Despite solid earnings released last week, Ameron International Corp.’s stock has been on a wild ride so much so that the New York Stock Exchange has requested an explanation for it.

Shares of the Pasadena-based manufacturer of performance coatings, fiberglass-composite pipe and other infrastructure products saw its stock surge 20 percent at the end of March to a high of $76, only to drop nearly $8 a share and settle around $68 near week’s end.

That movement prompted the New York Stock Exchange to issue a statement requesting “that the company issue a public statement indicating whether there are any corporate developments which may explain the unusual activity.”

The company has not responded to the request and did not answer telephone calls for comment.

The company reported net income of $3.6 million (41 cents per share) for the quarter ended March 5, compared with $481,000 (6 cents per share) for the same period a year ago. Revenue increased 26 percent to $175.3 million from $138.8 million.

According to the company’s quarterly 10-Q filing with the Securities and Exchange Commission, the company benefited from a surge in its composite pipe business, fueled by increased demand for piping in the U.S., Europe and Asia because of rising oil and steel piping prices.

Infrastructure products also increased more than 30 percent in the quarter because of the continuing strength of the U.S. housing market and increasing demand for concrete and steel poles, the filing stated.

Among other sales drivers: Its performance coating sector saw healthy growth of 17 percent, with the company citing increased volume and pricing as key contributors. The water transmission unit of the $700 million company also experienced higher sales mostly because of a large sewer project in Northern California.

The Los Angeles Times reported that rumors of a takeover or merger may have prompted the movement, but that has not been confirmed.