best practices day one new morning
TRANSCRIPT
8-3-2000 1
8-3-2000 2
Introduction
• Share my experiences
• Learn from each other
• Understand tools/ applications
• Match tools/ application to needs
8-3-2000 3
Agenda
• Job planning/ record keeping
• Fishing for Junk
• Procedures to part pipe
• Open hole fishing
• Fishing in cavities
• Drilling fluids
• Fishing for parted pipe
• Cased hole fishing
• Jarring operations
• Fishing in laterals
• Casing repair
• Wireline fishing
8-3-2000 4
What is Fishing
• Fishing is the technology of removing any
undesirable object from the wellbore.
• It is an evolving thought process driven by
changing conditions.
• Keenness of insight tempered by experience is
required to avoid running out of options.
8-3-2000 5
Formula for success
• Mentor
• Visualization skills
• Communication skills
• Enjoy what you do
8-3-2000 6
W.I.I.F.M.
• Pride of achievement
• Develop customer base
• Increase job security
• Pay raises/Promotion/Travel
8-3-2000 7
Getting to know you
• Live in Friendswood, Texas
• Oilfield 42 years , 34/fishing
• Born in Texas
• Five year old grandson
8-3-2000 8
Quiz
• Gain knowledge; training needs
• Another at the end of classes
• All questions will be discussed
• Take one idea home
8-3-2000 9
Today’s Agenda
• Job planning; Record Keeping
• Fishing for Junk
• Pipe recovery methods
• Open hole fishing
8-3-2000 10
8-3-2000 11
Job Planning/ Record Keeping
• Half the job is in preparation.
• Do your homework thoroughly.
• Formulate a game plan.
• Get consensus;Co. man/ coordinator.
• Think of an alternate plan
8-3-2000 12
Cardinal Rules of Fishing
1. Know your dimensions:
• O.D., I.D., length of fish.
• O.D., I.D., length of fishing assembly.
• O.D., I.D., length of the work string.
• Know where the top of the fish is.
8-3-2000 13
2. Know all tensile and torsional
3. Never rotate the fish out of the hole.
4. Fast trip time is not always the best.
5. Must be OD fishable.
Cardinal Rules of Fishing
8-3-2000 14
6. Familiarize yourself with the fish.
• Make use of the composite catalog
• Technical manuals
• Manufacturers drawings
• Have an exact replica of the fish
Cardinal Rules of Fishing
8-3-2000 15
Maximum O.D. of Tools That Can be Washed Over
Casing Size Maximum Wash Pipe to Cover
O.D. I.D. Wt. O.D. O.D. I.D. Wt.
4-1/2 3.754 16.60 2-3/4 3-1/2 2.955 9.20
4-1/2 3.920 13.50 3-1/16 3-3/4 3.250 9.50
5 4.276 18.00 3-1/4 4 3.428 11.60
5-1/2 4.670 23.00 3-1/2 4-3/8 3.749 13.58
5-1/2 4.778 20.00 3-5/8 4-1/2 3.826 16.60
6 5.240 23.00 4-1/8 5 4.276 18.00
6-5/8 5.791 28.00 4-5/8 5-1/2 4.892 17.00
7 6.004 35.00 4-3/4 5-3/4 4.990 22.50
7 6.276 26.00 5-1/8 6 5.325 20.00
8-3-2000 16
7-5.8 6.625 39.00 5-3/8 6-3/8 5.625 24.00
8-5/8 7.511 49.00 6 7 6.276 26.00
8-5/8 7.825 36.00 6-3/8 7-3/8 6.625 29.00
8-5/8 8.017 28.00 6-5/8 7-5/8 6.875 29.70
9-5/8 8.535 53.50 6-7/8 8-1/8 7.185 39.50
9-5/8 8.835 40.00 7-3/8 8-3/8 7.625 35.00
10-3/4 9.760 55.50 7-7/8 9 8.150 40.00
10-3/4 9.950 45.50 8-3/8 9-5/8 8.681 47.00
13-3/8 All WTS. 10-5/8 11=3/4 10.88 54.00
16 All WTS. 12 13=38 12.415 68.00
Minimum Size Casing Maximum Tools to Run Wash Pipe to Cover With
8-3-2000 17
• Hole
• Casing
• Fish & work string
• Jars
• Operations at time of incident
Important Details
8-3-2000 18
Arriving on Location
• Introduce yourself to Co. man
• Verify all pertinate information
• Record BHA/ pipe in hole/driller
• Count all work string on location
8-3-2000 19
• Tie off any pipe in derrick
• Clean out V door, mark first joint
• On first trip out, strap out of hole
• Verify pipe count/ top of the fish
Arriving on Location
8-3-2000 20
Accurate Top of Fish
• Stay with these numbers
• Use In/out method, check mistakes
• Ask Drillers to notify you if they pick up
or lay down any pipe
8-3-2000 21
In and Out MethodOut In
D.O.K. 23.65 Shoe 4.60
B.H.A. 311.35 3 Jts. WP 95.96
1Std. D.P. 94.00 Sfty. Jt. 2.75
Total out 429.00 Jars 6.90
Total In 411.66 X-over 1.45
Diff. &Dok 17.34 Tools 111.66
10 D.C. 300.00
B.H.A. 411.66
19 Std. DP 1786.00
2197.66
D.O.K. 17.34
T.O.F. 2215.00
8-3-2000 22
In and Out Method
• To change from overshot to washpipe string
• Tally length of string, plus kelly to TOF
• Compute laid out length including DOK
• Subtract picked up from laid down
• The difference is DOK with new string
• Total out must exceed total up to use this
formula.
8-3-2000 23
Calculate Top of Fish Example
• Twisted off while drilling @ 4,000
• Recovered 3,895.73 including DOK
• Made Bit trip; tag fish with 37 DOK
• Subtract the (in) from the (out)
• Difference will be length DOK
8-3-2000 24
Out = kelly+fish
Bit sub& bit 4.45
Jars & subs 39.28
4 D.C. 123.54
D.O.K. 37.00
Total out 204.27
Total in 180.31
D.O.K. 23.96
In = Fishing String
Tools 24.48
5 D.C. 155.83
180.31
In-Out Method
8-3-2000 25
K.B. Measurements
• The Standard Oilfield Measurement to any
depth down hole is recorded from ground
level, plus the distance to the kelly
bushing[KB] on the rig that drilled the
well.
• This is called the original elevation and is
recorded in the well file.
• If a workover rig is later employed , the
difference in this rigs elevation from the
original one must be accounted for.
8-3-2000 26
• The difference in elevation is added to
or subtracted from the current pipe
tally in order to correlate with the
original well elevation.
• This can be of great importance in
some cases.
KB Measurements
8-3-2000 27
• Example: Original elevation is 30.
• Current elevation is 6.
• The difference of 24 must be added to
the current pipe tally so that
downhole depths will correlate.
KB Measurements
8-3-2000 28
Official Well Depth
Official well depth = hole depth plus
elevation
Where:
• hole depth = ground level to TD
• elevation = ground level to KB [on the
rig that drilled the well]
8-3-2000 29
Tally Book Rules
• Accurate, legible & current
• Time, date, trip/ job number
• Brief description/each trip
• Any accidents should be recorded
• As if to pass on to relief man
• Keep book for future reference
8-3-2000 30
Well Data
• Last casing: 8-5/8 x 28# @ 5611
• 7-7/8” HOLE: T D @ 9557’
• Bit stuck 74’ off bottom @ 9483’
• Angle of hole = 35%
• Wt.9.8#; Vis. 36 = WL= 20 YP = 10
8-3-2000 31
Fish in Hole
1. 7-7/8 Rock Bit with 4-1/2 Reg. Pin .70
2. Mud Motor x 6-1/2” x 2-7/8 x 4-1/2 Reg. double box 20.50
3. 4-1/2 X.H. box x 4-1/2 Reg. Pin sub 1.89
4. Pony drill collar x 6-1/4 x 3.oo x 4-1/2 X.H. 10.63
5. 6-1/4 x 7-7/8 stabilizer x 4-1/2 X.H. x 2-3/8 I.D. F.N.=1.10 4.55
6. Float Subx 6-1/4 x 2-3/8 I.D. 2.23
7. M/S subx 6-1/4 x 2-3/8 x 4-1/2 X.H. 2.65
8. M.W.D. x 6-1/2 x 2-7/8 x 4-1/2 X.H. 31.10
9. Monel drill collar x 6-1/2 x 2-1/2 x 4-1/2 X.H. 30.70
10. 9 x drill collars x 6-1/4 2-3/4 x 4-1/2 X.H. 272.08
378.92
8-3-2000 32
Example:Tally Book
5-3/4 od x 4-13/16 id: bu = 5.90 serial # w 8925 5-3/4 bos w/2-7/8 bas.Grap.& mcpo: 2.75
5-3/4 od x 4-3/4 id serial # w 2435 5-3/4 bos extension 3.10
FN .85 x 4-3/4 x 2-3/8 id serial # w 8925 3-1/2 if top sub x 5-3/4 os 1.10
4-3/4 od x 2 id serial # B 1461 4-3/4 bbj x 3-1/2 if conn. 9.90
4-3/4 x 3-1/8 id serial # B 124 4-3/4 boj x 3-1/2 if conn. 10.75
4-3/4 x 2-3/8 id rig Six x 4-3/4 drill collars x 3-1/2 if conn. 184.90
4-5/8 x 2-7/16 id serial # w 222 2-7/8 x 8rd. box x 3-1/2 if pin sub 1.50
BHA 214.00
rig 180 joints 2-7/8 x 8rd tubing 5625.00
5839.00
Down on single 11.00
TOF 5950.00
Trip# 1 @ 2:00 pm 2-4-98 Union Oil
8-3-2000 33
Oilfield abbreviations
R.P.M. - rounds per minute T.O.F. - top of fish
S.P.M. - strokes per minute M.D. - measured depth
W.O.B. - weight on bit T.V.D. - true vertical depth
B.H.A. - bottom hole assembly B.F. - buoyancy factor
W.O.C. - wait on cement D.P. - drill pipe
W.O.O. - wait on orders D.C. - drill collar
W.O.W. - wait on weather D.h - diameter of hole in inches
T.I.H. - trip in hole e - stretch in inches
P.O.H. - pull out hole P - over pull in pounds
G.L.M. - gallons per minute E.S.P. - estimated stuck point
A - annular velocity M.O.P. - margin of over pull
E.C.D. - equivalent circulation density N.P. - neutral point
F.V. - funnel viscosity O.P.T. - optimum
C.&C. - circulate and condition mud M.W. - mud weight in ppg
H.H.P. - hydraulic horsepower Lbs. - pounds
L.C. - loss circulation Len. - length in feet
L.C.D. - loss circulation material L.O.T. - leak off test
Y.P. - yield point B.O.P. - blow out preventor
W.L. - water loss S.L.M. - steel line measurement or strap in/out hole
8-3-2000 34
Window Milling
Depth R.P.M. S.P.M. W.O.B. Torque Time Minutes Feet
3284-85 88-116 65 1-2 1,000 00:15-01:00 45 1
86 116 65 3 12-18 01:30 30 2
87 116 65 4 11-15 01:45 15 3
88 116 65 4 12-16 01:55 10 4
89 116 65 4. 5 12-16 02:10 15 5
90 116 65 4. 5 12-14 02:25 15 6
91 116 65 4. 5 12-16 02:30 5 7
92 116 65 4. 5 10-18 02:33 3 8
8-3-2000 35
8-3-2000 36
Days Qty. Tool Description & Report Serial # Est. Price
1 1 8-3/8 SOD x 7-1/4 SID Scallop R.Shoe 2965 $ 2010.00
1 14 Jts. 8-1/8 o.d. wash-pipe ( 434 ) Pearland $ 985.00
1 1 4-1/2 if x 8-1/8 wp pin canfield bushing 21047 $ 390.00
1 1 6-1/4 od Bowen Fishing Jar x 4-1/2 if 9202071 $ 1450.00
1 1 8-1/8 wash pipe slips 96777 $ 275.00
Days Qty. Tool Description & Report Serial # Est. Price
T.I.H. Tagged top of fish @ 6572. Got over
T.O.F. and slacked off to the cement @ 6656.
Started milling over fish @ noon. Milled over
fish 12 hours from 6656 to 6710. Mill quite.
New Page for 03-16-99
Circulate hole clean and start P.O.H. @ 2.00
A.M.
Sub
Total
Previous
Total
$6402
$2895
$9297
Example Job Report
8-3-2000 37
8-3-2000 38
Drilling is impeded by junk in the hole
Junk will fit in
standard junk
basket?No
Run Poor Boy Junk basket, Magnet
or Junk Mill
Yes
FormationHardRun magnet
or jet basket
Jet Basket Magnet
Run magnet
Run jet basket w/no float to 30 ft.
above junk. Establish parameters
Wash down to top of junk while
circulating volume of DP.
Drop ball and circulate down. Once ball
has seated, circulate at maximum
pressure and work basket down to TD.
It is not necessary to cut core
TIH to 30 ft. above junk.
Establish parameters
Wash down to junk while
slowly rotating
Stop pumps and lower magnet
to bottom then POOH.
POOH
w/recoveryNo
Yes
Run junk
milling
assembly
Job complete
POOH
w/recovery
Run jet basket
(no float)
Soft Run Globe,
RCJB or jet
basket
Jet Basket
RCJB
Run RCJB w/no float to 30 ft. above
junk. Establish parameters.
Run Globe Basket with
or w/out float.
Wash down to top of junk while
circulating volume of DP.
TIH to 30 ft. above top of
junk and establish
parameters
Dropball and circulate down. Once ball has been
seated, circulate at maximum pressure and work basket
down to TD. Cut core equal to head and barrel
While rotating lower
basket down to junk and
cut core equal to barrel
capacity
Yes
POOH
W/Recovery
?No
Run junk
milling
assembly
Yes
POOH
w/recoveryYes
Yes
Job complete
8-3-2000 39
Junk in the Hole
• What is the junk? size, weight, condition?
• Is it magnetic?
• Will junk fit into standard junk basket?
• Is the junk millable?
• The choices are to pick it up or mill it up.
• May require a combination of tool runs.
8-3-2000 40
Fishing Magnets
• All small objects with magnetic attraction
• Run on pipe; capability/rotate/ circulate
• Must wash fish; surface/ magnetic pole
• Run boot basket above for small junk
• Most, but not all tungsten carbide bit inserts
are non-magnetic
8-3-2000 41
FISHING
MAGNET
8-3-2000 42
Boot Basket
8-3-2000 43
Complete Recommended Connection Maximum Bore Overall
Assembly Hole Sleeve Length
Number Size O.D. (in.) (in.)
471-000-4 4-1/8 x 4-1/2 2-3/8 Reg. 3 11/16 1 32
471-140 4 - 5/8 x 4- 7/8 2-7/8 Reg. 4 1 32-1/2
471-140 5 x 5-3/4 2-7/8 Reg. 4 1/2 1 32-1/2
471-145 5-7/8 x 6-3/8 3-1/2 Reg. 5 1 1/2 32-1/2
471-145 6-1/2 x 7-3/8 3-1/2 Reg. 5 1/2 1 1/2 32-1/2
471-150 7-1/2 x 8-1/8 4-1/2 Reg. 6 5/8 2 34
471-150 8-5/8 x 9-5/8 4-1/2 Reg. 7 2 34
471-160 9-5/8 x 11-3/8 6-5/8 Reg. 8 1/2 3 36
471-160 11-1/2 x 13 6-1/2 Reg 9 5/8 3 36
Weatherford Type P Boot Basket
8-3-2000 44
Fishing Magnets
• Adapters available to run on wireline
• Usually inside casing with clear fluid
• Prior to running, check charge, sledge hammer
• Will hold hammer, will hold junk
• OD magnet; 1/4 to 1 less/ hole size
8-3-2000 45
Procedure run Magnet
• TIH Stop approximately 30 from bottom
• Circulate and ream to bottom/ circulate all fill
off fish
• Slack off a little while rotating a few rounds
• Don’t rotate excessively
• A magnet is not a drilling tool
8-3-2000 46
Operating Procedure
• Rotary will slap as guide rakes fish/ face
• Cut Lip/ cripple type guide best suited
• Set 2,000# to 3,000# weight on magnet
• Stop circulation, POH don’t rotate
• Guide prevent fish rubbing off while POH
8-3-2000 47
Bowen Itco Type Junk Basket
• Soft to medium formation
• Top sub,barrel, carbide shoe
• Two free rotating catchers
• Mill O D 1/4” less hole size
• Carbide I D same as catchers
8-3-2000 48
Operation:Core Basket
• Ream last 30’ to bottom
• Slow pump rate & RPM
• Watch torque as junk rolls in
• Increase weight 2- 4,000 Lbs.
• Cut core: stop circulation/ rotary
• Pick up to break core
8-3-2000 49
Core Type Basket
• If no junk recovery is made, but a good core
is recovered, normal drilling may be
resumed.
• Because it cannot produce any reverse
circulating , the globe type basket is used
primarily in open hole.
8-3-2000 50
8-3-2000 51
Bowen Itco Type Junk Basket DimensionsBasket # Hole Size Shoe O.D. Barrel O.D Max. Fish
14590
14586
14595
14600
14506
14610
14615
14620
14625
14630
14635
14640
3-3/4x4-1/8
4-1/4x4-1/2
4-5/8x5
5-1/8x5-1/2
5-5/8x6
6-1/8x6-5/8
6-3/4x7-1/4
7-3/8x8-1/4
8-3/8x9-1/4
9-3/8x10-1/4
10-3/8x11-7/8
11-3/4x14-1/4
3-5/8x4-1/8
4-1/16x4-1/2
4-1/2x5
4-7/8x5-1/2
5-3/8x6
5-7/8x6-5/8
6-1/4x7-1/4
7-1/8x8-1/4
8-1/8x9-1/4
9-1/8x10-1/4
10-1/8x11-7/8
11-1/4x14-1/4
3-5/8
3-1/4
3-7/8
4-1/4
4-3/4
5-7/8
5-3/4
6-1/2
7-1/2
8-1/2
9-3/8
10-3/8
2-23/32
2-31/32
3-9/32
3-9/32
4-1/16
4-5/16
4-3/16
5-7/16
6-3/16
7-3/16
8-1/16
9-1/16
8-3-2000 52
Reverse Circulating
Junk Basket
• Circulate capacity of string
• Check ID’s/ insure ball will pass
• Drop ball: shear pins: reverse
• Not necessary to cut core
• Hyd. power deflects junk/barrel
• Preferred tool for hard formation
8-3-2000 53
Bowen (W7R) Reverse Circulation Junk Basket
Hole Size Barrel O.D. Max. Dia. Of Fish
3-3/4 x 4-1/8
4-1/4 x 4-1/2
4-5/8 x 5
5-1/8 x 5-1/2
5-5/8 x 6
6-1/8 x 7
7-1/8 x 7-1/2
7-5/8 x 8-1/2
8-5/8 x 9-1/2
9-5/8 x 10-3/8
11-3/4 x 13-3/8
3-5/8
4-1/8
4-1/2
4-7/8
5-3/8
5-7/8
6-3/4
7-5/16
8-3/16
9-1/8
11
2-3/4
3
3-3/8
3-5/8
4-1/16
4-5/8
5-1/4
5-5/8
6-1/2
7-1/8
8-5/8
8-3-2000 54
BOWEN FULL-FLOW REVERSE CIRCULATION
JUNK BASKET
8-3-2000 55
Bowen Full Flow Reverse Circulating
Hole Size
4-1/8x4-1/2
4-5/8x5
6-1/8x6-1/2
7-1/2x8-1/4
8-3/8x9-1/2
9-5/8x10-5/8
10-3/4x11-5/8
11-3/4x12-1/2
Barrel O.D.
4
4-1/2
5-3/4
7
7-7/8
9-1/8
10-1/8
11
Maximum Dia. Fish
2-1/2
3-1/16
4-3/8
5-1/8
6-1/16
7-1/16
7-11/16
8-5/16
8-3-2000 56
Cone Dimensions
• Know your dimensions
• 7-7/8” bit cone = 5-17/64” OD
• Bowen Itco Type Junk Basket: 7-1/8”OD
barrel x 5-28/64”ID
• Weatherford type H Junk Basket:
• 7-1/2” OD barrel x 5-40/64 ID
8-3-2000 57
8-3-2000 58
8-3-2000 59
Junk Shot
• Shaped charge to break up junk into smaller
pieces so it is fishable
• Circulate fill off junk
• Tag fish and fire shot
• Run in open hole only
8-3-2000 60
POOR BOY
BASKET
8-3-2000 61
Poor Boy Baskets
• Fish is too large for conventional baskets
• Should be 1/2 smaller than hole ID
• Dressed with finger type bottom
• Fingers bend in: catches junk
• Lead, rubber, chain or wrench
8-3-2000 62
Poor Boy Baskets
• Carbide,wire, dimple rings, rods
• Relies on friction
• Mild steel for bending
• Custom made for a particular job
• Usually one of a kind, used only once
8-3-2000 63
Peen Shoe
• Burned over packer
• Perforation gun
• Shepherds hook
• Drill pipe rubbers
8-3-2000 64
Wire Catcher
• Hammer
• Lead
• Rubber
• Chain
• 24” pipe wrench
8-3-2000 65
Spring Tine
• Small OD sub or mill
• Perforating gun
• Shepherd’s hook
8-3-2000 66
Spring Tine Basket
Given:Milling on junk inside 2.992 ID
• 2-7/8 O D mill twisted off at box leaving
fishing neck of 2-1/4 OD x .75 long
• Successfully recovered fish with 2-7/8 OD
spring tine shoe
8-3-2000 67
Available Overshots
• Series 150 x 2-7/8” OD ; Max. catch = 2-1/8
• Series 70 short catch to catch 2-1/4 is 3-5/8
• Series 10 slim hole x 2-13/16 with maximum
catch of 2.330 was unavailable
• Series 20 short catch x 2-7/8” o.d.: Max. catch =
2-5/16 was unavailable
8-3-2000 68
Match Tool With Junk to be Fished
Junk Fishing Tool
1. Drill Bit Cone
2. 24” pipe wrench
3. Tong Dies
4. Drill Bit
5. Chain
6. Hammer
7. Wire Rope
8. Rubber
9. Lead
10. Shepherd’s hook
A. Magnet
B. Mill
C. Boot basket
D. Core Type basket
E. Reverse Circ.
F. “Po-Boy” basket
G. Ping Shoe
H. Wire Catcher
I. Spring Tine basket
J. Rope spear
K. Impression block
L. Wash pipe
M. Rope spear 2 prong
N. Taper Tap
8-3-2000 69
Match Tool / Junk
Drill Bit Cone - A,D,E
Magnet if only one cone, Reverse basket or po-boy basket if more
than one cone.
24 pipe wrench - D,E,F,H
Core type basket, reverse circulating basket, po-boy basket, wire
catcher basket
Tong dies - A,D,E,F,H
Magnet, core type basket, reverse circulating basket, po-boy
basket, wire catcher basket
Drill Bit K,N
Chain - A,D,E,F,H
8-3-2000 70
Hammer - A,D,E,F,G,H
Magnet, core type basket, reverse circulating basket, po-boy
basket, wire catcher basket
Wire Rope - J
Rubber - D,E,F,H
Core type basket, reverse circulating basket, po-boy basket, wire
catcher basket
Lead - D,E,F,H
Shepherd’s Hook - G,H,I
Ping shoe, wire catcher basket, spring tine basket
Perforating Gun - G,H,I
Match Tool/Junk
8-3-2000 71
BladedFlat Bottom
Junk Mills
8-3-2000 72
Mills
• Surest: more time consuming
• Run with boot basket
• Can spud lightly: break up junk
• Run 1/4” less than bit size
• Smooth OD, stabilizer pads/casing
8-3-2000 73
Mills
• Insert type best for pipe anchored
• Chatter and vibration are detrimental
• Use shock sub to cut down on vibration
• Carbide performs well in all conditions
• Neither performs well in abrasive formations
8-3-2000 74
Milling Rates:Surface Feet per MinuteCrushed carbide mills = 150 to 200 S.F.P.M.
Carbide insert mills = 150 to 300 S.F.P.M.
Surface Feet Per Minute = Mill Diameter X R.P.M. X .262
Example: Mill Dia. = 7”, RPM = 120, What is the SFPM ?
7” Mill X 180 RPM X .262 = 330 SFPM
R.P.M. = SFPM \ Dia. Mill X 3.82
Example: 330 SFPM \ 7” Mill X 3.82 = 180 RPM.
8-3-2000 75
8-3-2000 76
8-3-2000 77
Backoff Jet Cut Chemical Cut
8-3-2000 78
Ways to Part Pipe
• Controlled back-off (string shot)
• Chemical cutter
• Jet cutter
• Severing tool
• Mechanical cutters
8-3-2000 79
Stretch Formula
Any coupled Pipe
K = 1.4 ÷ weight of pipe per foot
Integral Joint tubing or drill pipe
K = 1.5 ÷ weight of pipe per foot
1,000,000 x inches in stretch
K x pounds of over pull
=Free Pipe
8-3-2000 80
Example
Packer set at 8,000 w/2-3/8 N80 tubing
String weight of 37,600; Mark pull @ 57,600
20,000# over pull; had 48 of stretch
1.4 ÷ 4.7 = .2978 (K)
1,000,000 x 48 = 48,000,000 = 8,059 free
.2978 x 20,000 5956
Conclusion? Stuck at Packer
8-3-2000 81
Est. Stuck Pt. = Tapered String
Measure stretch in inches with the following
overpulls:
• 2-7/8 D.P. = 25,000 lbs.
• 3-1/2 D.P. = 30,000 lbs.
• 4-1/2 D.P. = 35,000 lbs.
• 5 D.P. = 40,000 lbs.
8-3-2000 82
Formula for Tapered String
E.S.P. = 735,294 x e x W + L [1 - W2 ] P
W1
L = Length of big pipe ( above liner )
L = Length of small pipe (in or below liner)
W = Plain end weight of big dp (wo/tool Jt)
W = Plain end weight of small dp (wo/T.Jt)
e = Stretch in inches
P = Over pull
8-3-2000 83
Example Estimated Stuck Point
• What is the estimated stuck point for this
tapered string?
• Given: L = 10,000 & L = 2,200
• Plain end W = 17.93 lbs/ft ( 5x 19.5# )
• Plain end W = 12.31 lbs/ft (3-1/2 x 13.30)
• Stretch = 41 Over pull = 40,000 lbs.
8-3-2000 84
Observation
• If E.S.P.>L Stuck point is in or below L
• If E.S.P.<L Stuck point is in the upper string
and the formula ( method 2 ) should be used
and the estimated stuck point recalculated.
8-3-2000 85
Results of Formula
E.S.P.=735,294 x 41 x 12.31 + 10,000 [ 1- 12.31 ] = 12,412
40,000 17.93
• Since E.S.P.( 12,412 ) is > L (10,000 ), stuck
point is at or below L.
• This pipe is stuck in the B.H.A.
• The number 735,294 is a fixed constant.
8-3-2000 86
Method # 2
E.S.P. = 735,294 x e x Wdp
P
Where:
• e = Stretch
• Wdp = Plain end weight of dp(wo/T.Jt)
• P = Over pull
8-3-2000 87
Example
What is the estimated stuck point for this non-
tapered drill string?
Given:
D.P. = 12,500 of 5, 19.5 lb/ft plain end (tube)
wt. = 17.93 lb/ft
Stretch = 30
Over pull = 40,000 lbs.
8-3-2000 88
Results of Formula
E.S.P.= 735,294 x 30 x 17.93 = 9750
40,000
This number indicates that the pipe is stuck in
the 5 inch pipe.
8-3-2000 89
Calculations for Free Point in Stuck Drill Pipe
Single or Tapered Strings
Enter the Information in the Red cells below, an estimated free point will be calculated
Stretch in inches 41 Measure Stretch in Inches
Overpull in Pounds 40,000 the Following Overpull(s)
Length of Larger Drill Pipe 10,000
Length of Smaller Drill Pipe 2,200 2-7/8" DP 25,000.00
Plain-end weight of Larger Drill Pipe 17.93 3-1/2" DP 30,000.00
Plain-end weight of Smaller Drill Pipe 12.31 4-1/2" DP 35,000.00
Weight per/ft w / tool jt. on single string Drill Pipe 19.5 5" DP 40,000.00
EFP = Estimated Free Point EFP
Method #1 single string of drill pipe 13,325 Use the following Weights
For Drill Pipe
EFP Plain End W / Tool Jt.
Method #2 single string of drill pipe 13,513 2-7/8" DP 9.72 10.40
3-1/2" DP 12.31 13.30
EFP 3-1/2" DP 14.63 15.50
Method #3 Tapered String Larger / Smaller Drill Pipe 12,412 4" DP 12.93 14.00
4" DP 14.69 15.70
4-1/2" DP 14.96 16.60
Note: If Stuck point is Less than the length of Larger Drill Pipe 4-1/2" DP 18.69 20.00
use the answer from Method #1 or #2 5" DP 17.93 19.50
8-3-2000 90
Cable
HeadCollar Locator
Sinker Bars
(Weights)
Slip
Joint
(12”or
24”)
Oscillator
Upper Bow
Spring Assembly
(1” to 10”)
Stresstector™
Lower Bow
Spring Assembly
Free Point Tool
An electronic strain guage run
on a single conductor cable
used to measure torque or
stretch in a string of stuck pipe.
Tools are anchored to the pipe
I.D. at two fixed points by either
bow springs, dogs or magnets.
8-3-2000 91
Avoid pulling pipe into the
wall/ free point with torque
Pipe sticking here while
free pointing with
stretch, appears jars not
working below
Fishing Jars
Bumper Sub
Stuck Point
8-3-2000 92
Pipe Recovery Log
• Along with the free point, a pipe recovery log is
usually required to determine the best fishing
procedure.
• The pipe recovery log utilizes a sonic system
which sets up a vibration in the stuck pipe.
8-3-2000 93
Pipe Recovery Log
• The vibration, measured by a receiver,
decreases at stuck intervals in proportion
to the severity of the stuck condition.
• The logging instrument is calibrated in known
free pipe, normally near the bottom of
the last casing string.
8-3-2000 94
Pipe Recovery Log
• After recording, a signal attenuation scale is
placed on the log.
• This scale, expressed in percentages,
accurately indicates the severity of stuck
conditions at each interval.
8-3-2000 95
String Shot Backoff
A String Shot is the primacord and
blasting cap used to part a string of pipe.
A string shot Backoff is the unscrewing of
a tool joint or coupling with explosives at
a predetermined depth.
8-3-2000 96
Where to Back- 0ff?
Do you intend to fish the well?
No - As deep as you can
Yes - At least one joint above stuck point
Two joints above a key seat
100 feet below a casing seat
Not immediately below a dog leg or a
drop of angle
8-3-2000 97
Where to Back - Off ?
8-3-2000 98
Advantages of String Shot
• Can run in combination with free point tool
• Can run through smaller ID than cutters
• The shot should not damage the connection,
however lay shot joints down for inspection.
8-3-2000 99
Five Requirements for a Back Off
• Free - Connection must be free
• Torque - Correct left hand torque is needed
• Weight - Must be at neutral weight
• Shot - Proper size shot is required
• Across Tool Joint - The shot must be across the tool joint when fired
8-3-2000 100
Torque Required
• Tbg. 1/2 to1 1to11/2 3/4 to 11/4
• D.P. 1/2 3/4 to 1 1/2 to 3/4
• Csg.1/8 to1/4 1/4 to 1/2 1/8 to 1/4
Free Point Tighten Back-Off
8-3-2000 101
Shot Chart Example
Grains Per Foot
Mud 5000 10000 15000
4-1/2 10 200 300 350
14 300 350 400
18 300 350 400
8-3-2000 102
Other Uses S.Shot
• Outside back off
• Jar shot to free test plug out of well head
• Knock nozzles out of bit
• Knock plastic or corrosion off ID of pipe
8-3-2000 103
Pup Joints
• Use Pup Joints when doing wireline work
• Figure top fish/ space out/pup joints
• Easier working at rotary/ 20 in air
• Saves operator time and money
• Promotes safe work environment
8-3-2000 104
Chemical Cutter
Advantages
Flare Free Fish
Leaves No Debris
Will not damage adjacent string
Disadvantages
Heavy mud/problems
Limitations on depth
Slips can punch through corroded tubing
8-3-2000 105
Chemical Cutter
• Preferred method for tubing
• Must have fluid in hole
• Fluid prevents tool from jumping up the
hole
• Fire with 10,000 up strain
• 85% success rate
8-3-2000 106
Jet Cutters
Sizes available from 1-5/32” to 12”
OD to Cut 1.660” to 13-3/8” casing
Jet cutter works on the shaped
charge principle
Used to cut corroded tubing
Cutter will leave a slightly flared fish
8-3-2000 107
Super Jet Cutter
Works on same shaped
charge principal using more
explosives
Cutting deeper and under
higher hydrostatic
Will damage casing, used
mostly for P. and A.
8-3-2000 108
Severing Tool
• 2-5/8 O D tool will sever up to
11OD drill collars
• Used in open hole only
• Sizes available 1-3/8”to2-5/8”
8-3-2000 109
Severing Tool
Used mostly as a sidetrack
tool due to bad flaring
and splitting which
makes fishing difficult.
Fire in the tool joint, it will
only flare the tube area.
Hold strain up while firing
8-3-2000 110
Mechanical Internal Cutter
Cost Effective:
Shallow cuts
Large O.D. tubulars
Cut/retrieve in single trip
Well conditions too adverse for W.L.
8-3-2000 111