ETUNIFORM™ Holders
ETUNIFORM blade holders provide many advantages over rigid holders and conventional conforming holders:
- Uniform blade-to-roll contact pressure
- Minimum possible loading pressure
- Efficient doctoring (good sheet peeling and roll cleaning action)
- Prolonged doctor blade life
- Prolonged roll life
- High quality doctoring at moderate maintenance and operating costs
- Available for virtually all machine positions
- Can be used with new doctors or usually can be retrofitted tupgrade existing doctors
- Tube loading design is usable with air or fluid for even loading
In operation, the control panel channels compressed air to the load tube. This pressure is transmitted directly to the pressure plate assembly, which uniformly loads the blade.
To unload the doctor and lift the blade, the control panel 4-way valve lever is rotated to feed air to the unload tube while the load tube is depressurized. This allows the blade to freely lift away from the roll surface for easy blade changes without damaging roll surfaces.
Operation is cleaner when light pressure is used in the unload tube permitting the tube to act as a seal along the under-surface of the pressure plate. Also, the fingerless design eliminates spaces for dirt to enter.
Holders can be operated on air or fluid, which acts to dampen potential vibration from external sources.
Applications and Loading
Rugged, stainless steel construction makes the Essco ETUniform holder suitable for difficult locations including:
- Fourdrinier Rolls
- Press Rolls
- Dryers and Sweat Dryers
- MG Yankees (see the ETU-Oracrepe for creping Yankee applications)
- Calenders and Reel Drums
KF-35A Blade Holder
Design and Features
Rugged, effective, and simple, Essco's KF-35A blade holder is a widely accepted industry standard for rigid type holders. The KF-35A is made of 316 stainless steel and designed to allow either end or front removal of blade. For ease of blade changing, front removal cutouts can be provided in the holder for applications where the machine frame precludes removing the blade from the aisle. However, end removal should be used wherever possible.
A key feature of this holder is the nylock micro-adjusting setscrews located behind the mounting bolts, usually on 3" centers. These adjusting screws provide a means of moving the blade tip up to 5/32" for profiling of the blade-to-roll fit. This allows blades to be easily aligned at installation or re-aligned after a roll change, roll crown change, or minor bump to the doctor. Stainless steel construction offers a durable, corrosion resistant holder that is generally a better economic choice than mild steel.
Blade Recommendations
The KF-35A holder accepts blades of virtually all thicknesses and materials — from .010" thick metal blades through .250" thick plastic blades. Standard blade width is 3" though other widths can be used for special purposes. Consult Essco to match the best blade to your specific application.
Applications
KF-35A holders can be effectively used in fourdrinier, press, dryer, calender, reel and off-machine applications, and can be custom modified for special purposes. Essco supplies stainless steel filler strips when adapting a type KF-35A blade holder tan existing doctor having an older style holder with a shorter mounting surface.
RJG III™ Blade Holder
Design
The RJG III™ holder is a rigid holder, ruggedly made with a 316 stainless steel top plate, and a series of open style, 316 cast stainless steel, release-coated, bottom blade retainers on 3" centers. The holder is designed to accommodate either end or front removal of the blade. Adjusting screws on the back of the holder allow easy adjustment and precise blade to roll fit.
Key Features
A significant benefit of the RJG III holder arises from the open design. With open blade retainers there is little surface area for foreign particles (fibers, starch, glue, stickies, etc.) to lodge solidly in the holder. Moving the blade laterally only 1" will dislodge particles which can then drop free of the holder. Consequently, the tendency for the blade to become packed into the holder is minimized and blade removal is easier. The segmented retainers also make cleaning the holder throat simpler. The RJG III holder is ideal for new applications, or is interchangeable with KF-35A style holders on existing doctors as it uses the same mounting bolt pattern. Stainless steel construction eliminates corrosion as a contributing cause of blades becoming stuck in the holder. The release-coated retainers further ease blade changes. Pricing is very economical.
Doctor Blade Recommendations
Blade design is with either punched tabs or rivets only (no clips) to minimize places for stickies to build-up on the blade. Blades are held securely in the holder by the bottom retainers. Holder performance is further enhanced when paired with corrosion free blades such as Essco's high performance AC™ carbon fiber, Fiberline™ epoxy fiberglass, stainless steel, or bronze.
Applications
Essco recommends that the RJG III holder be used where lodging and solidification of particles occurs inside conventional blade holder throats. The RJG III holder is ideal for dryer doctor applications on recycled paper, brown paper, fine paper following coaters or size presses, or any position where corrosion or build-up makes conventional holders troublesome to use.
Creping Doctors
Essco supplies creping blades and creping doctors to virtually every North American tissue maker.
Essco's Ora-crepe blade holder provides excellent performance and minimal set-up and maintenance.
Precision engineering and heavy-duty fabrication of all components are a trademark of Essco performance.
ETU-Oracrepe
A heavy-duty self-conforming, pneumatic tube loaded holder for Yankee creping and cleaning doctors. Open construction and cover provide easy clean out. Lifting strip in slots allows use of varying blade widths as blades are re-ground. All stainless steel construction.
Ladder Type
Rigid holder design for Yankee creping, cleaning, and cut-off doctors. "Ladder" slots allow various blade widths. Heavy-duty, all stainless steel construction.
Coater Wash Roll Doctors
Essco’s AQUACLEAN™ doctor system is specifically designed for use on coater backup wash rolls.
Aquaclean doctors can improve runnability, reduce roll maintenance, and improve product quality.
Heavy-duty 316L stainless steel construction with blind-tapped holes and multiple full-length seals prevent cleaning pond leak-through.
The pneumatic seal tube allows your mill to adjust blade flexibility to changing grades by changing blade thickness or the addition of backing blades.
Type Aquaclean
A proprietary Essco design for water wash cleaning doctor on blade coater backup rolls. Fully sealed, special air load tube, with massive construction for long blade life and effective, leak-free cleaning.
Flexform
Essco’s Flexform™ blade holder offers blade conforming performance similar to more expensive ETUniform pneumatic holders. The Flexform holder conforms to the roll profile without the need for cumbersome micro-adjusting screws. This holder has the same dimensions as a KF blade holder, and can be ordered to accept either KF or ETU blades. The segmented blade fingers reduce fiber build-up, reducing blade removal problems. 316 stainless steel construction avoids deformation problems inherent with composite top plates.