Eriez ROTA-GRATE Manual

Rota-Grate®and Automated Rota-Grate®Magnetic Separators
Installation, Operation
and Maintenance
Instructions
ERIEZ WORLD HEADQUARTERS: 2200 ASBURY ROAD, ERIE, PA 16506–1402 U.S.A.
WORLD AUTHORITY IN SEPARATION TECHNOLOGIES
SM-221
RotA-gRAte®
& AutomAted
RotA-gRAte®
mAgnetic
sepARAtoRs

2
Introduction
This manual details the proper steps for installing, operating and maintaining
the Eriez Rota-Grate®and Automated Rota-Grate Magnetic Separator.
Careful attention to these requirements will assure the most efficient
and dependable performance of this equipment.
If there are any questions or comments about the manual, please
call Eriez at 814-835-6000 for Rota-Grate assistance.
CAUTION - STRONG MAGNET
This equipment includes one or more extremely powerful magnetic circuits.
The magnetic field may be much stronger than the Earth’s background field
at a distance several times the largest dimension of the equipment.
• If you use a heart pacemaker or similar device you must never
approach the equipment because your device may malfunction in
the magnetic field, with consequences up to and including death.
• To avoid serious pinch‑type injuries caused by objects attracted to the
magnet, keep all steel and iron objects well away from the equipment.
Do not allow hands, fingers, and other body parts to be caught between
the equipment and nearby steel or iron objects.
• Keep credit cards, computer disks, and other magnetic storage
devices away from the equipment because magnetically stored
information may be corrupted by the magnetic field.
• Keep electronic devices, such as computers or monitors, away from
the equipment because exposure to the magnetic field may result in
malfunction or permanent damage to such devices.
Contact Eriez if you have a question regarding these precautions.
CAUTION
Safety labels must be affixed to this product. Should
the safety label(s) be damaged, dislodged or removed,
contact Eriez for replacement.
©2018 ERIEZ MAGNETICS ALL RIGHTS RESERVED

Rota-Grate®and Automated Rota-Grate®Magnetic Separators
3
Table of Contents
ROTA-GRATE®& AUTOMATED ROTA-GRATE®MAGNETIC SEPARATORS
GENERAL DESCRIPTION .................................................................................... 4
INSTALLATION...................................................................................................... 4
GRATE POSITION ........................................................................................... 5
DISCHARGE CHUTE ...................................................................................... 5
PNEUMATIC HOOK-UP.................................................................................. 5
WIRING ........................................................................................................... 5
MOTOR WIRING ............................................................................................. 5
OPERATION .......................................................................................................... 6
CLEANING & MAINTENANCE.............................................................................. 6
REPAIR & ALTERATION........................................................................................ 7
FACTORS THAT AFFECT MAGNET PERFORMANCE ........................................ 7
REPLACEMENT PARTS ....................................................................................... 8

4
General Description
ROTA-GRATE®MAGNETIC SEPARATOR
The Eriez Rota-Grate is designed for materials that
do not flow easily and tend to plug up stationary
grate magnets. The rotating magnetic assembly
prevents material from packing and plugging up
the processing line.
The Eriez Rota-Grate®consists of an arrangement
of 1" (25.4 mm) diameter stainless steel tubes held
in place by two stainless steel end plates. Each
tube contains an assembly of powerful magnets
which, under normal conditions, will retain their
magnetic strength indefinitely.
At the center of each end plate is a shaft hub,
which is bolted to the end plate and keyed to the
shaft. The shaft is provided with shaft extensions
for bearings, and the drive end is provided with
a keyway.
Standard magnet circuits are suitable for
temperatures below 150°F (65°C). Special circuits
are required for higher temperatures depending
upon application criteria. Please review the Eriez
order acknowledgment or contact your local
salesperson if you have questions about the
circuit provided and its temperature limitations.
AUTOMATED ROTA-GRATE®MAGNETIC
SEPARATORS
Automated Rota-Grates are designed for
installations that require frequent cleaning in
vertical closed chutes and ducts. They are also
used for installations in hard-to-reach locations.
The grate has a flanged inlet and outlet for easy
installation. After each batch or after a specified
time setting, the product flow is stopped and the
cleaning cycle is activated.
During the cleaning cycle, the magnet tubes
retract to a position outside the product area.
While the tubes are retracting, the ferrous material
is scraped from the magnets and discharged.
In some models, vibration and/or an air blast
are applied to the retracted magnets to assure
complete removal of the ferrous material. The
magnet tubes then return to the product area
and product flow can resume.
Automated Rota-Grates include a control so the
cleaning cycle can be adjusted. The entire cleaning
operation takes approximately ten seconds.
Installation
ROTA-GRATE®MAGNETIC SEPARATOR
These units may be installed at the discharge
of either open or enclosed chutes, or may be
enclosed within a housing in either an open or
enclosed duct system. They are furnished with
shaft extensions for flange type or pillow block
type bearings and for a driving pulley. When
enclosed within a housing, provision should be
made for a clean–out or port for access to clean
accumulated ferrous contamination from the
magnetic tubes of the Rota-Grate to assure that
all material will pass through the magnetic area.
AUTOMATED ROTA-GRATE®MAGNETIC
SEPARATOR
Use care when uncrating and handling to prevent
damage to the equipment, particularly the
pneumatic drive housing (see Figure 1). Eye bolts
are attached for lifting and for additional support
when mounting the unit.
FIGURE 1
GEARMOTOR
FRONT STOP
TUBEWIPER WALL
BACK STOP
ACCESS PANEL
SCRAP DISCHARGE
CHUTE
PRODUCT
FLOW
ACCESS PANEL
PNEUMATIC
CYLINDERS
16 REVOLUTIONS PER MINUTE
45°
INLET FLANGE
EYE BOLTS
PNEUMATIC DRIVE
HOUSING
OUTLET FLANGE
GEARMOTOR
FRONT STOP
TUBEWIPER WALL
BACK STOP
ACCESS PANEL
SCRAP DISCHARGE
CHUTE
PRODUCT
FLOW
ACCESS PANEL
PNEUMATIC
CYLINDERS
16 REVOLUTIONS PER MINUTE
45°
INLET FLANGE
EYE BOLTS
PNEUMATIC DRIVE
HOUSING
OUTLET FLANGE
GEARMOTOR
FRONT STOP
TUBEWIPER WALL
BACK STOP
ACCESS PANEL
SCRAP DISCHARGE
CHUTE
PRODUCT
FLOW
ACCESS PANEL
PNEUMATIC
CYLINDERS
16 REVOLUTIONS PER MINUTE
45°
INLET FLANGE
EYE BOLTS
PNEUMATIC DRIVE
HOUSING
OUTLET FLANGE
GEARMOTOR
FRONT STOP
TUBEWIPER WALL
BACK STOP
ACCESS PANEL
SCRAP DISCHARGE
CHUTE
PRODUCT
FLOW
ACCESS PANEL
PNEUMATIC
CYLINDERS
16 REVOLUTIONS PER MINUTE
45°
INLET FLANGE
EYE BOLTS
PNEUMATIC DRIVE
HOUSING
OUTLET FLANGE

Rota-Grate®and Automated Rota-Grate®Magnetic Separators
5
Install the magnetic separator in the desired
location in the vertical closed chute or duct.
Installation is intended to be made by a flange
attachment to the inlet and outlet flange of the
grate housing. Hole size and spacing will be
supplied to the customer’s specification, or flanges
will be furnished without holes if none
are specified.
Locate the unit between the flanges of the chute
work, and transfer holes from the flanges of the
chute work onto the flanges of the self cleaning
grate. Install a gasket between each pair of mating
flanges to insure a dust-tight seal.
Grate Position
The Automated Rota-Grate is designed for
installation in vertical or inclined flow systems,
but the unit itself must be installed horizontally,
as shown. For optimum iron separation, a vertical
section at least as high as the dimension listed in
Table 1 should be used above the inlet of the grate
housing (see Figure 2 and Table 1).
The Automated Rota-Grate is designed for a free
falling product. A product shut off valve should be
located upstream from the Rota-Grate to prevent
potentially destructive material backup.
Discharge Chute
Space must be provided so that iron discharge
can fall clear of the discharge chute and not back
up into the unit. Continuation of the 45 degree
discharge chute to a collection point is the most
common method of eliminating this waste.
Pneumatic Hook-Up
An 80 psi (5.3 bar) air supply is required to operate
the pneumatic Automated Rota-Grate. Connect
the air supply to the inlet of the air preparation unit.
Wiring
See Figure 3 for wiring the Eriez Automated
Rota-Grate. Also refer to the electrical outlet and
schematic drawing, 4N-9608105, packed with
the unit.
Connect the two AC leads from the AC power
source to terminals 1 and 2 in the control box.
Make all corresponding connections between the
control box location and the junction box on the Self
Cleaning Rota- Grate, as shown in Figure 3.
Motor Wiring
Connect three-phase power supply so rotation
of the magnet reel corresponds to the direction
arrow on housing.
GRATE SIZE HEIGHT (Y) MINIMUM
IN MM IN MM
12 Dia. x 14 305 x356 14 356
16 Dia. x 18 406 x457 18 457
22 Dia. x 24 559 x610 24 610
TABLE 1
Y
FIGURE 2
FIGURE 3
3 4 5 6 7 8 9 10
3 4 5 6 7 8 9 10
SOL 1A
1LS
SOL 1B
2LS
JUNCTION BOX
CONTROL BOX

6
ROTA-GRATE®MAGNETIC SEPARATOR
The speed of operation should be 30 rpm or less,
depending upon the condition of the material
being processed. A good average speed for best
results is 16.5 rpm.
AUTOMATED ROTA-GRATE®MAGNET
1. Be sure the Automated Rota-Grate is rigidly
attached to mating flanges in the vertical
closed system.
2. Before separating material, turn on the control
box power supply and cycle the unit using the
manual switch. (Allow ten seconds for the unit
to complete the cycle).
3. Continue to cycle three or four times to
become familiar with operating the unit.
4. On the control box, set the automatic cycle
time as desired. Timer unit can be changed to
hours or minutes by removing the timer face and
setting lever on the desired increment. A lever
behind the face will also set the decimal point.
NOTE: For optimum iron separation, cycle the
unit frequently. Cycle times of fifteen minutes
to one hour are standard, but product testing
or observation of magnet loading, through the
product area access door, will help determine
your specific requirement. Fully loaded magnets
will have bands of iron particles that are built
up from 1/8 to 1/4-inch (3 to 6 mm) above the
surface of the tube. Cycle times less than ten
minutes are not recommended. Consider adding
additional units if extremely short cycle times
are required to remove excessive iron buildup.
Operation
Cleaning & Maintenance
WARNING
If your product is abrasive to the point of wearing
through the non–magnetic magnet tubing, magnet
material may enter the product stream. This
exposure could be harmful to the quality of your
product. Examine each magnet tube for wear
during your cleaning operation.
5. Regulator pressure has been preset at the
factory. However, there may be conditions during
material separation (sticky or wet material,
heavy tramp iron load) that will prevent the
magnetic tubes from moving out of product
flow for automatic cleaning. If the Automated
Grate experiences slow operation, adjust the
regulator to increase the air pressure. Increase
air pressure in increments of 10 psi (.7 bar),
until the unit operates fully, without hang-ups.
DO NOT LUBRICATE MAGNET TUBES.
ROTA-GRATE®MAGNETIC SEPARATOR
WARNING
Never attempt to clean the magnets while the
unit is in operation. Bodily injury can occur.
Lockout/Tagout before cleaning.
Cleaning is accomplished by removing
accumulated ferrous material by hand. Should
fine ferrous contamination be involved, the tubes
can be wiped clean by means of a rag or gloved
hand. Care should be taken to prevent dropping
any ferrous particles back into the cleaned material
outlet. It is recommended that the tubes be
cleaned at the top position so that if any ferrous
particles are dropped they may be caught by the
lower magnetic tubes.
Blotting the tube with the sticky side of masking
tape will also aid in fine iron removal.
The necessary frequency of cleaning will be
determined by the amount of ferrous contamination
in the material being processed. The unit should
be cleaned often to prevent an excessive
accumulation of ferrous contamination on the
magnetic tubes, as this will reduce the magnetic
separation efficiency.
Lubricate bearings on a schedule consistent
with other equipment in use with your product
and environment. An NGLI No. 2 lithium-based
grease is recommended. For motor and gear
reducer maintenance, refer to the manufacturer’s
instructions packed with the equipment.

Rota-Grate®and Automated Rota-Grate®Magnetic Separators
7
WARNING
Automated Rota-Grates have pinch points inside
the grate and pneumatic drive housing. There are
moving mechanical parts driven by the cylinders.
Workers must be instructed not to perform
maintenance on this equipment unless it is turned
off and the air supply and electric power are locked
out. Failure to observe this precaution may result
in serious personal injury.
Tube magnets are very strong and will
instantaneously attract to each other, any iron,
steel railing, or beams in the cleaning area. The
tube magnets in the Automated Rota-Grate are
not intended to be removable. However, if removed
from the rotor, the tubes must not be brought
within 12" (300 mm) of any iron or steel structure
or objects. Failure to observe this precaution may
result in property damage, hand crushing or other
serious personal injury.
AUTOMATED ROTA-GRATE®MAGNET
1. For solenoid valves and air preparation unit
maintenance, refer to the manufacturer’s
instructions packed with the shipment.
2. No adjustments should be made on the
pneumatic cylinder take-up or flow valves.
These items have been preset at the factory.
3. If the unit does not complete the cleaning
cycle, check to see if the support channel is
contacting the limit switch on each end of the
stroke (refer to Figure 4). The limit switch arm
can be adjusted Move the limit switch roller arm
on the grooved spline in the direction of the trip
lever or adjust the roller arm length or both.
Minor contact between the support channel
and mechanical safety stop is normal.
4. Unit is automated not self maintaining. Clean
inside the pneumatic drive housing on a regular
schedule, depending upon the environment
and the material processed. It’s important that
no product be allowed to build up (caused by
dusting or material passing through the tube
wipers). Clean magnet tube and product area
buildup as necessary.
1. High Temperature
Standard rare earth magnet circuits should
not be subjected to temperatures in excess of
150°F (65°C). Special circuits are available for
higher temperatures.
2. Direct Current
Welding equipment should not be used on or
in close proximity to Eriez permanent magnet
circuits. Demagnetization can result from this.
3. Moisture
The raw magnet material should not be
exposed to liquids. This would normally only
result from breaching the magnet enclosure.
4. Physical Abuse
The magnet castings are brittle, and when
subjected to repeated abuse such as banging
on a table or dropping on the floor, the castings
may shatter and the tubes may crack. Over
time, abuse will cause the magnetic field will
diminish.
Factors that Affect
Magnet Performance
Alteration or disassembly of the assembly would
disturb a carefully engineered magnetic circuit
which could only be restored by returning the unit
to our factory for rebuilding and recharging.
Repair, alteration or disassembly of this magnetic
equipment in the field without written authorization
and instructions by Eriez nullifies the responsibility
and guarantee of the manufacturer.
Repair & Alteration

8
©2018 Eriez All Rights Reserved
World Authority in Separation Technologies
Headquarters: 2200 Asbury Road, Erie, PA 16506-1402 U.S.A.
Telephone: [phone] • Fax: [phone]
Website: www.eriez.com e-mail: [email protected]
Manufacturing Facilities: AUSTRALIA • BRAZIL • CANADA • CHINA • INDIA • JAPAN • MEXICO • SOUTH AFRICA • UNITED KINGDOM • UNITED STATES
718-AHA-Web ERIEZ MANUFACTURING CO ©2018 PRINTED IN USA
Note: Some safety warning labels or guarding may have been removed before photographing this equipment.
Eriez and Eriez Magnetics are registered trademarks of Eriez Manufacturing Co, Erie, PA
   
Replacement Parts
PNEUMATIC DRIVE HOUSING PRODUCT AREASUPPORT CHANNEL
98 21 10
3
5
6
ITEM DESCRIPTION QUANTITY
1* Tubescraper Disc 1
2* Bearing Strips (UHMW) 2
3* Clutch Plate 1
4 Air Cylinder 2
5 Oil Seal 1
6 Gearmotor 1
7 Exhaust Muffler 2
8 Air Control Valve 1
9 Limit Switch 2
10 Bearing 2
11 Magnetic Tubes Varies - Recommended
2-4 Spares
*Recommended Spare Parts