Sheets Unlimited to Deploy Valmet IQ System for Corrugated Board Warp Control

Valmet will supply Sheets Unlimited, one of the largest independent corrugated box manufacturers in the Pacific Northwest, with a Valmet IQ Quality Control System for corrugator operations. The system is intended to address moisture imbalance, identified as a root cause of corrugated board warp, while improving board quality, production efficiency and converting performance.

Sheets Unlimited sources roll stock from multiple paper mills, exposing its operations to variations in paper grades, moisture levels and fiber characteristics. According to Valmet, these variations can contribute to unpredictable warp behavior that standard corrugator controls cannot fully manage, affecting converting performance and material waste.

The delivery will combine paper temperature, moisture balance, total moisture and warp control, interfacing with the company’s existing corrugator heating elements. It will also include Valmet’s moisture measurement technologies and an automatic moisturizing solution. The system consists of Valmet IQ Warp Measurement, Valmet IQ Moisturizer, Valmet IQ Multipoint Moisture and microwave moisture measurement, integrated with automatic closed-loop controls.

Krist Leland, director of manufacturing at Sheets Unlimited, said the company evaluated the warp control solution after seeing it operating at another manufacturer in Europe. He said the company expects the system to reduce variability, improve converting performance and support higher-quality products.

The order was recorded in Valmet’s second-quarter 2026 orders received. Its value was not disclosed. Delivery is scheduled for the fourth quarter of 2026, with commissioning planned for January 2027.

Sheets Unlimited, headquartered in Renton, Washington, was founded in 1985 and produces custom corrugated sheets and litho-laminated products for the corrugated packaging and converting industries.