In my last several columns, I wrote about selecting the parts of a tool string for a cable-tool or spudder operation. We selected a drill bit, drill stem, perhaps drilling jars, and a then wire-line socket. We chose a drill rig of proper capacity equipped with a drill line, sand line and (hopefully) casing lines — all also of proper capacity. We are ready to go drilling, right? Well, not quite. We still have a few more tools to procure for our cable-tool operation.

The first thing we need is a set of tool wrenches. The tools I mentioned in paragraph one are held together by tool joints. These tapered joints come in assorted sizes, all of which have a shoulder at their major diameter. Generally, manufacturers standardize these joints to dimensions defined by the American Petroleum Institute — hence the name API joints. This ensures tools from one manufacturer work for those of another. At one time, apparently, manufacturers each had their own designs and dimensions for joints. I have known at least one driller (and a good one at that) who used non-standard joints on his smaller-diameter tools. Most drillers, however, use the API standards. For spudders, these sizes vary from a joint with a 1.75-inch major diameter used in 3-inch wells, up to a joint with a 5-inch major diameter for larger holes. That appears to be the largest joint you can buy tools for. I know of two larger API joints, but catalogs do not list tools with these sizes.

Whatever the size of the joint, we need a tool wrench to tighten it. Each joint has a collar on both the pin (male) end and on the box (female) end. On those smaller 1.75-inch joints, the collar is 7/16-inches wide, and on those large 5-inch joints the collar is 1-3/16-inches wide. The joints are designed to make a good tight fit on the tapered thread and then, when the collars come together, to make a really tight joint that will not come apart unless we want it to. These tool wrenches are not adjustable, but designed for each joint and attached to a square or flat a few inches from the collar. These squares and flats are generally the same dimension as the large dimension of the tool joint, so we have to select a wrench for each tool joint. There are, however, some liners that users can put into the tool wrench to adjust it to one size down.

Tool wrenches are made in the shape of a J and used in sets. They both tighten and loosen the tool joints. The smallest size made is roughly 3½-feet-long, a foot wide over the J, and about 2-inches thick where it engages the squares and flats. Cast from iron, they weigh about 50 pounds each.

To make up our tool string we hand-thread joints together laying on the ground, at least for the joints between the socket and jars or socket and stem. We then attach the tool wrenches and use a further device called a tightener to really squeeze the ends of the tools together. We also call this device a bar and chain, and it is simply that: a steel bar with two chains attached a few inches apart at one end. These tighteners come in three sizes for ever-larger joints. The ends of the tool wrenches have a claw with a slot and a chain from the tightener insert into the slot. The driller then applies force to the other end of the bar creating a lot of torque on the joint.

Keep these joints in good condition, free of rust and damaged threads. Manufacturers make thread protectors for both the male and female ends, and I highly recommend their use.

According to my calculations, you can apply roughly 1,360 foot-pounds of torque to a joint using the small wrenches for 4-inch tools, for example, and a number one bar and chain, and then pulling about 50 pounds on the bar. Properly tightened, that joint will stay together well for a year or more of drilling, provided it is clean with no damaged threads, the collar faces are clean and flat, and the joint is lubricated by a coat of oil (#10 or 20 engine oil works fine). The joint will also come apart easily when required.

Keep these joints in good condition, free of rust and damaged threads. Manufacturers make thread protectors for both the male and female ends, and I highly recommend their use.

For larger joints, the tool wrenches can get quite heavy. Wrenches for those large 5-inch joints I mentioned weigh about 185 pounds each and are proportionately larger in every dimension compared to their smaller brothers. You can tighten these larger tool wrenches with the largest bar and chain, but preferably you would want a circle jack.

A circle jack is a steel piece that looks like about one-third of a circle. It has notches along its length, similar to a mechanical jack that clicks when used to lift things. The circle jack has a traveler that engages one tool wrench and moves along the track operated by a handle, just like a mechanical jack. The other wrench braces against a stationery post, and you tighten or loosen the joint in this manner. I have never used one of these circle jacks, but they can obviously put a large amount of torque on a tool joint when necessary. I understand that a circle jack can damage or perhaps break smaller joints when when they are still above ground. The proper tightening of joints is another part of the cable-tool operation that makes it an art form learned from experience.

The tool string has to be assembled, at least partially, while it lays on the ground. I do not how one would use a circle jack in that circumstance. Perhaps you would use the largest bar and chain to get the joints tight enough that they stay together until some hole has been drilled, then a circle jack can do the final tightening. I want to reemphasize here how important proper care of cable-tool joints is. It helps ensure a tight, lasting connection.

Next time, I will write about some of the many other tools we need for a complete cable-tool operation.

We have had a goofy winter here in southern Michigan, with a few light snows but cold temperatures and a nasty wind most days. As I write this in early February, we just had the heaviest snowfall in seven years — at least according to the TV weather people. It is snowing as I write this, but my John Deere lawn tractor sits at the ready with a 4-foot snow thrower on it. I have moved snow before and will hopefully do it again. Until next time work safe, and if it has snowed in your area hopefully you can do some skiing or snowmobiling.

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