TB Wood's Dura-Flex Coupling User manual
Dura-Flex®Couplings
Installation Instructions
P-7891-TBW
2TB Wood’s • 888-829-6637 P-7891-TBW
Lock out / tag out the power
source before proceeding to avoid unexpected
starts. Failure to observe these precautions could
result in bodily injury.
Coupling element may be thrown
from the assembly with substantial force if
subjected to a severe shock load.
Check operating speed against
Maximum RPM value in Table 1.
For a basic installation overview, scan the QR code
below:
Further component information available:
Specification sheets, 3D models
ecatalog.TBWoods.com
Coupling Selection Program
www.TBWoods.com/Select
Installation / Alignment
Installation / Alignment Tools
• Hex key set
• Socket set
• Torque wrench
• Straight-edge
• Caliper
• Feeler gauge set
1. Inspect all coupling components and remove
any protective coatings, lubricants, paint or
rust from bores, mating surfaces and fasteners.
Remove any existing burrs, etc. from the shafts.
2. Slide one hub onto each shaft using keys where
required. (When using QD or Taper-Lock hubs,
follow the instructions furnished with the Sure-
Grip or Taper-Lock bushings.)
3. When high speed rings are to be used for
spacer couplings, loosely install one ring on
each half element.
4. Hold one half element on the hubs to determine
the appropriate hub spacing. If using spacer
elements with high speed rings, hold both half
elements on hubs to make sure that the hubs
do not interfere with the rings. The hub may be
installed with the hub extension facing in or out.
Make sure that the shaft extends into the hubs
at least .8 times the shaft diameter.
5. Lightly fasten hubs to shafts to prevent them
from moving during alignment.
6. Angular Alignment: Without rotating the
coupling, run a caliper around the hub and
set the caliper to the widest point. Find the
narrowest point with the caliper and feeler
gauges. Reposition equipment until this value
is as small as possible; reference Table 2 for
maximum value/degree.
7. Parallel Alignment: Using the misalignment
value from the previous step, look up the
maximum allowable parallel misalignment using
Table 2 and Figure 1. Without rotating the
shafts, run a straight-edge around the hub and
find the maximum offset with feeler gauges. If
necessary, realign the shafts. Recheck parallel
alignment.
Parallel Alignment
Angular Alignment
Scan to Watch Installation Video
or visit our Dura-Flex product page
at www.TBWoods.com
TB Wood’s • 888-829-6637 P-7891-TBW 3
8. Tighten motor and driven equipment fasteners
to manufacturer specifications; recheck parallel
and angular alignment.
9. When parallel and angular alignment values are
within service ratings, verify that all set screws,
cap screws and other fasteners are tightened to
values in Table 1. Recheck parallel and angular
alignment after tightening.
10. Install coupling guard per applicable safety
regulations.
11. Periodically check alignment, as settling will
often change equipment position.
4º
3º
2º
1º
0
1/32” 1/16” 3/32” 1/8”
0.8mm 1.6mm 2.4mm 3.2mm
Sizes 2-10
Sizes 20-50
Sizes 60-80
Angular
Parallel
Figure 1 - Parallel Gap
Typical Standard Typical Spacer
*Maximum spacer element RPM = Maximum standard element RPM if using high speed rings. HS rings come standard with
sizes 2-10 and are available as an option for sizes 20-80.
**Metric elements and hubs use metric hardware and are denoted by “M” in the part number, e.g. WE2M, WES2M, WE2HM28MM.
Table 1 - Maximum RPM and Fastener Torque Values
Coupling Size
Maximum RPM
Element & Ring Cap Screws BTS Hubs Set Screws
Imperial Elements Metric Elements** Imperial Hubs Metric Hubs**
Standard Spacer*
(HS Rings)
Screw
Size ft-lb Screw
Size Nm Screw
Size ft-lb Scew
Size Nm
WE2/WES2
7500 7500 1/4-20 17 M6-1 23
1/4-20 7 M6-1 6
WE3/WES3
WE4/WES4 5/16-18 14
M8-1.25 19
WE5/WES5 3/8-16 23
WE10/WES10
WE20/WES20 6600 4800(6600)
3/8-16 30 M10-1.5 40
1/2-13 50
M10-1.5 32
WE30/WES30 5800 4200(5800)
WE40/WES40 5000 3600(5000) 5/8-11 100
WE50/WES50 4200 3100(4200)
WE60/WES60 3800 2800(3800)
1/2-13 75 M12-1.75 100 3/4-10 167 M12-1.75 54WE70/WES70 3600 2600(3600)
WE80/WES80 2000 1800(2000)
Table 2 - Angular Inch Gap
Hub Size Degrees
1º 2º 3º 4º
WE2 in 0.03 0.07 0.10 0.13
mm 0.8 1.7 2.5 3.3
WE3 in 0.04 0.08 0.12 0.16
mm 1.0 2.1 3.1 4.1
WE4 in 0.05 0.09 0.14 0.18
mm 1.1 2.3 3.5 4.6
WE5 in 0.06 0.11 0.16 0.22
mm 1.4 2.8 4.2 5.5
WE10 in 0.06 0.13 0.19 0.22
mm 1.6 3.2 4.9 5.5
WE20 in 0.08 0.16 0.23
mm 2.0 4.0 5.9
WE30 in 0.10 0.19 0.28
mm 2.4 4.8 7.2
WE40 in 0.12 0.23 0.35
mm 2.9 5.9 8.8
WE50 in 0.14 0.28 0.43
mm 3.6 7.2 10.8
WE60 in 0.15 0.31
mm 3.9 7.7
WE70 in 0.16 0.32
mm 4.1 8.2
WE80 in 0.20 0.39
mm 5.0 10.0
P-7891-TBW 10/17
www.tbwoods.com
2000 Clovis Barker Road
San Marcos, TX 78666
512-353-4000
