Ameron International Corp. on Thursday reported a steep decline in net income for a third straight quarter due to lower demand for its products in the slower economy. The earnings still beat Wall Street expectations.

The Pasadena company makes water transmission lines; fabricated steel products, such as wind towers, and fiberglass-composite pipe for transporting oil, chemicals and corrosive fluids. It reported net income of $5.9 million (65 cents per share) for the third quarter ended Aug. 30, compared with $15 million ($1.63 per share) a year earlier. Revenue fell 23 percent to $131 million.

Analysts surveyed by Thomson Reuters on average expected net income of 59 cents per share on revenue of $143 million.

Ameron said its earnings fell mostly because of lower earnings from Tamco, its 50 percent-owned steel minimill. The plant has been hurt by lower public works and commercial construction spending in its primary markets of California, Arizona and Nevada. Third quarter sales plunged 78 percent.

“On balance, our core operations performed very well during the third quarter considering the continuation of the global economic slowdown and the lack of infrastructure spending,” Chief Executive James S. Marlen said in a statement, noting that even the Tamco year-over-year loss was lower than in the first and second quarters.

Ameron shares were down $1.14, or 1.4 percent, to $80.35 in midday trading on the New York Stock Exchange.