An auction process for the 165-year old Scottish company, which makes heat exchangers and gas compressors largely for oil and gas companies, is expected to kick off in the coming days, the sources said.

Colfax is hoping to fetch about 1.5 billion pounds from the sale of the business, which employs more than 5,000 people globally and has operations in 16 countries including Mexico and Canada. It employs 350 people at its main UK site in Renfrew, near Glasgow.

Howden, founded in 1854 and bought by Colfax in 2012, makes core earnings of more than 150 million pounds, two of the sources said, adding the business would mainly appeal to private equity funds due to lacklustre interest amid industry buyers.

Goldman, which declined to comment, is expected to send confidential information to potential bidders this week, one of the sources said.

Colfax was not immediately available for comment.

The sale would cement Colfax's shift from its industrial roots following the $3.15 billion purchase of medical devices maker DJO Global Inc. in November.

Colfax, which has a market value of $2.8 billion, bought DJO - its biggest ever deal - to tap growing demand for medical devices such as knee and hip implants from aging baby boomers.

At the time, it said it would explore options - including a possible sale - for Howden, which in 2017 generated 40 percent of Colfax's total revenue of $3.3 billion.

The change of direction spooked some investors, with Colfax shares tumbling 15 percent on the news.

Colfax's founders – brothers Steven and Mitchell Rales – are familiar with the medical equipment industry as they also launched Danaher Corp, a key player in medical devices, back in 1984. Colfax CEO Matt Trerotola worked at Danaher before joining Colfax in 2015.

(Reporting by Pamela Barbaglia; Editing by Mark Potter)

By Pamela Barbaglia and Arno Schuetze