1 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

Stay from under sheave while derrick man hangs it

Top
Use Longest Links Available Drive

108” ones are standard; try to use 140” ones or longer

Top
Drive
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 108”

cable rubbing; If one is not available, have rig make one >108”

Do not use the Varco Wireline Adapter commonly known

as “Bicycle Wheels”
Not
Desirable Desirable

Tension Device CMTD

Switch to TDK if using CMTD Schlumberger

(Prevents cable backlash)

(if available)
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 Schlumberger
hang freely until weight is applied
TDK
2 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 Cable

If hole is deviated, cut cable 10 feet above

rotary table plus 1 foot for every 1,000
feet greater than 10,000 feet
T-Bar T-Bar
Use proper size cable bushing in T-Bar
and mark cable to ensure there is no
slippage

Tapered
Cone

Rig Up Spearhead Overshot

Use tapered cones from LEH-Q on top of fishing weights

Highly Recommended
If available, use heavier-shorter fishing weights with Or Or
knuckle joints and swivel or Wire Rope Weight with Swivel

Minimum restrictions for all drilling hardware (jars, drill Knuckle

collars, and heavy weight) must be known to determine Joints

size of overshot guide to use

Always use the largest guide that will fit

through drilling hardware
Swivel

Never use “after-market” rope sockets

Overshot Guide

Work Order Number

Stamped Here
Rig Up Spear
Never use spears which contain “W’s” in their work
Hexagon Adapter
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

Never use “after-market” rope sockets

3 Assemble Overshot Make-Up Torque
Assemble 4-11/16” overshot, spiral type

4 11/16”
Bowl to Top Sub

5 3/4”
grapple, and no-go (preferred method) 5 3/4” 4 11/16”
7600 ft-lbs 3200 ft-lbs

If basket type grapple is used, assemble Bowl to Guide

5-3/4” overshot, basket grapple, and no-go 5 3/4” 4 11/16”
1700 ft-lbs 1300 ft-lbs

If fishing for AMS, use extensions to

engage below bottle-neck section and
choose appropriate guide shoe

ALWAYS VISUALLY INSPECT grapple

for proper size for job and NEVER install
a used grapple Not
Desirable Desirable

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)

Install Drain Sub

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

Install above downhole overshot assembly

4 Thread Through
Slowly pull overshot assembly to derrickman
to thread through bottom hole assembly

Make sure minimum restrictions are known

First Stand of Drillpipe,

Collars, or Heavy Weight

Remove T-Bar
Tighten overshot to bottom of first stand
of drillpipe Tightened Overshot
Assembly

Stab spearhead overshot, pull cable

tension, check for slippage, and remove
Cable Tension= 1000 lbs
T-bar cable clamp after completing check to 2,000 lbs + Normal

Remove IDW and position spooling arm

to one side (If CMTD is used, do not remove) Spear Stabbed into
Overshot

T-Bar

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

4 1/2 IF 3 1/2 IF

C-Plate
Location
5 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 derrickman

Derrickman will thread overshot

assembly through drillpipe

Schlumberger
Schlumberger

Flag Line Again

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

Schlumberger

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

Pay particular attention to top

drive; If weights are in danger
of hitting top drive, slack off Drillpipe
but do so carefully
6 Re-thread Overshot
Pull overshot to derrickman who will thread
through another stand of drillpipe
(watch flag at at drum)

Schlumberger

Stab Overshot Drillpipe

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

Schlumberger
C-Plate

Make Overshot Connection

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

C-Plate
7 Make-Up Drillpipe
Drillpipe is made -up and tightened
Slips are pulled and the descent begins

Do not rotate pipe in hole

Observe tension

Slips

Tripping in Hole 1 2
Repeat procedure for each stand Set Slips and
of drillpipe until circulation depth Disconnect
Overshot
is reached

If excessive open hole is present,

Trip in Slowly
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

3 4 5

Rethread Overshot Stab Overshot Make Overshot

Through Drillpipe Connection

Remove C-Plate

Then Make-Up
Drill Pipe
C-Plate
8 Install Circulating Sub
Install sub one stand above fish
Kelly or Top Drive
Spearhead Overshot

Circulating Sub
Circulating
Basket

Spearhead Sub Circulating Sub

C-Plate

Never put circulating sub in hole

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

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!!!

9 Blow Drain Sub Disk Drain Sub
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 blown out the overshot

Blown Disk

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
10 Install TIW Valve
Logging Cable
Install TIW valve before spooling
cable onto drum

This could aid in controlling well if TIW Valve

trouble occurs

OPTIONAL
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

To Logging Unit To Well

Spool Cable Square Knot

Observe square knot as it

goes over upper and lower
sheaves

Afterwards, reinstall IDW

to measure cable

Schlumberger
11 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 Downhole Overshot
tool collar and remove overshot assembly With Fished Tool

Remove remaining toolstring with air

hoist, cover hole, and finish breaking
and cleaning tools in rat hole
Make-up Plate

Make sure air hoist is rated for toolstring

Removing Fish Grapple

Remove guide and bump tool

vertically against rig floor to free
grapple control
Grapple Control
Spin tool and grapple out of overshot
by turning in a clockwise motion
(Tool should come free without Guide Shoe
applying excessive force)

If another method is used to release tool,

remove electronics from housing in
overshot to minimize damage