1. Rolling Mill Industry Training:
RM Configurations & Designs
WORLDWIDE LEADER IN BEARINGS AND STEEL

2. WORLDWIDE LEADER IN BEARINGS AND STEEL
Rolling Mill Industry Training Configurations & Designs
Work Roll Bearings
TQO
Thrust Bearings
Back-up Roll Bearings
Cylindrical Roller Bearings (CRB)
TQO
TQIT
Lubrication
Agenda

3. WORLDWIDE LEADER IN BEARINGS AND STEEL
Rolling Mill Industry Training Configurations & Designs
Work Roll

4. WORLDWIDE LEADER IN BEARINGS AND STEEL
Rolling Mill Industry Training Configurations & Designs
TQOW
Work Roll
• Two double cones/ two single/ one
double cup
• Straight bore
• Preadjusted with spacers to achieve
proper setting
• Inner cone spacer piloted & hardened
• Lubrication entries in the cup spacers
• “Direct” style mounting

5. WORLDWIDE LEADER IN BEARINGS AND STEEL
Rolling Mill Industry Training Configurations & Designs
2TDIW
Work Roll
• Two double cones/ four
single cups
• Can be supplied with or
without center spacers
• Can provides tighter
OAW tolerance (822 Code)
• All other properties
similar to TQO

6. WORLDWIDE LEADER IN BEARINGS AND STEEL
Rolling Mill Industry Training Configurations & Designs
Work Roll
Typical Mounting
• Loose fit cones/ cups for
ease of assembly
• Cups must be clamped
• Cones must be unclamped
• Drive Side - Float
• Operator Side - Fixed
(via keepers)
Thrust Ring
Split-hinged
Ring
Threaded
Rings
Fillet
Ring

7. WORLDWIDE LEADER IN BEARINGS AND STEEL
Rolling Mill Industry Training Configurations & Designs
Work Roll
Chock Sealing
• Two seals on inboard side
• One seal on outboard side
• Additional sealing often
used at fillet ring
• Seal orientation is critical
Fillet
Ring
ContaminationBearing
Oil
Grease

8. WORLDWIDE LEADER IN BEARINGS AND STEEL
Rolling Mill Industry Training Configurations & Designs
Work Roll
Sealed Roll Neck Bearings (SRNB)
• Sealed version of standard WR
bearings
• Provides an additional seal
against contaminant ingress &
helps to retain grease
• Designed to have nearly the
same capacity as the unsealed
bearing
• 2TDI Configuration featuring
spiral bore grooves, faces slots
and no center spacers
• Solid or Relube Cup Spacers

9. WORLDWIDE LEADER IN BEARINGS AND STEEL
Rolling Mill Industry Training Configurations & Designs
SRNB Configurations
SRNB’s
SRNB – Seal Configurations

10. WORLDWIDE LEADER IN BEARINGS AND STEEL
Rolling Mill Industry Training Configurations & Designs
Work Roll
Work Roll Bending
• Used to maintain proper profile
(HSM) and flatness (CSM)
• Radial load taken by WR bearings
• Bearing enhancements may be
required
Negative
Positive

11. WORLDWIDE LEADER IN BEARINGS AND STEEL
Rolling Mill Industry Training Configurations & Designs
Work Roll
Axial Roll Shifting
• Alternate method of flatness/ profile
control
• Induces thrust on work rolls
• Requires an external thrust bearing

12. WORLDWIDE LEADER IN BEARINGS AND STEEL
Rolling Mill Industry Training Configurations & Designs
Work Roll
• External thrust bearing
• Takes thrust in both directions
• Inner race keyed to roll neck
• Additional radial clearance
added over cups
• Spring loaded cups
(can be integrated into bearing)
TDIK

13. WORLDWIDE LEADER IN BEARINGS AND STEEL
Rolling Mill Industry Training Configurations & Designs
Work Roll
TTDWK
• Required for high thrust loads
(ex. Structural & Beam mills)
• Takes thrust in each direction
• Spring loaded outer races
• Alternate Double Directional
V-Flat Assembly

14. WORLDWIDE LEADER IN BEARINGS AND STEEL
Rolling Mill Industry Training Configurations & Designs
Back-up Roll

15. WORLDWIDE LEADER IN BEARINGS AND STEEL
Rolling Mill Industry Training Configurations & Designs
TQOW TQITS
Back-up Roll
CRB

16. WORLDWIDE LEADER IN BEARINGS AND STEEL
Rolling Mill Industry Training Configurations & Designs
Back-up Roll
Cold Rolling Mills • Thinner gauge product
(sheet and foil gauges)
• Typically rolled at higher
speeds
• Final product – requires
good flatness/ gauge
control
• Requires improved
bearing/ mill precision

17. WORLDWIDE LEADER IN BEARINGS AND STEEL
Rolling Mill Industry Training Configurations & Designs
4-row CRB - BUR Bearings
Back-up Roll
RY Type RX Type
- Two outer races with triple flanges
- Machined bronze cages
- Bore Range: 6.3” – 13.8” (160 – 350 mm)
- OD Range: 9.0” – 19.6” (230 – 500 mm)
- Two single flange outer races
- Pin type normally used
- Bore Range: 12” – 47” (300 – 1200 mm)
- OD Range: 16.5” – 62.5” (420 – 1590 mm)
- Also offered with tapered ID (RYK, RXK)
- Inner Rings normally customer finished after mounting
- Standard envelope tolerance: P6
- Standard running tolerance: P5

18. WORLDWIDE LEADER IN BEARINGS AND STEEL
Rolling Mill Industry Training Configurations & Designs
Long Products
• Multi-Row Cylindricals (RY Type)
• Angular Contact Ball Bearings
Bar & Tube Mills

19. WORLDWIDE LEADER IN BEARINGS AND STEEL
Rolling Mill Industry Training Configurations & Designs
Back-up Roll
4-row CRB Mounting – Operator Side
Thrust Bearing
- absorbs external thrust
- stabilizes axial roll position
Most popular anti-friction BU Roll bearing…high capacity / high precision capability
Note: Drive side chock may use locator bearing, such as deep groove ball bearing

20. WORLDWIDE LEADER IN BEARINGS AND STEEL
Rolling Mill Industry Training Configurations & Designs
CRB - BUR Bearing Installation
• Outer race and roller assemblies are
loaded into the chock.
• Inner rings are mounted independent of
outer ring/ roller sets.
• Inner rings are mounted with an
interference fit on the roll neck.
• Inner rings can be supplied to finished
“OD” size or can be finish ground on the
roll neck.
Back-up Roll

21. WORLDWIDE LEADER IN BEARINGS AND STEEL
Rolling Mill Industry Training Configurations & Designs
• Minimizes eccentricity of the
Roll Neck to the Roll Body
• Minimizes Inner Race Wall
Section Variation Contribution to
Eccentricity
• Provides Tighter Control of
Bearing Radial Internal
Clearance ( R.I.C. )
• Provides More Consistent
Inner Race OD Size Control ( on
each neck )
Benefits of Finish Grinding Inner Race OD
After Mounting on the Roll Neck
Back-up Roll

22. WORLDWIDE LEADER IN BEARINGS AND STEEL
Rolling Mill Industry Training Configurations & Designs
Installing the Chock Assembly:
• Suggested Mounting Methods:
• Chocking/ Dechocking Machine
• Piloting Sleeve
• Overhead Crane
- Care must be taken when using
a crane to align the chock prior to
installation.
• Regardless of mounting method, care
must be taken not to damage the inner
races during assembly.
Back-up Roll

23. WORLDWIDE LEADER IN BEARINGS AND STEEL
Rolling Mill Industry Training Configurations & Designs
Key Points for CRB Back-Up Roll Bearings:
• Inner Races Stay with Rolls
• Outer Assembly Stay with Chocks
• Chock Assemblies Interchangeable from
Roll to Roll
• Inner Race OD’s Can be “Skin Ground”
to Extend Useful Life in the Mill
(however RIC will be affected)
Back-up Roll

24. WORLDWIDE LEADER IN BEARINGS AND STEEL
Rolling Mill Industry Training Configurations & Designs
TQITS
• Two single, one double
cone / four single cups
• Tapered bore
• Preadjusted with
spacers to achieve
proper setting
• “Indirect” style
mounting
Back-up Roll

25. WORLDWIDE LEADER IN BEARINGS AND STEEL
Rolling Mill Industry Training Configurations & Designs
Back-up Roll
• Tight fit cones/ loose fit cups
• Cones must be clamped
• Float through cups on drive side /
Fix cups on operator side
• Fillet ring length critical to control
fit (Ring Gauge)
• Roll neck taper must match cone
bore taper (Sine Bar)
TQITS Mounting

26. WORLDWIDE LEADER IN BEARINGS AND STEEL
Rolling Mill Industry Training Configurations & Designs
Back-up Roll
• Hydraulic jack used to push
assembly up tight
• Inspection hole suggested to
check for gap between lead cone
& fillet ring
TQITS Mounting Device
Hydraulic Jack

27. WORLDWIDE LEADER IN BEARINGS AND STEEL
Rolling Mill Industry Training Configurations & Designs
Back-up Roll
TQITS Hydraulic Removal
(“Three-Hole System”)

28. WORLDWIDE LEADER IN BEARINGS AND STEEL
Rolling Mill Industry Training Configurations & Designs
Back-up Roll
• Similar to mounting used
for work rolls
• Used for mill speeds less
than 2500 fpm
• Typically used for lower
precision applications
(HSM/ Roughing Mill)
TQOW Configuration and Mounting

29. WORLDWIDE LEADER IN BEARINGS AND STEEL
Rolling Mill Industry Training Configurations & Designs
Back-up Roll
Oil Film BUR Bearings

30. WORLDWIDE LEADER IN BEARINGS AND STEEL
Rolling Mill Industry Training Configurations & Designs
Lubrication
Basic Methods of Lubrication
(for Rolling Mill Applications)
q Grease
q Oil Mist
q Air-Oil
q Circulating Oil

31. WORLDWIDE LEADER IN BEARINGS AND STEEL
Rolling Mill Industry Training Configurations & Designs
q Commonly used for work roll bearing position
q TQO & SRNB’s
q Applicable to BUR bearings in medium and slow speed mills
(<2,500 FPM/250 RPM)
q Venting required
q Grease fill recommendation:
q 30 to 50% of Total Bearing Free Volume
q Suggested grease properties:
q Base Oil Viscosity @ 40C: 320-460 cSt
q Additives: Corrosion and Oxidation Inhibitors, EP Additives
q Petroleum Or Synthetic Oil
Lubrication
Grease

32. WORLDWIDE LEADER IN BEARINGS AND STEEL
Rolling Mill Industry Training Configurations & Designs
q Atomized at Mist Generator and conveyed to nozzles
q Ideal mist velocity: 12-15 ft/s
q Piping sized to achieve desired velocity
q Gravity feed required from mist generator
q Internal Chock Pressure ≈≈≈≈ 0.75 psi
q Venting required for proper distribution of oil
q Oil Viscosity should not exceed 460cSt
q Air and Oil are typically pre-heated
q10% of oil mist may remain airborne (Stray Mist)
Lubrication
Oil Mist

33. WORLDWIDE LEADER IN BEARINGS AND STEEL
Rolling Mill Industry Training Configurations & Designs
Lubrication
q Spray-type nozzles recommended
q No. of holes in nozzles selected based on desired flow (CFM)
q Suggested oil flow rates calculated from:
q CFM = DR/14 (Bearings - Rolling Mill Service)
q CFM = D/40 (Seals)
Oil Mist Nozzles

34. WORLDWIDE LEADER IN BEARINGS AND STEEL
Rolling Mill Industry Training Configurations & Designs
a. oil entries
b. combination vent
and oil level
c. oil drainage
d. combine vent and
oil drainage for inner
seal at bottom dead
center
Lubrication
Oil Mist - Chock Schematic

35. WORLDWIDE LEADER IN BEARINGS AND STEEL
Rolling Mill Industry Training Configurations & Designs
q Oil transported along inside wall of pipe
q Oil distribution cartridges mounted in chock
q Not limited to oil viscosity range
q Chock’s internal pressure (3-5 psi) helps prevent
contaminant ingress
q Oil Consumption is ≈≈≈≈ 25% of an oil mist system
Lubrication
Air-Oil

36. WORLDWIDE LEADER IN BEARINGS AND STEEL
Rolling Mill Industry Training Configurations & Designs
Lubrication
Air-Oil Delivery
OIL FILM
OIL/AIR
STREAM
METERED OIL SUPPLY
(cc/HOUR)
COMPRESSED
AIR

37. WORLDWIDE LEADER IN BEARINGS AND STEEL
Rolling Mill Industry Training Configurations & Designs
Lubrication
Air-Oil Schematic
Mixing
Station
Air Oil
Air-Oil