By Ed Ballard

LONDON--Porvair PLC (PRV.LN), a maker of specialized filters for aviation and industrial applications, Monday posted a 10% higher pretax profit for the 2014 financial year and said it will press on with a capital investment program after investing 5.1 million pounds ($7.65 million) in expanding its production capacity last year.

Pretax profit in the year to Nov. 30 rose to GBP8.4 million from GBP7.6 million. Revenue climbed 23% to GBP104.0 million, with much of the increase reflecting one-off gains from big contracts. Sales gained 11% when such impacts were stripped out along with currency movements. Porvair had net cash of GBP5.3 million at Nov. 30.

"2014 finished well and order books going into 2015 are healthy with the fundamentals of the markets in which we operate looking satisfactory," said Chief Executive Ben Stocks.

Capital spending will be slightly lower next year, but Porvair still expects to spend just short of GBP4 million as it builds a second aluminum filtration plant in Xiaogan, China, and expands facilities in the U.S., Mr. Stocks said in an interview.

Mr. Stocks said Porvair's metals business is resilient to declining commodity prices. In China, for example, investment in aluminum production is currently "quite high" despite low prices, he said, while lower oil prices have been a "net positive," for Porvair, reducing the cost of gas and raw materials.

"All things being equal, provided the general economic situation stays broadly as it is, we will grow this coming year at about the rate we've been growing, around 10%," Mr. Stocks said.

The company also said it secured orders worth $5.5 million with three customers--Posco (005490.SE) of South Korea, Reliance Industries Ltd. (500325.BY) in India, and an undisclosed U.S. customer--to provide replacement filter elements for gasification plants.

Shares traded 13 pence or 4.5% higher at 303 pence at 0807 GMT.

Write to Ed Ballard at ed.ballard@wsj.com

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