapter will not pass through the smaller ID no-go)

Make-Up Torque

Bowl to Top Sub 5 3/4” 4 11/16” 7600 3200 Bowl to Guide 5 3/4” 4 11/16” 1700 1300 Not Desirable Desirable

Install Drain Sub

Drain sub with blow out disk aids in grapple cleaning and prevents pulling wet drillpipe after disk is blown

Install above downhole overshot assembly

Blow Out Disk

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Thread Through

Slowly ( <2000 FPH) pull overshot assembly to derrick man to thread through bottom hole assembly

Communication is critical at this point to prevent pulling

assembly into the sheave!! Use radios!! Clear rig floor!!

Make sure all minimum restrictions are known in pipe Flag line at winch after bottom of assembly reaches the

the top of pipe. This flag may need to be adjusted in Step 5 when full stands of pipe are used.

DO NOT EXCEED THIS FLAG WITHOUT 1st STOPPING

THE OPERATION, YOU WILL PULL INTO THE SHEAVE!!!

First Stand of Drillpipe, Collars, or Heavy Weight

Remove T-Bar

Tighten overshot to bottom of first stand of drillpipe

Stab spearhead overshot, pull cable tension, check for slippage, and remove T-bar cable clamp after completing check Remove IDW and position spooling arm to one side (If CMTD is used, do not remove)

T-Bar

Tightened Overshot Assembly

Spear Stabbed into Overshot

Cable Tension= 1000 lbs to 2,000 lbs + Normal

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4 When Slips Are Set

After the slips are set, floorhand should position elevators away from spearhead assembly until elevators are clear of assembly. If not done, elevators could catch hex adapter and cause cable to break

Afterwards, install C-plate, slack off cable, and release overshot with special tongs Use correct C-plate for pipe size

C-Plate Location

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3 1/2 IF 4 1/2 IF

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Trip In Slowly

Maintain Proper Cable Tension (1,000 to 2,000 lbs plus normal)

Pay particular attention to top

drive / block; If weights are in danger of hanging up top drive, slack off slightly. but do so carefully. Pull back to 1-2K lbs over once the weights are clear.

Drillpipe

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Flag Line Again

Flag line again at drum and bottom sheave when spear is stabbed in spearhead overshot

ONCE FLAGS ARE SET, DO NOT

EXCEED WITHOUT 1ST

SHUTTING DOWN OPERATIONS AND DISCUSSING WITH ALL !! YOU WILL PULL INTO THE SHEAVE!!

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Flag Line

After tripping in with drill collars, jars, and heavy weights, flag line at drum and bottom sheave with rags, tape, paint, etc... when spearhead overshot is

positioned over drillpipe by the derrick man. Derrick man will thread overshot assembly through drillpipe.

ONCE FLAGS ARE SET, DO NOT

EXCEED WITHOUT 1ST_SHUTTING

DOWN OPERATIONS AND DISCUSSING WITH ALL !!

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Pull overshot to derrick man who will thread through another stand of drillpipe

(watch flag at at drum)

Re-thread Overshot

Stab Overshot

Attach drain sub to second stand of drillpipe Position pipe over spearhead overshot and slack off until “the other flag ” on the drum is reached

Keep hands in safe position

C-Plate Schlumberger

Drillpipe

Make overshot connection, pull enough tension to remove C-plate, and adjust tension again to normal plus 1,000 lbs to 2,000 lbs.

Too low of tension will result in cable being damaged

or completely cut by the overshot assembly as it moves downward. NOW YOU HAVE A CABLE FISHING JOB ON YOUR HANDS!!!!

Make Overshot Connection

C-Plate

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Make-Up Drillpipe

Drillpipe is made-up and tightened Slips are pulled and the descent begins Do not rotate pipe in hole

Observe tension, if it increases stop & discuss

Slips

Tripping in Hole

Repeat procedure for each stand of drillpipe until circulation depth is reached

If excessive open hole is present, circulation every 10 stands (especially if lost circulation material is used) should be considered to keep grapple clean

Remember to watch your speed!!!!

Going in the hole slowly is the only way

If crew changes, STOP… review HARC & Fishing

procedure before proceeding

Trip in Slowly

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Set Slips and Disconnect Overshot

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3

Rethread Overshot Through Drillpipe

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C-Plate

Stab Overshot Make Overshot

Connection

5

Then Make-Up Drill Pipe Remove C-Plate

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Engage Fish

Maintain normal tension plus 1,000 to 2,000 lbs and approach fish slowly;

Observe tension and set at least 2,000 additional pounds on fish; Pull at least 2 joints of drillpipe (60’) and observe tension

A minimum tension loss of 2,000 lbs should be observed to confirm latch (a tension resulting in 0 after pulling pipe would be a definite indication of engagement)

Repeat this engagement procedure at least twice

If tension does not decrease, the fish in not engaged DO NOT ROTATE PIPE AFTER ENGAGING FISH!!!

Install Circulating Sub

Install sub one stand above fish

Never put circulating sub in hole Spearhead Overshot

Circulating Sub

Spearhead Sub

C-Plate

Kelly or Top Drive

Circulating Basket

Circulating Sub

Circulate One Stand Above Fish

Cuttings and debris should be removed from downhole overshot assembly by circulation of mud at a one stand maximum

Only circulate long enough to ensure grapple is clean

Never circulate too long or too fast; cable damage will occur

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Blow Drain Sub Disk

Apply mud pump pressure to blow disk in sub

Pump slug; especially for oil base mud

(Do not trip out with oil base wet string; it’s unsafe)

Afterwards, repeat engagement process before breaking

weak point to make sure tool was not pumped out of the overshot

Blown Disk Drain Sub

Reconfirm Engagement

Repeat engagement process at least twice to ensure tool is still in downhole overshot

Again, observe tension and set at least 2,000 additional pounds on fish;

Pull at least 2 joints of drillpipe (60’) and observe tension A minimum tension loss of 2,000 lbs should be observed to confirm latch (a tension resulting in 0 after pulling pipe would be a definite indication of engagement)

Break Weak Point

Install T-Bar and calculate cable stretch required to break weak point

(Depth) X (Stretch Coefficient)

Move cable up and down within stretch limit with block to work tension to weak point Use block to break weak point and record tension at which break occurs

Make sure rig floor is clear and inspect lower

sheave chain before proceeding

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Install TIW Valve

Install TIW valve before spooling cable onto drum

This could aid in controlling well if trouble occurs

Logging Cable

TIW Valve

Spool Cable

Observe square knot as it goes over upper and lower sheaves

Afterwards, reinstall IDW to measure cable

Do not pull the weakpoint assembly over the

sheave!!

Clear rig floor when near surface Schlumberger

Square Knot

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Tie Square Knot

Cut off rope sockets on both well end and unit end of cable

Tie square knot in cable, pull tight , and tape ends

Square knots reduce cable breaking strength by 50%!! Consult In-Touch on High Tension jobs!!

Don't pull tension on a square knot above 25% of

the cable break strength. In that case use two T-bar method to get the knot to the drum plus at least three wraps before pulling.

To Logging Unit To Well

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Removing Fish

Remove guide and bump tool vertically against rig floor to free grapple control

Spin tool and grapple out of overshot by turning in a clockwise motion

(Tool should come free without applying excessive force)

If another method is used to release tool, remove electronics from housing in overshot to minimize damage

Grapple Control

Guide Shoe

Grapple

Tripping Out of Hole

Do not rotate pipe while tripping out of hole; Rotation may cause fish to disengage and fall out of downhole overshot

DO NOT ROTATE DRILLPIPE!!!

Drillpipe

At Surface

Install make-up plate at first available tool collar and remove overshot assembly Remove remaining toolstring with air hoist, cover hole, and finish breaking and cleaning tools in rat hole

Make sure air hoist is rated for toolstring

Make-up Plate Downhole Overshot

With Fished Tool

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Reverse Cut and Thread

USE THIS TECHNIQUE IF:

a) The weakpoint can not be safely broken due to deviation and doglegs

b) If you want the cable to remain attached to the toolstring until it reaches the casing or surface (normally when fishing with RA sources)

c) If you suspect the rubber boot on the top of bridle is wedged inside the grapple (when fishing with logging bridles) impeccable

12 Method1: Single T-Bar and Reef Knot method

Provides an alternative to breaking the weak point after the tool string has been engaged in the grapple.

- Safest and most reliable fishing technique

- Only one cable clamp is needed

- Cable tension can be continuously monitored. If the fish is pulled out of the

grapple, you can see the tension increase and act promptly.

- The disadvantage is that the procedure is relatively slow and requires a lot of co-ordinatingwith the derrick man.

Method2: Dual T-Bar method

- Not a recommended procedure

- No longer have control over the down hole tension of the cable.

- Need too feed a lot of slack into the pipe.

- Should the fish fall out of the grapple and become stuck, excessive tension may

either strip the cable out of the cable clamp or break the weak point.

- To use this method you must be 100% sure that the tool is properly engaged in the grapple.

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13 Single T-Bar and Reef Knot method

Cut Spear and Overshot

Break the last stand and put a T-Bar on the cable and slack until spear,overshot, and weights are out

Cut off the spear,overshot and weights on both end of cable

Cut

Remove cable from Drill Pipe

Re-attach one weight bar and pull the cable out of the drill pipe with help from derickman.

Lower the cable once it is out of the drill pipe

NOTE:

- Need at least 1 weight bar as counter weight so that cable will not slip from the top sheave

- Better to pull the cable by hand instead of using winch for better control (reduce chances of weight bar knocking the top sheave)

Tie Square Knot

Remove the weight bar from the uphole end of the cable. Tie square knot in cable, pull tight, and tape ends.

NOTE:

Make sure the tails of the knot is long enough and and properly taped to avoid the knot from coming loose.

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14 _{Reversing out}

Pull up with the winch until the knot is tight

NOTE:

Clear the rig floor when picking up the cable. In case the knot unravels, the cable will come out through the upper sheave and fall on the rig floor

Remove the T-Bar and slack down until the knot is inside the drill pipe

Driller will pull up the drillpipe and break the next connection.

Remove cable from Drill Pipe

Have the driller pull up the drill pipe

Pull the wireline cable up 90ft/30m (or depending on the length of the drillpipe connection)

Slack off the cable until the knot is out of the pipe Cut both ends of the cable

Make sure knot is tight

Cut

Continue Reversing out

Re-attach one weight bar and pull the cable out of the drill pipe with help from derickman.

Lower the cable once it is out of the drill pipe Remove the weight bar. Tie a square knot and keep doing this until the bottom of the fish is in the casing shoe or the tool is at surface

You can proceed with breaking the weakpoint by following the previous instructions.

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15 Preparing the T-Bar

Connect slings to the T-Bar handle and attach the sling to the rig air tugger

Have the Driller pick up the drill pipe, and pick up the slack on the air tugger as well along with the drill pipe

Dual T-Bar method

Cut Spear and Overshot

Break the last stand and put a T-Bar on the cable and slack until spear,overshot, and weights are out Cut off the cable on the downhole end.

Release the spear from the overshot using the special thong

Cut

Remove cable from Drill Pipe

Pull the cable out of the drill pipe with help from derickman.

Lower the cable once it is out of the drill pipe

Secure the uphole end of the cable since it will not be used for now

NOTE:

- Better to pull the cable by hand instead of using winch for better control (reduce chances of weight bar knocking the top sheave)

Air Tugger

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16 Pulling Out Pipe

Lower down the top T-Bar using the air tugger Rat back the drill pipe into the derrick

Cut the cable close to the lower T-Bar

Continue doing this until the bottom of the fish is in the casing shoe or the tool is at surface

You can proceed with breaking the weakpoint by following the previous instructions.

Installing 2

nd

_T-Bar

Have the Driller break the connection, and then pick up the drill pipe just enough to install the 2nd_T-Bar

Make sure the air tugger is holding the top T-Bar firmly

NOTE:

Be careful not to pick up too much. If not you can break the weakpoint

Removing Cable from Top T-Bar

Clear the rig floor of all unnecessary personnel Have the derickman slowly loosen up the top T-bar. The cable should slide down from inside the drill pipe If the cable not coming out, the operator needs to pull the cable out by using a long hook. Make sure he is at a safe distance before pulling out the cable.

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When Things Go Wrong

Spearhead Cable Shortens During Descent

If cable cutting length calculations are incorrect at the beginning of the job, the

spearhead will move closer to the rig floor as the downhole overshot approaches the

fish. This can be a real problem with highly deviated and dog-legged wells. During the

descent, cable is pulled off the wall reducing its original length. Normal tension also

increases to keep the spearhead assembly at the same distance above the rig floor. This

is similar to holding a rope and applying a force in the center to cause a deflection. As

the deflection increases, the rope’s length decreases (Fig. 1). When this reaches an

unacceptable level where the C-plate can’t be applied, the operation will come to a halt

(Fig. 2). One option to solve this problem is to install an extension below the

spearhead to increase the distance from the rig floor.

Figure 1

New Length Original Length

Figure 2

Option two involves cutting the cable below the spearhead and adding extra cable by

building two new rope sockets and using a double ended torpedo (Fig. 3). After this

extra length is added, the spearhead is reinstalled and tested.

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When Things Go Wrong Continued…..

Figure 3

There is a slight possibility that too much cable may be added using these options.

When this happens, slacking off on the cable becomes a reality whenever the C-plate is

removed or installed and can cause cable damage if not performed correctly (Fig. 4).

Slacking when the pipe is motionless is fine and should not cause any problems as

long as it is removed and the correct tension regained before the pipe is moved.

Figure 4

Double Ended Torpedo Spearhead Assembly

Rope Socket Housing

Rope Socket Housing Extension

Spearhead Assembly

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