A former chairman of the Entrepreneurial Exchange, Bob Keiller makes a surprising admission: "The thing is I'm not sure I would consider myself an entrepreneur," says the engineering veteran who runs Wood Group, the oil services firm that is one of Scotland's biggest companies.

The comment seems especially odd as Mr Keiller is speaking in a meeting room at Gleneagles shortly after attending the Entrepreneurial Exchange's general meeting at the Perthshire hotel.

He adds: "You take a look at the guys that start up new businesses; they're out there and they're building things from nothing and creating employment and jobs and then they do it again and I'm not sure that I put myself into that. I'm just a guy that does business, who runs teams and manages people."

The 49-year-old hails fantastic business creators who have been mentors, including Sir Tom Hunter, Sir Bill Gammell and Stewart Milne.

The entrepreneurs in question may disagree with the self-deprecatory view of Mr Keiller, who demonstrated an entrepreneur's instincts while growing up in the Borders, by developing and selling a paper round.

The adult Mr Keiller achieved renown for the pivotal role he played in developing the Aberdeen-based PSN operation from an unloved part of the Halliburton empire into one of Scotland's biggest oil services firms.

Four and a half years after leading a £150 million buyout of the business from Halliburton, Mr Keiller sold it to Wood Group for around £630m in December 2010. Combining PSN and Wood Group created one of the biggest players in the market for providing the maintenance and operations support that helps oil and gas firms maximise output in areas such as the North Sea. Aberdeen-based Wood Group also has a big engineering arm that works on developing new oil and gas assets, and a gas turbines support business.

After backing the buyout of PSN, Sir Tom Hunter's West Coast Capital made a fortune from the sale.

Reflecting on the MBO, Mr Keiller says he saw real potential to develop a business, which did not sit well alongside other parts of Halliburton. But a major factor prompting him to take the risks involved was not wanting to be left with regrets about missed opportunities.

"I did not want to be the guy sitting 10 years hence and saying, 'you know what, you should have done it'. I would rather regret what I do than what I don't do."

Following the deal with Wood Group, which valued his stake in PSN at around £40m, Mr Keiller says a major feeling was one of relief. He took on big personal debts to help fund the buyout.

"When it came to selling there were mixed feelings. It was the end of a chapter but I had a sense of relief we had achieved our aim. On a personal level I did not want the big overhang of debt that could have come back. To an extent it was a sense of phew."

The father-of-three still lives in the house in Aberdeen he bought 20 years ago when working offshore with Amerada Hess.

A move is on the cards though. Mr Keiller is in the process of building a house with wife Lorraine, a midwife whom he met while studying engineering at Heriot-Watt University in the 1980s. He wants the new home to include lots of space in which he can make the mess that his love of painting can involve.

As a young man, Mr Keiller thought seriously about going to art college before deciding to go into engineering. Asked if he has any regrets about the choice he made, he says: "Do I regret it? I would have to say no. It was through my engineering course at university that I ended up meeting my wife. Since then we have had three fantastic children – that has been the centre of my life. I can't regret that."

Two and a half years after the sale of PSN to Wood Group he is very happy with the outcome.

The sale followed months of negotiations, which started over a dinner in Aberdeen's Cults Hotel with Wood Group's then chief executive, Allister Langlands. The talks focused on what would happen after the deal, rather than financials.

The management team, led by Mr Keiller, would only consider bids from firms with cultures that would be compatible with PSN's. He ended one conversation with representatives of a potential bidder before the parties finished their opening cup of coffee.

The team at PSN was also keen it remain a Scottish or UK business. The integration of the two firms has gone well and in November Mr Keiller succeeded Mr Langlands as chief executive.

He praises both Mr Langlands and Sir Ian Wood, who stood down in November after 45 years on the board of a firm he developed from a fishing business.

"I would not pretend to be close to the level of performance Sir Ian and Allister achieved," he said.

Since taking charge, Mr Keiller has focused on four key areas. He has broadened the leadership team and encouraged greater collaboration between different areas of the group, which has operations around the world.

Mr Keiller speaks with real passion about another key area of focus: values. From January, the whole group adopted a common set of values, which prescribes things such as a zero tolerance approach to bribery.

The interest in values doesn't entail people wearing kid gloves: "As part of our people core value we talk about treating people with respect, fairness, openness, honesty and avoiding bullying. You can't be treating people with respect and be a bully so we have had to fire people because, ultimately, their style was incompatible with the core value that demands that we show each other respect."

Mr Keiller adds: "The more senior it is the more problematic it is."

Wood Group is in discussions with one or two people about having to change their style of operations, says Mr Keiller.

He believes the policy has been instrumental in the group winning some contracts and in recruiting and retaining skilled people in a very competitive market.

The rugby fan's fourth area of focus has been communications and ensuring all employees feel they are well-informed members of the same team. He has replied personally to more than 1000 e-mails from employees since taking charge.

Mr Keiller admits he felt a bit nervous about taking on the responsibilities involved in running Wood Group, which achieved rapid growth in recent years under his predecessors, amid strong global demand.

As chairman, Mr Langlands provides active mentorship.

Mr Keiller believes Wood Group is well positioned for growth in markets that are likely to stay strong. Asked if big changes may be on the agenda, however, he says: "There are a number of things I would rather talk about when they are done."

While aiming high in business, Mr Keiller expects to keep his feet on the ground. "My wife keeps me well and truly grounded... and if my PA Shona hears me saying anything pretentious she prints it out and puts it up on a notice board."