Bob & Alec


Triangle Engineering, Inc. (TEI) is a family-owned organization, founded by brothers Bob & Alec Coulstring, Sr. with the aid of their father Alexander Coulstring in 1960.  Combining talents and experience in welding and mechanical engineering, the company has established a national reputation for supplying the welding industry with equipment and consulting for welder testing, welder training, and procedure qualification.

Old Machining Coupons
Not long after its incorporation TEI’s founders identified an industry need for test materials used for welder qualification by various clients.  From the interpretation of various welding code requirements, TEI established standard weld coupons sizes in pipe and plate and began manufacturing them regularly.


Today, after more than 55 years in business, Triangle Engineering, Inc. is in its fourth generation of family ownership.  TEI continues to remain an industry leader in the manufacture of weld coupons for performance qualification and carries a complete line of procedure test materials covering all welding codes.  TEI’s line of destructive test equipment continues to provide its expansive customer base with the means to qualify its welding workforce quickly, accurately and cost effectively.
TEI weld engineering and consulting throughout the years has also proven highly valuable within the industry as related to the application of a wide variety of procedure qualification materials.  In addition, we provide a full range of testing services utilized by many organizations within the industry. We are an AWS QC4 Accredited Test Facility.

TEI Ocean Expolration B&W

Triangle Engineering, Inc. started as a job shop completing work for various industrial clients; such as machining hard facing valve spools, pump shafts and conveyor screws as well as completing higher profile projects like an underwater research buoy for Woods Hole Oceanographic Institute, processing system components for Ocean Spray, and ultra high vacuum systems for NASA and the U.S. Air Force.

old equipment 2a
Through experience gained from consulting and servicing various clients in the power generation industry, TEI realized the urgent demand for reducing the time and cost required to qualify welders using conventional methods, especially on these types of fast paced projects.  To solve this costly problem TEI designed, patented and manufactured destructive test equipment to expedite the removal and bending of weld test specimens in accordance with the ASME, AWS, and other applicable welding codes.

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