ABERDEEN-based oil services group EnerMech has been bought by a US private equity giant in a deal it is thought was worth around £450 million.

Carlyle has agreed to buy EnerMech from the Lime Rock Partners investment business in a move which signals confidence in the prospects for oil and gas markets.

It comes as the global oil and gas industry emerges from the long downturn that was triggered by the crude price plunge.

Confidence has started to return to the industry following the rally in the crude price since late 2016, amid moves by major exporters to support the market.

EnerMech chief executive Doug Duguid said the firm’s lengthy track record in energy and the renewed confidence in that sector were significant drivers in attracting a heavyweight investor such as Carlyle Group.

Carlyle will make capital available to support further acquisitions to strengthen EnerMech’s services portfolio and geographic presence.

“With the backing of Carlyle Group, which enjoys extensive relationships in the upstream and downstream sectors, we will be focussed on doubling the size of the business in the next five years,” said Mr Duguid.

The deal will cement Mr Duguid’s standing as one of Scotland’s most successful company builders of recent years.

Mr Duguid founded EnerMech in 2008 with the company’s chief financial officer Michael Buchan amid strong conditions in oil and gas markets. The firm won backing from Lime Rock for an expansion strategy which involved acting as a consolidator in what was seen as a fragmented oil services industry.

The downturn triggered by the sharp fall in the oil price from 2014 to early 2016 posed challenges.

Accounts filed last month showed the group’s UK revenues fell to £116 million in 2017 from £128m last time.

UK earnings before interest depreciation and amortisation dropped to £9.9m, from £15m.

The company said its UK business continued to weather the oil and gas downturn in the latest year.

However the downturn also created further opportunities for EnerMech to grow through acquisition.

The company expanded overseas and diversified into providing services such as support for big infrastructure projects in ways that reduced its reliance on the North Sea.

The group grew total sales to £361.4m last year from £263.9m, helped by strong growth in Australia, the US and Africa. Earnings increased by £19.3 million to £43.6 million.

Mr Duguid said the Carlyle deal was positive news for staff and clients. EnerMech employs around 1,000 people in the UK, out of a global total of 3,500.

Mr Duguid will remain with the business along with Mr Buchan.

Marcel van Poecke, head of Carlyle’s International Energy Partners arm, said: ““EnerMech is an attractive, well-positioned international integrated energy, infrastructure and industrial services company, led by a strong team.

“The company has multiple avenues for growth.”