logging while fishing

Schlumberger Wireline & Testing

Nisku Special Services

Logging While FishingLogging While Fishing

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LWF*

Logging While Fishing is a method which combines drillpipe conveyed logging (TLC*)with cut and thread fishing.

LWF provides means for retrieving a stuck wireline logging tool and completingthe logging run during the same pipe descent.

* Mark of Schlumberger

TOOL COMPATIBILITY:LWF is compatible with all Schlumberger telemetry tools except RFT. LWF is especially well suited to MDT and seismic operations.

CREW & EQUIPMENT:The LWF crew consists of one or two LWF/TLC specialists. LWF equipment can be mobilized independently, or more commonly, LWF equipment can be combined with and mobilized with TLC equipment since LWF jobs are often followed by TLC logging.

DRILLPIPE CONNECTIONS:LWF subs have 4 1/2 IF or 3 1/2 IF threads.The LWF specialist will arrange for rental of any cross overs that may be needed.

CASING SIZE LIMITATION:A minimum of 0.25” clearance is needed for the Cable Side Entry Sub (CSES) to enter surface casing. Less than 0.25” clearance may result in cable damage.The 4 1/2 IF CSES requires surface casing drift ID of 7” or greater.The 3 1/2 IF CSES requires surface casing drift ID of 6” or greater.

OPERATIONAL NOTES :1. The Cable Side Entry Sub (CSES) should never go into open hole. The probability of cable damage is greatly increased when a CSES is run into open hole. Therefore, the amount of open hole that can be logged with LWF is limited to the amount of casing in the hole (e.g. if casing depth is 4000 feet, a maximum of 4000 feet of open hole can be logged by LWF). This point needs to be considered for wells with more open hole than casing .

2. For most wells, the Cable Side Entry Sub (CSES) and Cable Cutter Sub (CCTS) are installed when the tool overshot is inside casing, near the shoe. However, for wells with more open hole than casing it may be necessary to install the CSES and CCTS when drillpipe is in open hole. This condition arises when the drillpipe needs to go twice casing depth to either retrieve a stuck tool or LWF a deeper zone of interest. The process of installing the CSES/CCTS and converting from cut-and-thread to LWF takes about 30 minutes, and duringthis time it may not be possible to move drillpipe. To avoid sticking drillpipe, this needs to be considered when planning the LWF job.

3. During the cut-and-thread phase of the job, 1000 lbs over normal cable weight is maintained on the wireline as drillpipe is threaded into the hole . When holding this tension, the wireline overshot & weight assembly will be about 15-30 feet above the drillfloor. The wireline overshot & weight assembly will not pass cleanly around a top drive as the block approaches the drillfloor. Therefore, onrigs with top drives it is necessary to keep the wireline overshot & weight assembly below the top drive as drillpipe is threaded into thehole. This is best accomplished by running a “double” while holding 1000 lbs over normal cable weight. Then stop the drillpipe and lower the wireline overshot & weight assembly to a safe position which provides clearance for the top drive when setting drillpipe in the slips. This “safe position” should be wireline flagged for the driller to see. When the driller sees the flag indicating overshot & weights are in the “safe position”, the top joint of drillpipe can then be run in hole, and the slips set. Radio communication between driller and winch operator should be maintained during this phase. In addition, the winch operator should have a clear view of the drillfloor if possible. It is also advised that long bales be used during the cut and thread phase. If the wireline overshot & weight assemblyhappens to be located above the “safe position”, the weight bars will exit the top of the drillpipe as the top joint is run in hole. Long bales are recommended to provide a clearer view of the weight bars should they exit the top of drillpipe, and possibly provide enough reaction time for the driller to stop the block before the weight bars are hit by the top drive.

4. Schlumberger logging tools have compressive load limits ranging from 23000 lbs to 1500 lbs. Tool compression may occur when the toolstring is being engaged by the overshot, and if additional logging is required below the stuck depth, compression may occuras the tool is being pushed downhole by drillpipe. If an ACTS or AMS exists in the logging toolstring, the logging engineer can accuratelymonitor tool compression in the logging unit, and radio this information to the drillfloor as the tool is being engaged by the overshot or asthe logging tools are being pushed downhole. The driller, receiving compression information from the logging engineer, will know when to stop drillpipe if an obstruction is hit. If the stuck toolstring does not include an ACTS or AMS, the Martin Decker gauge will be the only source of compression information. When this condition exists, and if the toolstring is to be pushed below the stuck depth, the LWF specialist will provide advise concerning the compressive load limit and the risk of pushing the tools downhole.

5. Good communication is essential for a safe and efficient LWF operation. The LWF specialist on location will conduct a pre-job meetingto cover safety issues and explain the LWF procedure to all persons involved in the job.

Schlumberger LWF EquipmentSchlumberger LWF Equipment

Cable Side Entry Sub

Cable Cutter Sub

CSES SPECIFIC ATIONS

GENERAL FEATURES Rubber packing assembly seals around wireline.Ball check valve provides pressure seal if wireline is removed from drillpipe.CSES sizes currently available : 4 1/2 IF, 3 1/2 IF, 2 7/8 EUE

Wear

Ball checkvalve

Packing assembly

bushing

Wearbushing

Shearbolt

Slidingmandrel

Cutterblade

4 1/2 IF 3 1/2 IF 2 7/8 EUE

1.88

Packing assembly pressure rating

Maximum tensile load (SF=1.5)

Maximum OD (w/ clamp)

Minimum ID (inches)

6.62 in. 5.88 in. 4.6 in.

3000 psi 3000 psi 3000 psi

Make-up length 2.0 ft 3.29 ft

GENERAL FEATURESCCTS provides means for removal of wireline from stuck drillpipe.The cable cutter is actuated when the weakpoint housing engages the wear bushing and 3600 lbs overpull is applied to the shear bolt. The shear bolt shears, allowing the sliding mandrel to move. As the sliding mandrel is pulled upward, it forces the cutter blade into the path of the wireline and the wireline is cut.After wireline is cut, the weakpoint housing falls back down to the logging tool (still in grapple), and the sliding mandrel and cutter blade return to the original full-open position providing clearance for free-point backoff tools.CCTS sizes currently available : 4 1/2 IF, 3 1/2 IF

CCTS SPECIFICATIONS

Minimum ID

500,000 lbs 350,000 lbs 174,000 lbs

2.16 ft

1.88 1.0

wear bushing *

Make-up length 46.5” 45.5”

Maximum tensile load (SF=1.5) 565,000 lbs 326,000 lbs

Maximum OD 6.61 in. 5.5 in.

wear bushing *

4 1/2 IF 3 1/2 IF

* wear bushing sizes : 1 1/4”, 1 1/2”, 1 7/8”page 2

Wireline

Weakpoint housing

Maximum Compression (SF=1.5) 626,000 lbs 432,500 lbs 253,500 lbs

LWF LOGGING SYSTEMLWF LOGGING SYSTEM

Schlumberger

Scenario #1

1. Wireline logging tools stuck in openhole during up-log.2. Good log has been obtained from TD up to stuck depth.

Objective : Up-log from stuck depth to casing.

Scenario #2

1. Wireline logging tools stuck in openhole during down-log.2. TD was not reached.

Objective : Push logging tools to TD.

stuck

Two typical LWF scenarios

ORTake station measurements (e.g. MDT)from stuck depth to casing.

logging tool

THENUp-log from TD to casing.

ORTake station measurements (e.g. MDT)from TD to casing.

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Schlumberger

Prepare for cut & thread :

1. Pull 2000 lbs over normal cable weight.2. T-bar the wireline.3. Cut wireline 10-15 ft above T-bar.4. Hang upper sheave from derrick.5. Switch from CMTD to TDK (for spooling double-end torpedo).6. Build rope sockets on both ends of wireline.7. Make up spear, overshot & weight assembly to wireline.

Cut & thread :

Cut & thread drillpipe until tool overshot reaches pre-determined depth.Winch operator holds 1000 lbs over normal cable weight as drillpipe moves downward.

Cut & Thread procedure

overshot & weightsspear

stuck logging

The Logging While Fishing operation begins as a normal cut and thread operation.The wireline is cut and drillpipe is threaded down to some pre-determined depth (usually to the casing shoe).

tool

Toolovershot

Note : Since the wireline is initially cut at 15’, this will put the wireline overshot & weight assembly at 15-30’ above the drillfloor when holding 1000 lbs over normal cable weight. When threading drillpipe in hole, if the overshot & weight assembly snag upon the block, broken wireline could result. Care must be taken as the block moves past the overshot & weight assembly.

On rigs with top drives, the overshot & weight assembly will not pass around the top drive as the block is lowered. With top drives it is necessary to modify the cut and thread technique slightly. (See “Operational Notes”, Note No. 3)

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wireline


Converting to Logging While Fishing

Tool overshot has reached appropriate depth.*** Cut & Thread phase completed ***

Converting to LWF involves replacing the wireline fishing assembly (spear, overshot and weights) with the LWF double-end torpedo, reconnecting the wireline conductors, and installing the CCTS & CSES.

Procedure1. Pull 2000 lbs over normal cable weight.2. T-bar the cable.3. Remove wireline overshot, spear and weights from cable.4. Thread downhole end of cable through CCTS and CSES.5. Reconnect uphole and downhole conductors at rope sockets.6. Logging engineer verifies tool operation (power up logging tools).7. Secure rope sockets and conductor wires in double-end torpedo.8. Install CSES packing assembly.9. Winch operator pulls cable tension until T-bar rises off drillpipe.10. Remove T-bar from cable.11. Drillcrew makes up CCTS/CSES to drillpipe in slips.12. Make up stand of drillpipe above CCTS/CSES.

Wireline (uphole end)

to upper sheave wheel

Double-end torpedo

Rope socket &7 conductor wires

Rope socket &7 conductor wires

Wireline(downhole end)

Cable Cutter Sub Cable Side Entry Sub

(CCTS) (CSES)

T-bar

C-plate

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Schlumberger

double-end torpedo

CSES

CCTS

stuck logging tool

wireline

Logging While Fishing

The wireline is reconnected and secured in the double-end torpedo.The CCTS and CSES are made up.The logging tools are working.

Ready to RIH with drillpipe to catch the fish.

Tool overshot& grapple

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Schlumberger

double-end torpedo

CSES

CCTS

logging tool in grapple

wireline

No cable movement(holding tension)


snatch block

Drillpipemovement

Catching the Fish

Procedure1. Snatch block is installed on wireline (makes room for tongs).2. Winch operator holds 1000 lbs over normal cable weight.3. Driller runs in hole with drillpipe. Note : Wireline is not clamped at the CSES during the LWF operation. Wireline slips through CSES as drillpipe moves down.4. Logging tools engaged by grapple.

Pumping Capability :

The CSES packing assembly seals around the wireline, thus enabling pumping at any time (e.g. to clean out grapple prior to engaging fish) providing continuous well control.

Pumping Capability :

The CSES packing assembly seals around the wireline, thus enabling pumping at any time (e.g. to clean out grapple prior to engaging fish) providing continuous well control.

Additional LWF benefit :

If the logging toolstring includes an ACTS or AMS, the logging engineer can monitor tool compression to verifythe grapple has engaged the stuck logging tools.

Additional LWF benefit :

If the logging toolstring includes an ACTS or AMS, the logging engineer can monitor tool compression to verifythe grapple has engaged the stuck logging tools.

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Schlumberger

double-end torpedo

CSES

CCTS


drillpipe

wireline

Drillpipemovement

Cablemovement


Scenario #1 : Up-log from stuck depth back to casing.

Procedure1. Winch operator pulls 1000 lbs over normal cable weight.2. Driller pulls drillpipe at logging speed, stopping at station depths as needed.3. Winch operator spools wireline back onto cable drum, maintaining 1000 lbs over normal cable weight as drillpipe is pulled. Double-end torpedo spools back onto cable drum.

Log data is obtained as drillpipe and tools move uphole.

Acquiring Log Data

With the logging tools engaged in the grapple it is then possibleto complete the logging operation as the drillpipe is moved either up or down.

Log data can be obtained either continuously or at stations.

Continuous : Log data obtained as drillpipe moves uphole.(Traditional openhole logs)

Stations : Drillpipe is momentarily stopped in openhole for pressure readings, fluid sampling or seismic acquisition.

Retrieving Logging Tools to the surface

OR Take station measurements (e.g. MDT) from stuck depth back to casing.

Procedure*** after CSES and CCTS have returned to the drillfloor ***1. Pull wireline to break weakpoint at logging head.2. Pull wireline until weakpoint housing is near surface (about 200 ft).3. Break out CSES /CCTS and hoist them above the drillfloor.4. Pull remaining 200’ of wireline out of drillpipe.5. Trip out of hole with drillpipe (logging tools in grapple).

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Schlumberger


CSES

CCTS

drillpipe

wireline

double-end torpedo

Cablemovement

Drillpipemovement


Scenario #2 : Push logging tools to TD.

ProcedurePushing logging tools to TD :1. With the logging tools in the grapple, the driller begins pushing the tools downhole. Cable is spooled off the cable drum as drillpipe moves down. Double-ended torpedo goes below the rotary table. Winch operator maintains 1000 lbs over normal cable weight. As logging tools move downhole, logging engineer monitors tool compression if ACTS or AMS is included in toolstring.2. If log to maximum depth is desired, run tools to within 5-10 ft of TD. Tagging bottom is not recommended since tool damage may result.

Logging from TD back to casing :1. Winch operator pulls 1000 lbs over normal cable weight.2. Driller pulls drillpipe at logging speed, stopping at station depths as needed.3. Winch operator spools wireline back onto drum, maintaining 1000 lbs over normal cable weight as drillpipe moves up.4. Double-ended torpedo passes rotary table and is spooled back onto cable drum.

Log data is obtained as drillpipe and logging tools move uphole.

Acquiring Log Data - cont’d

THENUp-log from TD to casing.

ORTake station measurements (e.g. MDT) from TD back to casing.

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Schlumberger


CSES

CCTS

drillpipe

wireline

Pulling the weak point CCTS cuts the wireline

Purpose of the Cable Cutter Sub :

If drillpipe becomes stuck during LWF, the CCTS provides means for removal of wireline from the drillpipe.

Procedure 1. Pull wireline to break weakpoint at logging head. 2. Begin pulling wireline out of hole. 3. Weakpoint housing engages CCTS / cutter blade cuts the wireline. 4. Severed cable end passes through CSES into the annulus. 5. Weakpoint housing falls back down to logging tool in grapple. 6. Pull wireline out of hole.

Procedure 1. Pull wireline to break weakpoint at logging head. 2. Begin pulling wireline out of hole. 3. Weakpoint housing engages CCTS / cutter blade cuts the wireline. 4. Severed cable end passes through CSES into the annulus. 5. Weakpoint housing falls back down to logging tool in grapple. 6. Pull wireline out of hole.

double-endtorpedo

Removal of wireline from stuck drillpipe :

weakpoint

weakpoint housing

weakpointhousing

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logging while fishing

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