Objectives
- Meet production requirements for drying heavy Douglas fir, hemlock, and spruce veneer
- Engineer and deliver the longest veneer dryer in the world without sacrificing reliability or serviceability
- Maximize dryer efficiency and veneer quality
Project Overview
In 2024, Westmill supplied Roseburg Forest Products’ Coquille, Oregon plywood mill with a new six-deck, steam-heated jet veneer dryer measuring 204 feet in total length – the longest veneer dryer ever installed in the world.
The project reflects a longstanding partnership between the two companies. For many years, Westmill has been RFP’s trusted dryer supplier of choice, providing new dryers as well as upgrades to existing equipment.
Application Engineering
During the quoting process, Roseburg provided Westmill with its production goals, including the requirement to dry heavy, moisture-laden Douglas fir, hemlock, and spruce veneer. Westmill used its dryer-sizing program to translate these requirements into the final design: a six-deck dryer with 30 hot sections and 3 cooling sections.
The resulting dryer was engineered to incorporate Westmill’s innovative, proprietary and Patented technologies. The design provides the performance, efficiency, and reliability needed for consistent, high-volume veneer production.
Design Strategy
There were several engineering challenges that had to be addressed because of the dryer’s length and unique design. Westmill’s engineering team worked through these challenges during the design process. Collaborating closely with Roseburg’s’ team, Westmill ensured the dryer met their site-specific needs.
Key Elements Included
- 2PEx™ Exhaust & Humidity Control System
A Patented system providing precise humidity control inside the dryer’s full 180-foot hot section. The result is higher production, lower energy consumption, and higher-quality veneer.
* Roseburg played an important part in the original development of this technology nearly a decade ago. - Dual WestVac™ Seal Sections
Westmill’s Patented WestVac™ systems were installed on both ends of the dryer, sealing in heat and locking out emissions at these two critical points. - Quick-Change Roll Baffle System
Patented baffle design that significantly reduces the time required to change a full set of baffles. - Cog-Belt Fan Drives
All 30 hot-air circulation fans run on clog-belts rather than traditional V-belts, providing positive drive engagement, consistent fan speed, and efficient power transmission.
Challenges & Solutions
Challenge: Engineering thermal movement across an unprecedented length
Solutions: Designed an all-stainless-steel floor and framework together with redesigned expansion-roller support plates to accommodate the thermal expansion of a 204 ft. dryer.
Challenge: Routing steam and condensation piping along the length of the dryer
Solutions: Integrated supports into the dryer design for steam headers and condensate piping, allowing for easy access for servicing and maintenance of steam valves and traps.
Results & Feedback
Roseburg’s feedback since start-up has been positive, with the plant reporting that the new dryer is performing well and that operations are going smoothly.
“We’ve noticed that, by shifting the exhaust to favor the dry end on our 2PEx Exhaust System, we can dramatically increase the overall humidity inside the dryer. It also seems to produce nicer veneer.”
Dryer Operator Feedback – Roseburg FP, Coquille, OR
The Bottom Line
When Roseburg set out to expand drying capacity at its Coquille plywood mill, it turned to a partner it had trusted for more than a decade. Westmill answered with a first-of-its-kind project: the longest veneer dryer ever built in the world, engineered from the ground up to handle Roseburg’s heaviest, wettest veneer species while incorporating the company’s patented WestVac™ Seal System and 2PEx™ humidity -control technology. Delivered ahead of schedule and installed alongside a brand-new building addition, the project reinforced a long customer relationship – and set a new benchmark for what a veneer dryer can do.
“When you buy something from them, you’re not just a commodity. They collaborate with you… They support you, they build good equipment. They’re there for you.”
Duane Hopkins – Roseburg FP, Coquille, OR
