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March 24 (Reuters) - British engineering firm Smiths Group stuck to its full-year outlook as growth in its detection unit, which makes security sensors, offset declines in other areas of its business and boosted first-half profit.
The diversified supplier of hospital equipment, industrial services and sensors to detect explosives, said headline operating profit rose 27 percent to 277 million pounds ($346 million) in the six months ended Jan. 31.
On an underlying basis, profit rose 8 percent.
Headline revenue grew 18 percent to 1.62 billion pounds, Smiths said, adding that it was flat on an underlying basis, in-line with expectations.
Smiths, which has said it was on the lookout for deals, bulked up its detection unit by buying Safran's U.S.-based Morpho Detection business for $710 million last year.
Smiths forecast further sales growth at its detection unit over the second half, although at lower levels than in the first six months, and said that the unit's margins would be moderate due to the current contract mix and investment in new products.
Growth in the detection unit comes at a time when declines hit the company's John Crane unit, which makes mechanical seals and other products for customers such as BP and Chevron , and the medical unit, which makes healthcare equipment.
The company forecast further challenges in some of John Crane's end markets over the second half, but the medical unit's revenue performance is expected to improve in the period.
"Overall, the outlook for 2017 is unchanged," Chief Executive Andy Reynolds Smith said in a statement. ($1 = 0.8014 pounds) (Reporting by Esha Vaish in Bengaluru; Editing by Amrutha Gayathri)