Increasing Corrugator Speed – Case Study
Because of today’s increasing pressure on box makers to increase production and reduce costs, it is time to study equipment that is known for increasing corrugator speed capabilities.
Let’s design and build the best infrared drying system for this corrugating unit.
In this case the best system is needed and the OXYTECH SYSTEMS™ talented fabricators are the best choice to design, manufacture and install the custom built infrared drying system for increasing corrugator speed. This system is for a traditional style gas heated corrugating unit. Our test subject is a typical gas fired corrugator that runs consistently up to 500 board feet per minute. This is the absolute top speed for this machine. Greenbond problems start right at 500. To achieve this speed requires a skilled and experienced operator combined with consistent high quality board and glue.
Building the Test Infrared Dryer
To start this test, the OXYTECH SYSTEMS™ team visits, observes and measures the corrugator. They collect information about the specifics of this installation and operation then design, build and install the optimal infrared drying system. Since there are different corrugator situations, it is important to understand the process in order to design the optimal infrared energy source for the corrugator/double-backer. The plan is to evaporate the water out of the glue/starch faster and more consistently.
This new drying unit consists of optimal high-quality infrared lamps. Specially-made reflective panels reflect the energy from the IR Lamps towards the board. The solid state controller with a nice touch screen control box and monitor make the operation work great.
Testing Day
Today is the day to try it out. Because we are utilizing the same operator, glue/starch and board materials the corrugator speed ran up to 500 board feet per minute as usual. Then, when the Infrared Drying System is turned on, we quickly discover that the speed could increase all the way to 700 board feet per minute without greenbond, warping, blistering or washboarding issues.
Dramatic Corrugator Speed Increase
In the past, 500 bfpm was the absolute maximum speed this corrugator unit could achieve without greenbond or other problems.
Now, because of the infrared dryer shortening the drying time, the speed of the corrugator zooms right past 500 and up to 700 board feet per minute without incident. The people observing that day witnessed the corrugator speed past 500 board feet per minute and are watching board flying through the corrugator at 700 board feet per minute. This is astounding. Without the infrared dryer the company faces purchasing a new longer corrugator and increasing the gas supply to increase heat transfer. However, using the same corrugator plus the new infrared dryer they will increase corrugator speed up to 40%. Today the corrugator consistently achieves the higher production requirements and simultaneously outputs higher quality board.
What about the Greenbond Concerns?
Greenbond concerns; Some people expect the point of contact between the fluting and the outer layers to be compromised by the speed increase and the reduced drying time. These concerns are completely alleviated as soon as the board is inspected and tested after corrugating. Controlling cross-direction moisture profiles and increasing adhesive solids at the glue line improves greenbond and reduces blistering, board warp and washboarding. It turns out that faster and more consistent evaporation of water from the glue combined with the reduced amount of glue and the increased glue solids at the glue line actually improve the strength of the glued contact point. Greenbond concerns are completely alleviated.
Additional Benefits
The additional benefits of infrared drying:
- Improve consistency of the finished cardboard
- Eliminate board warping and blistering
- Reduce glue consumption per foot of board
- Save energy per foot of board
- Conserving flute and liner material due to reduced waste
- Increase production per man hour.
What Makes This Work?
What makes this possible is the infrared heat penetrating faster and more evenly into the board. This evaporates water from the glue faster and more evenly. Since the glue is drying more evenly, less glue is required. With the reduced quantity of glue being applied, this further reduces the amount of time required under the infrared dryer to dry. The board quality is also improved. The OXYTECH SYSTEMS infrared heating system is a variable heating system which adapts to the corrugator speed and board. This ensures optimal glue and board drying at varying speeds. There was a concern that the reduced amount of glue would degrade the board quality. Surprisingly, in fact, the opposite occurs. The reduced quantity of glue combined with the more consistent drying process results in a better board.
Eliminate Board Blistering
The more evenly distributed heat penetrating the board from the infrared lamps also reduces the or eliminates the occurrence of board blistering. This improves efficiency and overall output in addition to maintaining a higher level of quality and reduced waste.
Eliminate Board Warping
With more evenly distributed heat penetrating the board from the infrared lamps also reduces the or eliminates the board warping. Again, this also improves efficiency and overall output in addition to maintaining a higher level of quality.
Summary
Adding a properly designed infrared drying system will aid the goal of increasing corrugator speed. The speed capability of corrugators will increase by using infrared drying systems to improve the drying process of glue/starch during the corrugating process. The glue/starch will dry faster and more consistently. Corrugator greenbond glue/starch dries by evaporating the water in the glue/starch. Because infrared energy evaporates water from the glue faster and more consistently less glue is needed. The result is that the speed of the corrugating process may be increased by up to 33%. Also, because the process is faster and more controlled, the glue/starch is applied more evenly resulting in reduced glue/starch consumption.
This results in an immediate savings of time, glue and energy.
Infrared drying uses less energy than gas fired heaters and steam. Efficient infrared energy penetrates the cardboard and glue much faster and more evenly than gas heated air or steam. This faster and more even heat penetration contributes directly to faster and more consistent glue application and drying. Also, increasing drying consistency reduces the amount of glue required so that there is less glue to dry – even further reducing the drying time.
Corrugator speeds have increased from 500 bfpm to 700 bfpm because of the installation of the new Infrared Drying System.
General Infrared Drying System Specifications
Infrared Drying System Specifications:
- These OXYTECH SYSTEMS™ infrared systems use 480 v 3 phase power
- Infrared drying can be installed in less than one day
- These systems are suitable for all board including single, double and triple wall.
Improved Board Quality
Controlling cross-direction moisture profiles and increasing adhesive solids at the glue line:
- Reduce Blistering
- Reduce Board Warp
- Reduce Washboarding.