Innovating Well Casing Repair Technology

Swaging with the aid of inflatable packers is a way to maximize well rehabilitation.

By Todd E. Kerry and Philip M. Judkins

The traditional method of repairing a casing breach in our industry is to reline the well or even resort to the more costly option of drilling a new well.

Neither is a good choice in many cases due to site restrictions, limited borehole diameters that restrict installation of the pumping equipment, or cost. With that, swaging has become more prevalent as a cost-effective solution to relining wells.

Swaging is the art of expanding a thin piece of Schedule 10 stainless steel pipe to create a compression fit to another piece of pipe. In the water well industry, it is used to seal off undesirable water zones and repair holes in damaged and deteriorated well casing.

It’s particularly beneficial where the traditional method of relining a water well with a smaller-diameter well casing cannot be accomplished due to the reduced well diameter leading to a pump redesign at lower flow rates since the installation of larger pumping equipment is not a possibility.

New swage technology utilizes a perfectly round piece of Schedule 10 stainless steel pipe and an inflatable packer element to grab and swage the patch into place, providing a perfect cylindrical fit to the ID of the well casing.

Swaging provides minimal reduction in the borehole diameter, allowing you to maintain the well performance and maximum pumping equipment sizing. Typically, the sections of stainless steel are only one quarter inch thick, allowing passage of larger pumping equipment. Additionally, swaging can save your clients’ assets and investment by relining deteriorated or caving zones.

Swaging and Packers

Our company, Water Well Solutions, came across a project about 10 years ago that involved relining a 1500-foot well for a pharmaceutical company. In exploring the options available at the time, hydraulic swaging seemed to be the best application for the project as the project would support the upfront cost of purchasing a hydraulic swaging unit. After purchasing the unit, we hired the company that sold us the swage to perform the relining so that we could gain experience swaging wells.

The ability to use clean clear water versus hydraulic oil in potable water wells is an additional reason the pneumatic inflatable packer is superior to the hydraulic swage.

This experience taught us a lot of things. One, hydraulic swaging is slow, cumbersome, and risky. It took more than two months to complete the project, which we had not accounted for in our estimating, and many sections of the stainless steel swage had to be fished out of the bottom of the well, having been lost during the process.

Secondly, the final product did not leave a smooth cylindrical surface. It had left ripples, imprefections, and gaps in the sections of pipe that led to sharp edges that the submersible pump cable could get cut on or the pump could catch on during installation.

The stainless steel used in hydraulic swaging is corrigated, not cylindrical, allowing for the imperfections and reduced structural integrity. In addition, there is risk of rupturing the hydraulic lines that could leak hydraulic oil into the well, causing environmental issues.

We were involved in a project several years later which involved fishing out a 500 hp submersible pump that had failed and fallen to 1400 feet with 100 feet of 8-inch column pipe still above the pump and motor. The industrial client was asking for an alternative to fishing with an overshot due to concerns that pumping equipment may not be able to be removed due to a collapse in the formation and they did not want to risk losing more pipe or fishing tools in the well.

After investigating various fishing tools and options, we came across a pneumatic inflatable packer that the manufacturer assured us could be used to retrieve the pumping equipment by simply lowering the packer into the 8-inch pipe, inflating, and retrieving the fish.

Comparison of an old-style patch (top) vs. a new-style patch (bottom).

On the first fishing attempt, once we inflated the packer in the pipe, our line indicator identified that it was hooked, and the application engineer for the packer company was so convinced we had it that they left and flew back home.

With the success of retrieving all the pumping equipment, we looked at other opportunities this technology could provide. In further discussions with the packer manufacturer, they explained all the applications that the swage could be used for, including swaging a well using their inflatable packer technology.

Variety of Benefits

To highlight some of the benefits that convinced us of using a pneumatic packer to swage a well versus a hydraulic swage would be the speed at which we can reline a well. As mentioned earlier, the hydraulic swage was slow and cumbersome whereas relining 100 feet with the pneumatic packer took days rather than months to complete.

The hydraulic unit swages about 1 to 2 feet at a time and requires multiple swages to get a 360-degree imperfect seal. This requires the tool to be rotated 60 degrees after each expansion to get a semi-uniform fit. Our inflatable pneumatic packer can swage 5 feet all at a time and only requires one expansion providing for a perfect 360-degree cylindrical compression fit to the casing surface.

Additionally, the amount of control, precision, and the ability to use clean clear water versus hydraulic oil in potable water wells are additional reasons the pneumatic inflatable packer is superior to the hydraulic swage.

Some of the creative ways we’ve been able to expand on the capabilities of our pneumatic inflatable packer are utilizing it to correct water quality, bridging caving zones, fishing, welding the Schedule 10 stainless steel patches together radially, and repairing compromised casing to give our clients’ wells a new lease on life.

What follows are a few overviews of jobs our company has performed utilizing our pneumatic inflatable packer to overcome complex issues for our clients.

Example 1: We were contacted by a dairy in central Wisconsin that was experiencing a well with dirty shale water that was unable to be used for livestock and human consumption. Upon removing the pumping equipment and looking at video of the well, we discovered it was constructed with the casing falling just short of a cavern and fragile shale zone. The shale and formation was caving, blocking the lower borehole, and producing dirty water.

We took three 6-inch × 20-foot sections and one 6-inch × 5-foot section of Schedule 10 stainless steel and radially welded them together to create one long string that we could swage out to the ID of the 8-inch casing and open borehole from 5 feet into the casing, through the shale and cavern, and to the competent limestone below. The result was a perfectly cylindrical extension of the existing casing that ultimately halted the caving formation and production of dirty water.

Example 2: A municipality in northwestern Wisconsin contacted us after another contractor had discovered compromised casing at the weld joint between the well casing and screen that was allowing gravel pack to enter the well.

The contractor on site suggested the installation of a grouted liner, but the owner had heard about our swaging technologies through a recent trade show and contacted us. We were able to install an 18-inch × 20-foot Schedule 10 stainless steel patch from 3 inches into the screen extending upwards into the 20-inch casing. This ultimately stopped the introduction of gravel pack into the screen that could have been sucked into the pump, damaging the equipment or ending up in the distribution system.

This approach was able to be performed in one day in a cost-effective manner versus the weeks it would have taken to install a grouted liner at a much higher cost.

Example 3: A community in the Greater Milwaukee area was working with another contractor who was unable to provide a solution to their greatly deteriorated casing over multiple service cycles. The contractor told the municipality there was no saving the well and that their hydraulic swage technology would not be a solution to patching the casing due to the need to install them in 5-foot sections and having no competent
casing left from depths of 105 feet down to 155 feet.

The municipality contacted our company, seeking a second opinion. When we mobilized, removed the pumping equipment, and performed a video survey, we were shocked at the gaping holes in the casing, but we did not think it was unrepairable with our pneumatic inflatable packer.

We proposed installing 155 feet of continuously welded 6-inch Schedule 10 stainless steel and swaging it out, starting at the surface in the competent casing and continuing down to the bottom of the casing at 155 feet—an installation that had never been performed before.

The installation was successful and effectively relined the entire well casing, giving it a new lease on life. This installation not only allowed the city to still use its original pumping equipment without needing to downsize it as you would with a traditional grouted in-place liner but also saved the city millions of dollars in not having to drill a new well.

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Our company is still finding cost-effective and innovative ways to expand on the original intention of the pneumatic inflatable packer to provide solutions to complex water well issues across the United States 10 years later. As we’ve grown and developed the technology, we’ve successfully implemented it in Florida, Georgia, Illinois, Indiana, Iowa, Kansas, Michigan, Missouri, and Wisconsin.

Todd E. Kerry is a third-generation water well professional and currently vice president and partner at Water Well Solutions Illinois LLC where he has worked in the groundwater industry for 30 years. He is a licensed water well and pump contractor in both Illinois and Wisconsin as well as a certified water operator in Illinois. Water Well Solutions Illinois and Water Well Solutions Wisconsin are subsidiaries of the Sylmar Group which also owns General Pump Co. in California. Kerry can be reached at todd.kerry@wwssg.com.

Philip M. Judkins is a second-generation water well professional and is currently vice president of Water Well Solutions Wisconsin. He joined the company in 2021. He is also a licensed pump installer in Wisconsin. He can be reached at philip.judkins@wwssg.com.