Plant Services, Inc

Plant Services, Inc


Specialty Turnaround Services

Providing specialty mechanical services at refineries requires knowledge, instinct and a drive that outlasts the problem at hand. That’s why some of America’s largest producers count on PSI for turnaround specialty services. We have the personnel, training and equipment on hand to help you with your shutdown and turnaround needs. Put your trust in our capable hands when it comes to line stops, hot taps, portable machining, pipe cutting/beveling, pump base machining, milling, bolt torque and tensioning and line isolation plugs. We move efficiently, solve problems quickly, and get the job done right, time after time.

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HydrostaticTesting/isolation plugs

  • Test open end pipes, pipelines, tubes and pressure vessels
  • Perform flange-to-pipe weld testing
  • Isolate and test pipe connections

PSI crews utilize the latest hydrostatic testing and isolation plugs to thoroughly pressure test your pipes, pipelines and pressure vessels. PSI test plugs are a safe, effective way to isolate and test pipe connections. Isolation plugs are designed to quickly isolate and hydrostatically test weld joints of any welded flange-to-pipe connection as well as isolating pipe ends during cutting, grinding and welding operations.

With PSI, your piping will be reassembled and back online quickly and safely—and you’ll have peace of mind knowing it’s been done right.

Portable Field Machining

In this industry we all know that time is money, and you’ll save both with PSI’s off-the-truck portable field machining services. Our field team can reface flanges, manways and nozzles on coded vessels and piping thanks to their years of experiencing in machining, pipe cutting and beveling.

PSI carries an extensive equipment inventory and also uses machines from Tri-Tool, Hydratight, Climax, Meridian, Wachs and other leading manufacturers.

PSI is the number one choice in field production machining of high-volume, small-size units including alkylation units. Ask us about our work on flanges and vessel manways up to 96” and larger.

Specialty Applications

Counterboring, J bevels, stainless pipe, low-profile and heavy-walled pipe applications aren’t a problem for PSI. We have all the equipment needed to get the project done, and a team that looks forward to the challenge.

Milling Pump Bases

Wherever equipment repair applications involve milling critical mounting surfaces, such as pump bases or pass plates, PSI has trained personnel and precision machines to do the job. We utilize portable, versatile, three-axis milling machining equipment, and with bed sizes of 20, 49 or 78”, we have the right machine to fit your application.

Pipe Cutting/Boring

Whether in our shop or in the field, PSI has the cold cut/bevel machines you need for piping fabrication. We’ll also help you safely remove sections of old piping without the hassles of hot work permits because no heat or flame is generated with our state-of-the-art equipment.

On-Site Maintenance Services

Plant Services, Inc. is ready to be your plant’s go-to maintenance service provider. We have the knowledge, staff and expertise you want in your maintenance partner. No matter the size or scale of the work, PSI is ready to meet your company’s needs.

GripTight® Isolation Plugs

Isolate and monitor potentially explosive vapors during hot work and hydrotest new weld connections with one easy-to-operate tool. Dual-cavity port creates a complete air-free barrier between the seals—safely isolating the hot work from any residual upstream gases. GripTight® Isolation Test Plugs integrate a Double Block and Bleed Test plug with GripTight Grippers, ensuring operational safety and minimizing the risk of blowout /expulsion due to unexpected upstream pressure in the line.


  • Monitors potentially explosive vapors during hot work
  • Minimizes risk of accidental blowout/expulsion due to improper use or unexpected upstream pressure
  • Uses less than a gallon (3.785 liters) of water, reducing wastewater and treatment expenses while facilitating testing in remote areas

GripTight® Test Plugs

GripTight® High Pressure Test Plugs can significantly improve project schedules and budgets by eliminating the need to weld on end caps. Safely test open-end pipes, pipelines, pressure vessels and piping systems at working pressures up to 15,000 PsiG (1,034 BarG). Patented dual-serrated gripper design provides superior performance in high-pressure applications.


  • Patented dual-serrated gripper design provides more gripping points on pipe I.D. surface
  • Uses test pressure to grip more securely—plug cannot be ejected under pressure when properly installed
  • Eliminates weld caps: no welding or cutting required
  • Reduces test times up to 80%
  • Test plug is reusable and compatible with hydrostatic or pneumatic testing

Pop-A-Plug® Tube Plugs

Pop-A-Plug® Tube Plugs are pressure-rated up to 7,000 PsiG (483 BarG) and conform to ASME PCC-2-2015 (Article 3.12) recommended tube plugging repair methods, offering a permanent mechanical solution to safely seal leaking heat exchanger tubes without welding. Installation takes only minutes, providing superior reliability for critical processes. Full material traceability documentation available.


  • Helium leak-tight seal to 1 x 10-10 cc/sec
  • Unique engineered breakaway controls the installation force preventing damage to the tube, tubesheet and surrounding tubes
  • Ideal for use in applications with coated tubes and tubesheet
  • Readily available from stock with 24/7 emergency manufacturing capability
Tom Thayer Picture

Tom Thayer


Thank you for coming to our website. It is my hope that when you put your mouse down and decide to take action for your facility needs, that we’ve given you enough information for you to make PSI your first call for your specialty contracting needs.

I formed PSI to provide a better, more polished product for our customers in the power and petrochemical industries. To provide “old school” service that was based upon a handshake, and where a service company does just that, provide service. Not only provide service, but provide only the best service, with spot-on pricing, punctuality, professionalism and utilizes a “service with a smile” approach. The company, much like myself has modest roots, remains humble in its demeanor and yet is very driven to succeed and be the very best at what we do.

Mike Bosse

Mike Bosse

Lead Technician

Mike has been with PSI since Late 2014, when he moved over to Billings, MT from Chicago to join our work family.

Mike has been working in the petrochemical industry since he was 19 and has developed quite a few specialty skills over the years. Mike’s certified in multiple PSI service lines such as Isolation/Hydros and torqueing and on-stream leak sealing.

“Bosse” as we refer to him, is another part of our very talented and exciting MT crews. Committed, caring and very personable, Mike is a favorite of our customers and is usually asked for by name when they call in for service work. We enjoy seeing Mike’s bright, smiling face every day around here. He just brings joy to everything he does and is a superb member of our Plant Services, Inc. family.

Sean Carney

Sean Carney

National Technical Operations Manager

Sean has over 13 years of specialty contracting experience and has been with PSI for over 10+ years. Sean started in this industry at a very young age, so despite barely being in his 30’s, Sean has collected decades of experience and has earned his right to manage all of PSI’s territory offices. Sean is a life-long Montana native and grew up in the farm fields just outside of Billings right near the PSI corporate office.

Sean has obtained training and certification in just about every service line PSI has to offer. From Leak Sealing to Hot Taps and Line Stops, Sean’s mastery of these services lines is the baseline that provides him the knowledge to lead our offices to provide only the pinnacle of services to our valued customers.

Sean has the unique background in that he apprenticed at PSI while he was in high school. Seeing things literally from the ground up, as well as working his way up with hard work, dedication and a zest for specialty contracting, Sean’s vision for the future of PSI sets us all up for success. Customer service is core to Sean’s beliefs, and he is our cheerleader to our troops that quality customer service is not easy but is worth it every time and is the only service acceptable here at PSI. Give Sean a call and see what he can do for your specialty needs.