Sheets Unlimited Enhances Corrugated Board Warp Control and Production Efficiency with Valmet IQ Quality Control System
Valmet will supply a Valmet IQ Quality Control System for corrugator to Sheets Unlimited, one of the largest independent corrugated box manufacturers in the Pacific Northwest, located in Washington, USA. The system will address key quality challenges, most notably moisture imbalance, which is the root cause of warp, to improve board quality, production efficiency and overall converting performance.
For independent sheet feeders like Sheets Unlimited who source stock roll from multiple mills, it is critical to ensure consistent quality and efficient production. Variations in paper grades, moisture levels and fibre characteristics create unpredictable warp behaviour that standard corrugator controls cannot fully manage, affecting converting performance, customer satisfaction and material waste.
“We had the opportunity to see Valmet’s warp control solution in operation at another manufacturer in Europe. What stands out is its ability to address the root cause of warp: moisture imbalance. Based on the strong feedback from users and our own evaluation, we are confident in the value it brings to our operations. With this solution, we are well positioned to reduce variability, improve converting performance and deliver products of even higher quality to both our internal and external customers,” said Krist Leland, Director of Manufacturing, Sheets Unlimited.
“With Valmet IQ, the customer will benefit from improved process stability, more uniform product quality and reduced operator workload. The system’s precise moisture and warp measurements, combined with advanced automation, help minimise material waste and improve resource efficiency, while supporting sustainability targets. This project demonstrates how intelligent automation can enable more streamlined operations and enhanced overall performance,” said David Maddux, Board Converting Automation Sales Manager, North America, Automation Solutions, Valmet.
The delivery includes combined paper temperature, moisture balance, total moisture and warp control, utilising an interface to the existing state-of-the-art corrugator heating elements. It also incorporates Valmet’s proven moisture measurement technologies and automatic moisturising solutions.
The order was included in Valmet’s orders received in the second quarter of 2026. The value of the order will not be disclosed. The delivery is scheduled for the fourth quarter of 2026, with commissioning planned for January 2027.
Delivery technical information
The delivery consists of Valmet IQ Warp Measurement, Valmet IQ Moisturizer, Valmet IQ Multipoint Moisture and Microwave moisture measurement, integrated with automatic closed-loop controls.
Valmet IQ Quality Control System for corrugator combines online moisture, temperature and warp measurements. It is used to control all corrugated board types to reduce sheet warping, improve bonding and thus maximise corrugated board box plant performance.
About Sheets Unlimited
Sheets Unlimited, headquartered in Renton, Washington, USA, is one of the leading producers of custom corrugated sheets and litho-laminated products for the corrugated packaging and converting industries. Founded in 1985, the company focuses on high-quality, tailored solutions and serves customers with a wide range of packaging needs across industrial applications.
