Rani Engineering is a small Minneapolis firm that doesn't act like one, working on huge projects like the Central Corridor light-rail line and tapping North Dakota's oil boom to fuel growth.

Driving the company's expansion, founder and president Susan Park Rani said, are partnerships with bigger firms, rail-signal design services and continuing investments in employees and equipment.

As a woman and minority in a traditionally male-dominated industry, the South Korea-born Rani has seen her profile rise along with her firm's. In July, Gov. Mark Dayton appointed her to the eight-member board overseeing the Mayo Clinic's $5.6 billion Destination Medical Center expansion in Rochester, the largest economic development project in state history. Rani will be the keynote speaker on March 11 at a Rochester Area Chamber of Commerce event focusing on the Mayo project.

"I thought he made a mistake when he called," said the self-deprecating Rani. She was among those accompanying Dayton on his 2011 trade mission to South Korea. Rani left there as a youngster, joining her engineer father here and later earning a civil engineering degree and an MBA from the University of Minnesota.

Rani Engineering has 50 employees and last year topped $4.2 million in revenue, up from a staff of eight and $900,000 in revenue in 2006. Private work accounts for roughly half the firm's business, up from 20 percent in 2006 when government contracts dominated.

'Work for success'

She sees plenty of room to grow. The next-largest firms that offer her core services of civil engineering, land surveying and rail-signal engineering have 9,000 and 52,000 employees. "I always tell our people, 'Some dream of success; we come to work every day and work for success,' '' Rani said.

Rani Engineering, founded in 1993, enjoys "emerging national recognition" for its rail-signal engineering services, with projects in more than two dozen states, Rani said. The work includes engineering on Positive Train Control (PTC) systems, which Rani describes as hardware and software systems that prevent unsafe movements and, in the event of human error, allow for automatic braking to reduce the potential for train collisions. The U.S. Rail Safety Improvement Act of 2008 requires PTC systems to be in place on all rail routes carrying passengers or hazardous materials by the end of 2015.

Continuing demand for freight and transit work spurred Rani to open offices last year in Los Angeles and in 2012 in Dickinson — in the midst of North Dakota's Bakken oil fields. About 70 percent of North Dakota's oil gets to refineries by rail.

Working with U.S. Bank, which recently increased the firm's line of credit, helped ease the move into North Dakota as bankers there advised her on risks to avoid in the new market.

"Susan has a great vision for her company," said Lynn Anderson, a U.S. bank vice president and client manager. "She's great at establishing relationships and trying to make it a win-win."

Rani began offering rail-signal engineering services in 2011 in partnership with an international firm. Land surveying came in 2007, through an alliance with Kimley-Horn and Associates, a St. Paul-based national engineering firm, that led to work on the 11-mile Central Corridor light-rail line. The line opens in June between St. Paul and Minneapolis. Rani Engineering also had surveyors on site throughout the Interstate 35W bridge reconstruction.

'Doesn't act small'

"The best thing to say is they don't act like a small firm," said Charles Hymes, Central Corridor project manager for AECOM, a global architecture, design, engineering and construction services firm. "They're just very responsive. They find a way to get it done."

Rani Engineering faced time and winter weather pressures on its Central Corridor survey work, said Gary Ehret, senior vice president at Kimley-Horn.

"The project is on schedule and the ability to keep it on schedule started to a large degree with their survey work," Ehret said. "I have worked with Susan and Rani going back to their early days. … They should be proud of what they've accomplished."

The expert says: David Oxley, executive director of the American Council of Engineering Companies of Minnesota, said Rani's community involvement and active role in state and national associations, which some larger firms bypass, has boosted her company.

"She has a high level of ambition and has been willing to carry that through in trying to position herself in a way that she can be successful," Oxley said. "It's a difficult business, it's very competitive. In an engineering community that's male-dominated, a female managing to make a successful firm can be [challenging] and she's done well with that."

Todd Nelson is a freelance writer in Woodbury. His e-mail address is todd_nelson@mac.com