overshot oil and gas factory

PARVEEN Wireline Overshots are used retrieve a fish lost in the well that does not have a conventional fishing neck or a damaged fishing neck on it. The tool is operated by applying the weight of the tool string on to the fish. This will allow the slips to expand around the fish when the tool string is picked up, the slip will engage the fish. These are non releasable type overshots.

A downhole tool used in fishing operations to engage on the outside surface of a tube or tool. A grapple, or similar slip mechanism, on the overshot grips the fish, allowing application of tensile force and jarring action. If the fish cannot be removed, a release system within the overshot allows the overshot to be disengaged and retrieved.

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Tianhe Oil Group Co. Ltd. is a global group. We are specialized in the production of drilling tools, including R&D, production, selling, leasing, maintenance and services. Tianhe has 5 main businesses spread across the globe in more than 50 countries in the world.

Tianhe Oil Group management prioritize its people, technology, continuous improvement and building brand awareness. Our mission is to continuously strive innovation and improvement and expand our business in the oilfield. We increased the investment in technology research and development, always looking to provide our global customers with the best technical products and services.

Tianhe Oil Group strongly believes and promotes Total Quality Management, implements the ISO quality management system, HSE management system and API standards. Our manufacturing facilities are well equipped with four automated induction heat treatment lines and dozens of other types of heat treatment ovens and well furnaces (Box type, well type, carburizing heat treatment furnace) to ensure full coverage of heat treatment required by the different products.

So far, Tianhe Oil Group has established strong business relationships with over 200 international oil & gas companies in supporting the top 50 oil producing countries. For example, we have partnered with Schlumberger, Halliburton, Baker Hughes, Weatherford, Shell, NOV, etc.

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In the modern era of oil & gas production, oil companies, drilling contractors, and drilling equipment providers have been focusing more than ever on optimizing drilling and production processes. Most of these improvements focus on cost efficiency, reduced process turnover time, safety, and meeting the ever-increasing levels of environmental controls mandated by statutory and regulatory bodies. Today’s tooling requires reliable operation in the harshest climates, seismic design, resistance to sour gas, as well as ever-increasing temperature and pressure ranges.

Mechanical Research & Design, Inc. specializes in a wide variety of oil & gas drilling and production tooling, from weld and bolt on seal housings to complete design-build drilling stack solutions. We specialize in pressure rated, industry certified, drill through and well control solutions as well as the ancillary structural equipment that supports these product solutions. Our products can be found on and offshore all around the globe supporting land-rigs, offshore platforms, and drill ships. We began by designing and manufacturing mud containment seal housings over 20 years ago and most of our equipment is still in operation, providing maximum flexibility, adjustability, and reliability for decades yet to come.

Mechanical Research & Design, Inc. prides itself on rapid engineering and manufacturing response from custom design adaptations to conventional drilling stacks and systems, and including rapid certification turn-around. Our staff is trained and experienced in the design and fabrication of many offshore drill plant solutions from the drill floor through down hole tooling. We provide an expansive array of drill through stacks and equipment utilizing our SEALFAST® Sealing Connectors; lifting and handling equipment; stack up and make-up platforms for dual purpose; well control equipment support structures; and a host of other customized tools you won’t find anywhere else in one location.

By utilizing our time-tested SEALFAST® inflatable and mechanical seals and packers, we are able to offer many flexible and configurable drilling stack solutions. Our products allow users to adjust for the height, angular alignment, and eccentricities in the drilling stack with unparalleled speed and efficiency. Our, fixed, telescoping, and spherical adjustment riser and mud flow line systems can be designed to accommodate down hole pressures from 5-2000 psig pressure ratings, with process mud temperatures of up to 300° F. Our active sealing technology continues to provide optimal sealing on mandrels and reducing faces, even if they corrode and wear over time, leading to lower maintenance costs

Mechanical Research & Design, Inc. designs and manufactures an assortment of fully certified Diverter and BOP support, restraint, lift, and storage equipment. Most units come certified for offshore portable equipment lifting and can include rated tie-down to deck structural steel for divert and upthrust events. Units can be adapted for integral nozzle load restraint for mud flow lines and safety rated work platforms. These frames are also used as make-up and load-rated hang-off platforms for surface drilling stacks.

Drilling riser and conductor make-up, hang-off, and stack-up support frames and modules are critical to drilling operations. We fabricate modular deck-slot frames rated to API® structural codes and for use in seismic zones, integrating to existing structural steel for weight and upthrust load transmission. Many of these frames can support dual operations such as lift/lower operations, conductor string cement verification, and manual to automated riser centralizer solutions. In addition to this, Mechanical Research & Design, Inc. provides hydraulic lifting and running tools, split handling clamps and spiders, and through bore access covers for safety. Most of these units can also carry Lloyd’s®, DNV®, or ABS® certifications.

We also design and manufacture an assortment of controls, enclosures, and hose management equipment solutions for offshore use. From ASME® certified pneumatic and hydraulic control panels to CSA®, UL®, and Atex® Hazloc Electrical Panels, we can provide most customized options for low and high pressure maintenance and monitoring for offshore portable or fixed location use. To support our panels, we provide manual and automated hose management systems and fire-rated umbilicals with API® certifications.

No matter your specific application within the oil and gas industry, Mechanical Research & Design, Inc. can meet your needs with a combination of specialized product lines and specialized applications of standard products. We feature a wide range of standard products ideal for use both on and offshore, such as our weld testing and isolation repair solutions. In addition to the oil and gas sector, our solutions can be found in nearly any industry that requires sealing, pressure testing, isolation, packaging, or part handling. We can customize most of our standard solutions to fit any unique need.

I debated on where to go next, but at the end of the day the most widely used fishing tool has to be an overshot. Some will say why not a spear? Well if you must ask, always go with the strongest fishing tool you can run to catch the fish. And if you run a spear, never plug the I.D. of your fish by breaking it off. Done with that!

The info that follows has been taken from the manuals published on overshots. I realize that paper manuals are a thing of the past, yes, yes at one time fishing tool hands carried massive catalog brief cases full of reference material. Now you have the luxury of your laptop loaded with information. If you have never sat down and read an overshot manual, now might be a good time.

The overshot is highly versatile and efficient tool. There are several different types of overshots, however each overshot is designed to engage a specific size of tubing, pipe, coupling, tool joint, drill collar or smooth OD tool.

The original overshot was developed by Bowen Oil Tools, which is now part of NOV. One thing I will point out is that in the catalogs you will see more than one assembly number for a given OD of Overshot, this came about due to the two locations developing their own variations. I found this information on NOV’s website and thought it was interesting to share.

In the early 1930s, the consequences of the stock market crash prompted S.R. Bowen to consider starting a company in Houston, where oil exploration and drilling was accelerating. In the early spring of 1934, his son Walter and a friend formed Bowen Company of Texas.

Bowen™ became a leader in innovation with the creation of the first overshot, the Series 150, in 1935. This tool set the standard for fishing equipment, and the quick acceptance of the tool assured the company partners that their business would be successful. The company continued to create new products, building a reputation for their well tool design and construction.

Currently there are several manufacturers of overshots, NOV (Bowen), Rubicon (Logan) and Applied Oil Tools (Gotco). These overshots are designated by a series number as follows:Series 10 - Sucker Rod Overshot

Overshots may be identified by one of the following, known as “type”:Full Strength (FS) - engineered to withstand all pulling, jarring and torsional strain

The basic overshot (from top down) consists of a top sub, a bowl, grapple, control, and a guide. In addition to the basic components, some overshots (Series 10 and 150) can be dressed with either a:Spiral grapple used if the fish diameter is near the maximum catch of the overshot, or a

The Series 150 Overshot features the ability to packoff on the fish. When the circulating packoff is not used, the fluid circulates down the drillpipe, aroundthe top outside of the fish, through the slip or grapple assembly, around the guide shoe and up the annulus.

When the circulating packoff is used, the annular space between the top outside of the fish and the inside of the lower part of the overshot is packed off, diverting the fluid flow down into the fish, making it easier to release and recover the fish. Packoffs usually are not high pressure devices but will often withstand sufficient pressure to establish circulation through the fish. Third party high pressure packoffs are available from various sources.

The extension can be installed between the top sub and the bowl of the Series 10, 70, and 150 overshots. It is used to extend the overshot bowl to:Allow the grapple to catch farther down on a fish that may be necked down at the top by having been pulled in two, or latched by an overshot and released several times, or to

A stop ring must be used where a fish OD reduces immediately below the catch area to allow the grapple to bite on full-size pipe.Example - catching a Hydril upset or EUE collar. If the upset of collar should pass completely through the grapple, the overshot may not be releasable.

If a stop ring is needed and the grappledoes not have a built-in stop, a stop ring can be run above the grapple, in the area between the Top Sub pin and the Grapple.

The Series 10 Sucker Rod Overshot is designed to engage and recover sucker rods, couplings, and similar items from inside tubing strings.Basket grapples are recommended for fishing for hardened and ground boxes (Sucker Rod Box).

The Series 20 Sucker Rod Overshot is a short catch tool which provides a means for engaging the exposed portion of a fish too short to be engaged with a Series 10 overshot.Uses basket grapples only

The Series 70 Short Catch Overshot is designed to engage the exposed portion of a fish too short to engage with Series 150 overshots.Uses basket grapple only

The Series 150 Releasing and Circulating Overshot is used to engage, packoff, and retrieve twisted-off lost tubing, drillpipecoupling, tool joint, casing or other similar fish.

Special Grapples:Nitraloy grapples may be available from some vendors. It is available only in the most popular sizes and is not commonly used on standard pipe.

A right hand wicker grapple converts a normal right release overshot to left hand release. This grapple is used where you expect to apply excessive right hand torque to release a packer, safety joint, etc. Note: Overshot will have to be released by left hand rotation.

Grapple Controls:Basket Grapple control packers have built in packoffs. These packoffs will hold various amounts of pressure, depending on the size of the fish and the condition of the packoff after engaging the fish.

High Pressure Packoff Assemblies:The High Pressure Packoff Assembly is an accessory to the Series 150 Overshots. It is used when high pressure circulation to the fish is required. It consists of a packoff sub with packing and packing rings and is installed between the top sub and bowl of the overshot. By running the packoff sub above the bowl, this design prevents the application of high internal pressures to the overshot bowl. The design of the High Pressure Packoff Assembly allows pressures two to three times the standard overshot packoff to be applied to the fish.

This information comes directly from the NOV manual for the Wide Catch Overshot. This is probably the first and only change to this common tool I know of in my career.

The Wide Catch Overshot provides the strongest tool available to externally engage, pack-off, and pull a fish that has been significantly worn. This tool has similar rugged design features and construction as the industry standard, Bowen Series 150 overshot, with the ability to interchange the Bottom Guide with the full range of existing components used with the standard Bowen Series 150 overshot.

In service, the Wide Catch Overshot (WCOS) takes a positive grip over a large area of fish and is capable of withstanding heavy pulling, torsion, and jarring strains without damage to the tools or the fish.

The WCOS has been designed to significantly increase the catch range of the OD of the fish to be caught, compared to the standard overshot. This enables a greater opportunity for a successful fishing operation in a reduced number of trips, thus reducing overall intervention costs for the operator. In addition to the large catch range, the WCOS has the ability to seal across very large extrusion gaps at both standard and high pressure and provide full circulation through the fish, should it be required.

New coarse threads have been introduced at the connection between the top sub and bowl to allow for quick assembly while maximizing the torsion and tensile strength.

Connections between the Top Sub/Bowl and Extension Sub have been designed to create a seal. This will prevent the connection from washing out should the overshot be required to be flowed through for a long period of time. In order to lock the Top Sub/Extension Sub to the Bowl from backing off during operation, set screws have become standard and will gall the threads should the connection break free.

The operation of all overshots is identical. The exception being that the Series 150 carries a packoff which provides circulation through the fish. First, determine that the overshot is properly assembled and dressed with the proper size grapple. Make up the overshot on the fishing string (normally it is run connected to the bottom of the bumper sub) and run it into the well. As the top of the fish is reached make sure circulation has been established to clear overshot ID of any plugging. Lower the overshot onto the top of the fish with no rotation at first. A 5,000 pound set down weight will be sufficient to engage the grapple. While lowering the overshot over the top of the fish watch for pressure build up, shut off pumps if any pressure build up is noticed. Should any back pressure be noticed, release the back pressure to allow the grapple to engage the fish. By elevating the string it can be determined, if the grapple went over and engaged the fish. If unable to work overshot over top of fish without rotation, then slowly rotate the fishing string to the right and gradually lower the overshot over the fish. Combined rotation and lowering over top of the fish are important to keep the grapple in the release position. This provides the maximum clearance between the grapple and fish. While lowering the overshot over the top of the fish, watch for torque build up and an increase in pump pressure. A pump pressure build up indicates the overshot has gone over the top of the fish thereby reducing the flow area. Stop rotation (continued rotation could dull the wickers of the grapple) enabling the grapple to set. Allow the right hand torque to slack out of the string and then pull on the string by elevating the string to set the grapple.

To release from the fish, bump down, then simultaneously rotate to the right and slowly elevate the fishing string. It is best to have a clean fishing top before running the overshot.

When you can’t reliably engage your fish with drillpipe, rely on the reliability and flexibility of fishing internal and external engagement tools from Baker Hughes.

Externally engage, pack off, and pull a fish with our wide range of overshot tools. The first fishing choice when screwing into the fish is not an option, our overshot tools are simply designed but ruggedly built. Choose from options including:

Kelo socket overshots are proven to catch small-diameter workstrings and sucker rods inside casing as well as recover coiled tubing that has parted and remains in hole.

The t-dog, mouse-trap, and flipper-dog (TMF) overshot can be dressed in three different ways for different washover applications. Deploy the t-dog assembly option to washover and recover mud-stuck or sanded-up square-collared pipe in one trip. Use the mouse-trap assembly to catch sucker rods, integral joint tubing, or cables. And with the flipper-dog assembly, you can confidently catch a fish with different ODs.

Hydraulic casing spears are run above a mechanical or hydraulic inside casing cutter, allowing cutting and casing pulling in one trip. The spears are set and released hydraulically for ease of operation and no need for mechanical intervention.

Type B™ and Type D™ casing and tubing spears retrieve a full range of casing sizes. The design of these spears affords easy dressing for alternate casing sizes, simple field-dressing to change the release setting, and fast, effective release—all of which help improve the efficiency of your fishing operations.

The Type E™ casing spearprovides effective casing retrieval in the most severe downhole environments. With its heavy-duty, high-strength design and simple construction you’re assured reliable performance and easy operation and maintenance for a wide variety of casing sizes and weights.

Fishing tool is a special fishing drilling tool used to retrieve fallen objects from the borehole. At any stage of the operation, the drill rig operator will encounter unexpected situations, such as falling drill string, stuck pipe, missing drill bit, etc. The equipment that falls into the well is called "fish" or "trash", and the tools used to remove the equipment are called "fishing tools." Sometimes it may be necessary to use "fishing tools" to retrieve older wellbore equipment, such as packers, liners, tubing, or any stuck objects in the well. The drilling tools for fishing must be retrieved from the borehole in order to continue drilling operations.

Overshot is a very common fishing tool. The main fishing object is a smooth tube fish, which belongs to the external fishing type (i.e. catching the external surface of the fish).

Taper tap and die collar are common fishing tools for fishing the inner hole of the string. They are used for fishing the inner hole with holes such as tubing, drill pipe, casing milling pipe, packer, water distributor, etc. It is made of high-quality alloy steel and especially heats treated. It has the advantages of high strength, high toughness, and simple buckle making.

Here’s how Schlumberger’s Glossary defines a “fish”: Anything left in a wellbore. It does not matter whether the fish consists of junk metal, a hand tool, a length of drill pipe or drill collars, or an expensive MWD and directional drilling package. Once the component is lost, it is properly referred to as simply “the fish.” So much for definitions. What follows is the rest of the fish story.

Oil patch fishermen are a special breed. The fish they seek live deep down in the earth and require specially designed gear to coax them to the surface. The fish oil patch fishermen seek are not live creatures at all, although some might disagree because of their uncanny ability to evade capture. No, oilfield fish are items lost downhole in oil wells and the fishermen are those specialists who remove them from their environment.

Beginning with the 150- to 500-foot oil wells of the 1850s and continuing to those technologically sophisticated 20,000 foot projects of today, one of the most consistent oil well drilling problems has remained how to retrieve unwanted items lost down the well bore. Whoever first called those lost items “fish” or called those who retrieved them “fishermen” has been lost to history. But regardless of how those terms originated, it is acknowledged by oil men everywhere that the unique skills needed for fishing are earned through long experience by persons with the rare ability to visualize what is happening thousands of feet below the surface. That combination of experience and skill is necessary because every fishing job is different, often requiring specially fabricated tools ofttimes created on the spot and possibly used only once.

In the very earliest days of the industry the drilling was done exclusively with cable tool rigs. It is known that they suffered numerous fishing problems but there are very few descriptions of the tools they used. It was not until 1884, with the publication of the Oilwell Supply Catalog of that year, that the first known illustrations of fishing tools came to light. Those listed in that catalog were considered standard devices used for common problems encountered in the retrieving items lost in the hole. There is little doubt that those standard tools were the result of thousands of predecessors created in local machine and blacksmith shops throughout the oil patch during the preceding decades and abandoned once the fishing job was completed.

Although designated as standard fishing tools, the items sold by the various supply houses such as Oilwell were not by any means used exactly for the specific purpose for which they were advertised. Many of them were modified on the job to fit the particular problem presented. By far the greatest problem encountered by the cable tool rigs involved lost manila rope or steel cable drilling line from which was suspended the drilling string. When one of those lines broke or for whatever reason got lost down the hole it had to be fished out. The most common tool used for that purpose was a spear.

The simple fishing spear was just what its name indicates. It was a long shaft from three to ten feet in length with a series of barbs welded to its sides facing toward the top of the tool. When the spear was lowered into the tangled mess of a broken drilling line at the bottom of the hole the barbs captured the line as the spear was withdrawn. Sometimes the single shaft spear would not grasp the lost line tightly and it slipped off the barbs. In that case there were spears featuring two or possibly three shafts arranged in a circle with the barbs welded to the inside of the circle in order to get a better grip and prevent losing the line through slippage.

Other implements for handling lost lines were the knife and the hook tools. The hooks worked similar to the spears only they were shaped like a fishhook. The knives on the other hand were simply designed to cut the drilling line in case it was so entangled the spears could not pull it out of the hole. Sometimes a combination knife and hook tool was used so the line could be grabbed by the hook and pulled to the inside of its bend, where there was a sharp cutting edge. Once the line was cut away from the tangled mess it could be fished out of the hole in smaller lengths. Also sometimes the drilling string became stuck fast, in which case those cutting tools were used to shear the drilling line as close as possible to the drilling string so a whipstock could be set to drill around the offending items.

Beyond drilling line retrieval tools there were a variety of grabs utilized to remove various cable tool items lost downhole. In the case of a string of tools lost but not stuck beyond removal there were several overshot tools that could be lowered over the string and when pulled upward would tighten around the jars—or whatever the top lost tool was—and pull the string out of the hole. Then there was the bailer grab, which was simply a tool similar to a two pronged spear without the barbs. At its bottom was a hinged pin that, when lowered over the bail of the bailer, would swing open and once past would drop back and latch into place, allowing the bailer to be withdrawn from the hole.

Those then were the basic tools used for fishing cable tool wells, along with a host of variations. They were all simple, common sense solutions developed over the years by hundreds of unheralded drillers, tool dressers, and a variety of other oilfield hands. As already mentioned there were literally thousands of variations on those basic tools all designed for problems encountered as well as to suit the particular inclinations of the fishermen who employed them.

When rotary rigs entered the mix about 1894 the downhole fishing problems tended to change somewhat with the advent of the new technology. The lost cable problem practically disappeared with the advent of the rotaries due to their using pipe instead of cable, but the numbers and variety of items lost downhole was absolutely amazing. They ranged from a roughneck simply dropping a wrench in the well bore to bit cones being broken off or maybe the drill pipe being twisted off.

It is from those types of incidents that have fostered some of the best illustrations of oilfield culture. For example the story of the boll weevil who dropped a wrench into the well bore that resulted in a five day fishing job. When the battered tool was finally retrieved the driller handed it to the hapless hand and proceeded to give him a real oil patch dressing down. When he was through the driller told the man he was fired, whereupon the roughneck looked the driller right in the eye and pitched the tool back into the hole. Some say that indicates the graduation from boll weevil to hand, but I can guarantee you it would cause a fistfight right then and there on the rig floor. Then of course there is the term “twisting off” in regard to accidentally severing the drill pipe. That term has come down over time to describe anything a hand might do to cause him undue grief, usually things involving imbibing large quantities of alcoholic beverages.

But I digress. Back to the subject at hand of fishing on rotary jobs. One of the most frequently utilized tools, at least in those early days, was a device called a junk basket designed to remove small objects lost downhole. A junk basket was constructed by cutting slender fingers in the sides of a piece of pipe, fastening it to the drill pipe in lieu of a bit, and lowering it into the hole until it touched bottom. Then the pipe was slowly rotated and weight gradually applied to the drill string. The weight increase and rotation caused the fingers to collapse inward and hopefully clutch the fish within its grasp. Over time that crude device was engineered into a more sophisticated tool, causing it to remain an important fishing tool for many years. In later times powerful magnets were sometimes attached to the bottom of the drill pipe in an effort to remove small items lost downhole.

The most serious of the fishing jobs, like those of the cable tools, revolved around lost suspension devices, which in the case of rotaries was drill pipe instead of cable. In the case of stuck pipe, either drill pipe or casing that could not be withdrawn from the hole, it might be necessary to save as much of the stuck pipe as possible. In the very earliest days that was accomplished by a nitro shooter lowering a shot inside the stuck pipe and shooting it apart. Or a device called a cutter could be lowered into the hole and actually cut the pipe apart. In either case the well might be saved if, after the severed pipe was removed, it was feasible to back uphole a little ways and use a whipstock to deviate the hole enough to bypass the stuck pipe. Otherwise the well was simply abandoned and at least some valuable pipe was saved.

Sometimes a heavy lead plug is lowered into the hole to get an impression of the nature of the top of the fish. If it is retrieved and the fish is shown to be all ragged and bent and generally a mess, as is often the case, it is possible to lower a special tool to grind the item down to a manageable size. When it is reasonably clear what the situation is, there are a variety of tools that can be utilized. They generally fall into the category of undershot or overshot in nature. That is, the undershot, which is lowered inside the offending pipe, or the overshot, which is lowered over the outside of it. Once in place those items have a variety of grabbing mechanisms to grasp and hold the pipe while it is removed from the hole.

Regardless of the exact nature of oilwell fishing jobs, two things are certain. First they normally take a long time. At the least a few days and some of them stretch into weeks. The second thing is that shutting down a drilling operation is an expensive operation and the least amount of time it takes the better. Hence the value of a good fisherman who can figure out what is going on way down below the surface.

The business of “fishing” a well bore requires skill, technology—both new and tried-and-true—and a mechanical aptitude as well. Like everything else, this trade keeps changing, too.

The Oilfield Glossary compiled by Schlumberger explains a complicated industry process in a few simple words. Those words don’t explain how difficult the procedure can be or that it can involve several days of work. In these times when more wells are being drilled vertically and horizontally and into more plays and with older wells being re-opened, fishing companies are fielding more calls for a crew and equipment to retrieve a lost object in a hole.

Workers new to the industry often are confused when they hear someone talking about “fishing” and “fishermen.” Looking around the parched land that comprises the Permian Basin, they wonder where the best fishing hole is located.

Historically, fishing has played an important role in the drilling industry. Schlumberger’s glossary noted that “It does not matter whether the fish consists of junk metal, a hand tool, a length of drillpipe or drill collars, or an expensive MWD and directional drilling package. Typically, anything put into the hole is accurately measured and sketched, so that appropriate fishing tools can be selected if the item must be fished out of the hole.”

“In the drilling process, a well bore can heave in on them, or a boulder can fall in the bore. The pipe gets stuck and the crew can’t get the pipe out,” he said.  Sometimes the fishermen, as the specialists are called, encounter hydrostatic stick. Fluid goes into the zone and pulls the item to the wall of the well bore, like paper being stuck to the wall.

Another situation is called “key seated,” said Johnson. “It’s like a keyhole in a doorknob. The drilling process hits a soft spot and the drill bit “walks off” and must be straightened back.

In some cases, a wireline truck is used to find out where the pipe is in the hole. “We go in with an overshot or use hydraulic jars to try to jar the pipe loose. We can go in with a wash pipe and wash over the string and pull it out of the hole.

“Sometimes there is pipe fatigue and the pipe will break off. We have to go in and retrieve it. Iron is iron and it’s going to break.” Another problem occurs when the earth’s magnetic field produces electrolysis and the pipes become stuck.

The Schlumberger Oilfield Glossary explains that special mechanical devices are used to help “fish” the equipment lost downhole. This equipment falls into four classes: diagnostic, inside grappling, outside grappling, and force intensifiers or jars.

The glossary explains that diagnostic tools can include a simple impression block to help the fisherman custom design a tool that can attach to the fish and remove it. Other diagnostic tools include electronic instruments and downhole sonic or visual-bandwidth cameras.

Inside grappling devices, called spears, usually have a tapered and threaded profile which enables a fisherman to guide the tool into the top of the fish and thread it into that top so the tool can be retrieved. Outside grappling devices, called overshots, are fitted with threads that “swallow” the fish and pull it out of the hole. Jars are mechanical downhole hammers that deliver high impact loads to the fish.

Problems also can occur once production is going. Johnson said a company will notice production is going down on a certain pumping unit and call in a fishing unit.  “The pipe could be stuck, the hole might have collapsed, or there wasn’t a good cement job in the pressure zone,” he explained.

Nabors Well Services, Ltd., is among the biggest of the Permian Basin’s well servicing companies and responds to a steady stream of requests for fishing operations. Craig Fletcher, operations superintendent for Nabors’ yard in Denver City, said the company is very busy right now.

“There are many different scenarios and a variety of services associated with what we do,” Fletcher said. “The best way to describe it might be to say that we provide remedial repair and fishing services and can deepen wells with our equipment.” Their customers include Hess, Oxy, Sandridge, Devon, XTO, and Apache, and calls take their crews up to northern and western New Mexico, South Texas, and the Eagle Ford play near San Antonio.

“For one reason or another, the casing and the tubing can get in bad shape and that is where we come in,” Fletcher said. “We encounter a lot of bad casing and we stay busy repairing it.”

The Permian Basin has its own unique challenges in terms of fishing services, and part of it is attributed to the success this region has known. The age of those wells and the drilling practices at that time can contribute to problems today. “The Permian wells have lasted so long and have been so prolific, that some of these wells have been producing over 60 years,” he said. “When these wells were drilled, it was never anticipated they would last this long. If the drillers had anticipated it, they would have run things differently, and made them even more durable than they did. They could have used thicker pipe, done better cement jobs.”

Fishing tools haven’t changed much over the decades, according to Hinton, who ventured in 1968 into the oil patch to first, plug wells, and then to service them before trying his hand at fishing.

“The changes have been very few,” he said. “Most of the tools are common: things like a grapple and a spear. We use a lot of mills that smooth the surface of the fish so we can get a better hold on it. Various sizes of tools are needed and we have to build up a good inventory.” In addition to sending crews out to the field, Hinton Enterprises offers equipment for rent. People who are experienced in oilfield work are the ones who will rent equipment and not hire a fishing crew with it.

Johnson with SERVCO added, “A lot of tools haven’t changed in years. You have a tool that works and nobody has come up with anything that works better.”

Weatherford International, a major player in the well servicing industry, also does a lot of fishing. Bobby Duncan, area manager for Weatherford’s Midland yard, said one of the biggest changes affecting the fishing trade is the trend toward more production work and away from as much “open hole” fishing.

Even as recently as five years ago, open hole work was more prevalent, he said. But the majority of new wells today are oil wells, and technological advances on those wells mean fewer reasons to fish.

Technology has changed some aspects of the business, though. Fletcher with Nabors noted that back when the wells were drilled in the 1940s and 1950s, “everything was rotary rigs. Now they have top-drive rigs and they can measure and log while they are drilling. They can steer the bit wherever they want.”

However, that can make the fishing more difficult, he noted. “If you drill a mile down and then a mile horizontal, you’ve got more frictions because the pipe is turned.”

Duncan, at Weatherford International, observed that newer technology has meant that fishing can be avoided entirely, in some instances. With steerable bits, drillers can turn the bit and can bypass the fishing chore. “They can simply back up the drill and take a different direction, bypassing the object that was lodged in the well bore.”

Another consideration that Duncan pointed out about horizontal wells is that the vertical portion, which is often  shallower than vertical segments on the older wells, is easier to fish because the job “doesn’t take as long to make a trip.” Conversely, “with a 15,000-foot gas well, it takes a lot longer to go [to the bottom].” He sees more fishing activity concentrated on the production end as contrasted with the exploration side.

Johnson has encountered more difficulty when fishing on some horizontal wells. “Some stuck pipes on a horizontal wells can be cased and some are open. There are different situations when you have to clean up something: how steep of an angle you need to go and how far out it goes,” he said.

In August, Hinton’s company was fishing at a horizontal well and encountering some problems. “It’s more difficult. You need specialty tools to go in the hole at a certain direction,” he said.

During past decades when wells were shallower, fishing posed a relatively economical option. “It was more cost effective to fish the gas wells then,” said Weatherford’s area manager. “Today, instead of spending money in fishing, it is easier and more economical to drill around it.”

Johnson noted that the New Mexico Oil Commission could become involved if the fish can’t be pulled out and the well needs to be plugged. The commission wants to know “where the well is, what damage it might do in the future and if any chemicals could get into the freshwater zone. They might require the well bore to be cased and plugged properly.”

“I’ve had some old tools from the late 1940s and early 1950s fished out. Some were homemade tools. Nothing was built to specs. We had to go to some oldtimers to see what they were,” Johnson said. Other items include submersible pumps, sucker rods, electric cables, and even the fishing tools. “We’re on a job now where we’re fishing out a submersible pump. Those pumps can be expensive. We’ve been on the job a week now. It’s not an easy job.”

Hinton, too, has seen a variety of articles pulled out of the holes, including trees that were used to plug a hole. These were found when a company tried to go back into the hole. “Sometimes a crew gets mad and quits and they throw all their tools into the well,” he added.

The hardest thing to fish out of a well bore, according to Nabors’ Fletcher, “are the fishing tools themselves. Yes, it does happen. We take precautions: we inspect them and replace them if there is any doubt about the strength or integrity of the tool. We might do a magnaflux inspection, check the wall thickness. You do everything you can to see that losing a tool won’t happen, but sometimes it does.”

“You can teach someone the fundamentals of the tools and how to use them,” Johnson said. “But it takes time and experience for them to learn it. You can’t just take someone off the street to be a fisherman. Even someone who works on a well can’t jump into this overnight. Someone who is mechanically inclined might catch on faster. This is a skilled profession. I have several good hands and all of them work production and open hole fishing. My hands are pretty steady; some have been here 10 to 12 years.”

“While they were eating, the kid asked the other hands what happened. Pointing at the reserve pit, he said he thought they were going to be fishing. The hands laughed and told the kid there were no fish in that lake (the reserve pit). The hands explained they had lost some drill collars in the hole and the fishing part was trying to retrieve them.”

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