HOUSTON (AP) — National Oilwell Varco Inc. said Tuesday that net income fell 12 percent in the second quarter on higher costs, but acquisitions and strong demand for capital equipment boosted its revenue.

National Oilwell Varco makes equipment for production of oil and natural gas, and in February it paid $2.5 billion to buy Robbins & Myers, which makes pumps and other equipment to control the flow of oil and gas in drilling operations. National Oilwell said orders for rig technology improved and its contract backlog is at record levels.

Net income slipped to $531 million, or $1.24 per share, from $605 million, or $1.42 per share. Excluding one-time items the company earned $1.33 per share. Revenue rose 18 percent, to $5.6 billion. Analysts expected $1.33 per share and $5.43 billion in revenue, according to FactSet.

Revenue from the rig technology business rose 18 percent to $2.83 billion, while petroleum service and supplies revenue fell 2 percent to $1.75 billion. Distribution and transmission revenue grew 66 percent to $1.3 billion on acquisitions the company made last year.

The company landed $3.15 billion in rig technology orders during the quarter, raising its backlog to $13.95 billion.

Shares of National Oilwell Varco fell $2.74, or 3.7 percent, to $68.40