Why the Paper and Printing Industry Needs Rotary Joints
The paper and printing industry is one of the most demanding sectors of all. Production lines often operate around the clock and process several hundred meters of material per minute. Even the slightest temperature fluctuations, unplanned downtime, or uneven roll temperatures can significantly impair product quality and result in high costs.
Numerous rotating rolls and cylinders are used to ensure that paper webs are dried, guided, smoothed, or printed evenly. These must be continuously supplied with steam, water, thermal oil, or other media. Rotary joints provide a secure connection between the stationary supply lines and the rotating machine components.
In paper manufacturing in particular, drying cylinders are heated with steam to remove moisture from the paper web in a controlled manner. At the same time, the resulting condensate must be reliably drained. Tasks include supplying steam to drying cylinders, draining condensate, cooling rollers, temperature control of calenders, supplying thermal oil, and water supply.
Typical media
Media TransmissionSteam
The most important heating medium in the paper industry—ensures that the drying cylinders are heated evenly.
Condensate
It must be reliably dissipated to ensure optimal heat transfer.
Thermal Oil & Other Media
Thermal oil for high operating temperatures; as well as coolants, heat transfer oils, compressed air, nitrogen, and specialty process media.
Typical areas of application
Paper Machines
Continuous steam supply and condensate drainage from the drying cylinders.
Drying Cylinder
High temperatures and continuous operation require robust rotary unions.
Calender
Precise temperature control improves smoothness and surface quality.
Cooling rollers
Even cooling prevents warping.
Printing Presses
Temperature-controlled rollers ensure consistent production conditions.
Advantages of High-Quality Rotary Joints
Reliable Media Transmission
High process reliability
Long service life
Low maintenance requirements
High temperature resistance
High pressure resistance
Durable Sealing Systems
Low wear
High Energy Efficiency
Reduced Downtime
Cost-Effective Plant Operation
Selecting the Right Rotary Joint
Typical designs: Single-channel rotary unions for steam, water, or thermal oil applications—multichannel rotary unions for the simultaneous transfer of multiple media.
Requirements: high temperatures, continuous operation, low-leakage operation, corrosion resistance, and high operational reliability.
Selection criteria: Type of fluid, operating temperature, operating pressure, speed, connection sizes, number of fluids, installation configuration, material, sealing materials, and maintenance requirements.
Maintenance and Service Life: Regular inspections, clean media, and adherence to operating parameters minimize wear and tear and increase system availability.
Conclusion
Rotary joints enable the reliable transfer of steam, water, thermal oil, and other media between stationary pipes and rotating rolls or cylinders. They play a crucial role in ensuring product quality, process reliability, and cost-effectiveness in modern paper-making and printing machines.
