Function : Releasable back off spear is a tool designed to recover and back off the stuck
pipe-shaped fish like drill pipe, oil tubing, etc. Back-off operation and fishing job are performed
through the interior bore of the fish by using the spear. The held fish can also be released
down hole when required. Moreover, the washing fluid can be circulated.
Applicable documents: SY/T5069-2000
operational process
Inspection the dimensions of the tool slip, decide it whether be fit for the dimensions of oil tube
or drill pipe.
Lays down the tool at distance to 1-2 metres of the fish top, start circulating and flushing fish
top. After the circulation normally, pump off, mark the hang weight slowly maintaining
the right-hand rotation. and getting down the tool when the weight indicator returns falls , stop
rotating and stop down the tool.
Raise the drilling rig and back off it, when rotate left torque decreased, show it was finished back
off, hoisting and Raises the fish outside the oil well
Stop raising if the tool accomplish the maximum loading, then roll off fish, The method is
as follows;
Bump down, Dextrorotary 1/4~1/2, pick up , will be able to withdraw the fish from the tools.
the type and main parameter of Releasable back off spear
|
type |
O.D. mm |
connection |
usable range |
Max. load KN |
back off pulling and torque |
|
|
pulling power KN |
N.m torque |
|||||
|
DLM-T86×48 |
Φ86×600 |
Nc26LH |
48 pipeline salvage Flip |
150 |
95 |
1750 |
|
DLM-T95×60 |
Φ95×600 |
2 7/8REGLH |
60 pipeline salvage Flip |
330 |
147 |
4313 |
|
DLM-T105×73 |
Φ105×650 |
Nc31LH |
73 pipeline salvage Flip |
500 |
166 |
5700 |
|
DLM-T121×89 |
Φ121×750 |
Nc38LH |
89 pipeline salvage Flip |
650 |
190 |
9590 |
|
DLM-T121×102 |
Φ121×810 |
Nc38LH |
102 pipeline salvage Flip |
780 |
190 |
10720 |
|
DLM-T140×114 |
Φ140×840 |
Nc38LH |
114 pipeline salvage Flip |
800 |
196 |
11520 |
|
DLM-T140×127 |
Φ140×870 |
Nc38LH |
127 pipeline salvage Flip |
860 |
196 |
12320 |
|
DLM-T154×140 |
Φ154×920 |
Nc50LH |
140 pipeline salvage Flip |
880 |
196 |
13260 |
|
DLM-T175×178 |
Φ175×1000 |
Nc50LH |
178 pipeline salvage Flip |
1650 |
290 |
13260 |
|
DLM-T220×219 |
Φ219×1200 |
Nc50LH |
219 pipeline salvage Flip |
1800 |
340 |
19000 |
|
DLM-T250×245 |
Φ250×1300 |
Nc50LH |
245 pipeline salvage Flip |
2250 |
340 |
22370 |
|
DLM-T280×273 |
Φ280×1400 |
Nc50LH |
273 pipeline salvage Flip |
2500 |
390 |
23242 |
|
DLM-T345×340 |
Φ345×1650 |
6 5/8REGLH |
340 pipeline salvage Flip |
2750 |
390 |
24710 |
