Proper web handling, achieved with best practices and use of appropriately designed, engineered and manufactured equipment will insure transport of webs through various converting processes without defect.
Most converting processes include several tension zones within one machine. Tension zones fall into one of three categories; unwind, internal and rewind. Web handling equipment is utilized in all tension zones. This equipment includes:
- Tension Controls
- Web guide controls
- Anti-wrinkle systems and devices
- Core holding devices
- Nip roller assemblies
- Unwind equipment
- Rewind equipment
- Shaft holding, securing, leveling and aligning systems and equipment
- Safety chucks
- Shaftless core holding systems
- …. And many more
- Plastic films
- Nonwoven materials
These materials are typically stored and shipped in wound, roll form. Rolls can be as small as a few inches in diameter and as large as many feet in diameter. Material width can vary from a fraction of an inch to many feet wide.
Examples of converting processes are:
- Slitting (making narrow rolls from wide rolls)
- Die cutting (cutting pieces from the web)
These processes can run from very slow speeds; less than one foot per minute to very high speeds; thousands of feet per minute. Processes can include high levels of technology and sophistication. Most processes are somewhat custom in nature.
Material rolls are typically unwound from roll form in a single layer. They are processed and then rewound into roll form for shipping or further processing. This single layer of material is referred to as a “web” as it flows through a machine or process.
Simply put, “converting” means that a roll of material is processed and becomes a roll of something else… it is converted. For example, an unprinted roll of paper becomes a printed roll of paper, a wide roll of film becomes several narrow rolls of film or an uncoated textile becomes adhesive through a coating process. There are countless converting processes, these are just a few examples.
- Anti-wrinkle systems
- Trim and waste conveying
- Trim and waste choppers
- Core holding for unwinding and rewinding
- Core adapters for various core sizes
- Safety Chucks for unwinding and rewinding
- Unwind and rewind modules
- Shaft holders
- Roller assemblies
- Brakes for unwinding
- Heated rollers
- Web accumulators
- Roll handling (turning)