COMPUTERIZED CROWNER RETROFITS
product line was developed in 1987 with the first unit sold to then Reynolds
Metals Company in Listerhill, AL for installation on a 44" Farrel grinder.
Since this time, RGB Engineering has built 40 crowner retrofits which are
installed on all types of roll grinders (traveling carriage and traveling
table), and on many different makes and models - Farrel, Cincinnati, Landis,
Mesta, Lobdell, Churchill, and Norton. Click on the "Customer Reference
List" below for a detailed listing of all the crowner retrofit installations.
A complete description of the basic system, including principles of operation,
hardware, and software, as well as information on boxing & shipping, bench
testing, and instruction manuals, can be accessed by clicking "General
Description". Separate sections are included for specific discussions of
"Accuracy Checks", the profile generation techniques ("FFP Profiles"), and the
very important "Bed Correction Feature". Under "Options", information can
be accessed on additional enhancements like taper control, precision infeed,
load control, the satellite work station, and coarse infeed. Click on
"Installation Examples" for descriptions and photos of some of the
representative installations on various types of roll grinders.
to justify the upgrading to this type of crown control include:
The roll crown and
concave shape profiles should be more accurate than those being produced with a
mechanical crowning device, which is subject to wear and inaccuracies due to the
age of the mechanical components.
shapes (like CVC profiles) and empirical curves can be ground, which are not
possible with a conventional mechanical crowning system.
In addition to the
crowning advantages, the software includes a bed correction feature, which can
compensate for wheel path errors. Corrections can easily be made via the
computer at any future time should tweaking of the alignment be required.
This is very expensive to do the conventional techniques (machining and
precision infeed system is available, which gives the operator the ability to
"infeed" as well as crown using the crown tilt axis, which is not subject to
the backlash and stick-slip limitations of the existing slideway infeed
mechanism common on older roll grinders.
includes an option for "automatic" infeed, which will feed the wheel in
continuously across the roll face at a selected rate, with a step infeed at
the roll ends. This will free up the operator so he does not have to be
a slave to the grinder during the roughing and semi-finishing cycles.
There is also an
optional automatic tripping device, which utilizes the crowner absolute
encoder to interface with the carriage (or table) drive circuit to
provide reversing control to the carriage or table.
The upgrade will
greatly enhance the existing machine's capabilities, and can in fact preclude
the need for a more extensive and expensive rebuild with the resulting loss of
production. There would only be a few days downtime with the crowner
addition of a computerized crowner will allow the grinding of rolls to tolerance
levels consistent with the newer state of the art CNC type roll grinders.
The advantage of this system is that the roll shape accuracy is a function of
the computer, feedback transducer, and servo drive, and to a lesser extent, the
grinder's mechanical components.
Bed Correction Feature
Customer Reference List