In recent columns, I discussed the basic fishing tools necessary for cable-tool or spudder operation. I recommend contractors have all the tools I discussed recently in their tool inventory. As I have also written, in many locations contractors can rent fishing tools if needed. Still, for work in remote locations, owning all these is probably a better policy.
In this column, I discuss a more difficult — though still rather common — fishing problem. Here, we have a string of tools stuck in the hole that still has the drilling cable attached and yet cannot be pulled out. This can occur when the drill string does not include jars. As I have said, some drillers would not drill a foot without jars in the drill string. I, for one, only used jars when necessary. (I even know of one drill rig and tool manufacturer that recommended not, I repeat not, using drilling jars when driving casing.) Yes, on occasion, I got my string stuck but I always got it out. But, if the string is really stuck tight, you need to cut the drilling line at the socket and remove the tools with a combination socket.
About Wire-Line Cutting Tools for Cable-Tool Fishing
The first step in this procedure is to cut the drilling line right at the socket. If you cut it more than a few inches above the socket, the leftover line interferes with the fishing tool getting a hold of the stuck tools. Then the fishing job becomes far more complicated.
The wire-line cutting tool is actually a selection of tools, all of which work together to cut the line:
- A small-diameter wire-line socket, generally with a 1.75-inch API joint
- A fishing jar with an 18-inch stroke
- A 10-foot-long, 2.5-inch diameter sinker bar
- The line knife itself
The assembled line-cutting string weighs about 325 pounds. Assemble it like any fishing string: socket on top, then the stem or sinker bar, following by the jars and then the knife.
Using Wire-Line Cutting Tools for Cable-Tool Fishing
The cutting line assembly runs from the sand line. (We can’t use the drill line because it is attached to the tools stuck in the hole.) Be sure the sand line on the rig has the capacity to lift the cutting tools, though this is usually not a problem.
It is absolutely necessary to attach the cutting unit to the line without the knives installed. This is done by sliding open a door-like plate on the knife body. Once attached, lower the cutting string a quarter of the way to the stuck tools, bring it back to the surface, lower it halfway to the tools, pull it to the surface again, and then three-quarters and back, and then all the way to the tools and back. This removes the twist in the sand line. It is also important to mark the sand line where the cutting outfit contacts the top of the stuck drilling stem. I consider it vital for the driller to take the time to do this and not hurry.
At this point, thoroughly clean and lubricate the inside of the cutting knife body, knife seats and knives. They can have no dirt whatsoever on them. Heavy lubrication is not necessary, just a nice coating of oil. Attach the knife unit to the sand line closed. Lower the whole outfit to the top of the stuck tools. After starting the knife unit down the hole, do not under any circumstances attempt to remove it from the hole until you get the drilling line cut. When the knife reaches the top of the stuck tools, put the drill line under moderate tension and cutting can begin. Using an upward motion on the sand line, perform several quick, sharp hits and the drill line should easily sever.
Removing the Cut Drill Line
After severing its connection to the tool string, you can usually pull the drill line from the hole with ease. Sometimes the drill line and sand line tangle and they then have to be removed at the same pace, first one and then the other. A bar, pipe or even a wooden pole placed between the lines helps separate them as they come out of the hole.
With the drill line cut, you can remove the cutting tools from the sand line. You now have a stuck drill string primed for fishing. If you followed proper procedures, you have cut the drill line right near the socket, getting you a step closer to getting the stuck tools out. Next time, I discuss the catching and removing those stuck tools using a combination socket.
As I write this column at the end of April, we have had a weird weather month here in southern Michigan. Two days ago, we had snow driven by a heavy wind and that severely limited visibility. Yesterday morning we had heavy frost, with the ground dusted in white. Nearly every night dropped below freezing — not very spring like. My infamous lawn is all green and ready for mowing, although I have not done that yet. The local farmers have their tillage equipment and planters attached to their tractors. They are ready and eager to go to the fields but the ground remains too cold and wet. It will get warm eventually and then probably get very hot after a few nice days.
Until next time, work hard, work safe and avoid those fishing jobs.
For more John Schmitt columns, visit www.thedriller.com/schmitt.
A Lifetime in Drilling
We interviewed columnist and former NGWA President John Schmitt for our Drilling In-Site video series. Click here to hear him share his cable-tool expertise and wisdom earned with decades in the industry.
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