FEG 20 Imperial Series

A flange profile inner and geared outer ring separated by a 3/4" ball set; a constant section height of 2.025" and a standard range of external diameters ranging from 19.9" to 46.87" matching American dimensions, gearing and bolt patterns

ll QCB® slewing rings are manufactured to the highest possible quality levels in ISO certified factories. A QCB® Quality Standard defines all aspects of their dimensions and tolerances as well as all aspects of manufacturing from materials properties, all stages of production, as well as packing and labelling.

Whilst the data on the site is updated regularly, we reserve the right to implement subtle changes to these standards in our quest for continual product improvement.


While a flange reduces the overall weight of the bearing, it also reduces its torsional rigidity and these bearings are thus best suited to light or medium duty applications where there is not a high load eccentricity.

  • Industrial positioners (e.g. welding assemblies and jigs)
  • Ship or truck loading chutes and swivels
  • Stretch wrapping machines
  • Conveyors and other materials handling equipment
  • Simple amusement rides

If the IMPERIAL sizes and bolt patterns are not quite right, consider the FEG20 Metric Series

Need help?

Our technical team have many years of experience and are happy to assist with selection. Call or e-mail them for fast, efficient and professional advice.

The Design Form will assist you in defining your application details.

QCB referenceOutline dimensions & weight



FEG 506 20 61 AA LM19.90011.97016.22016.14014.4901 72
FEG 639 20 61 AA LM25.15017.09021.34021.26019.6102 96
FEG 740 20 61 AA LM29.15021.03025.28025.20023.5503 115
FEG 836 20 61 AA LM32.90024.97029.22029.14027.4904 128
FEG 945 20 61 AA LM37.20028.90033.15033.07031.4205 152
FEG 1047 20 61 AA LM41.20032.84037.09037.01035.3606 172
FEG 1190 20 61 AA LM46.86738.75043.00042.92041.2707 189
QCB referenceOuter holesInner holes20o spur gear
LanaLiniPDPzFz MAX
in lb.f
FEG 506 20 61 AA LM18.000813.1301219.5004787095
FEG 639 20 61 AA LM23.2501218.1301524.7504997095
FEG 740 20 61 AA LM27.2501522.1301828.75041157095
FEG 836 20 61 AA LM31.0001826.1301832.50041307095
FEG 945 20 61 AA LM35.0001830.0001836.66731109450
FEG 1047 20 61 AA LM38.8801834.0002040.66731229450
FEG 1190 20 61 AA LM44.6302039.8802446.33331399450
Standard grease fitting# at least 2x 1/4"-28 UNF 2B on inner ring

Interchange information

The FEG20 Imperial Series is interchangeable with bearings from other manufacturers such as Rotek, Kaydon, AVON, Silverthin . However there may be variations to this rule (e.g. OEM variants) and we invite you to refer to our technical staff for assistance.

FEG 506 20 61 AA LMRK6-16E1ZL6-16E9ZSK6 16 EZ716 MA1
FEG 639 20 61 AA LMRK6-22E1ZL6-22E9ZSK6 22 EZ721 MA1
FEG 740 20 61 AA LMRK6-25E1ZL6-25E9ZSK6 25 EZ725 MA1
FEG 836 20 61 AA LMRK6-29E1ZL6-29E9ZSK6 29 EZ729 MA1
FEG 945 20 61 AA LMRK6-33E1ZL6-33E9ZSK6 33 EZ733 MA1
FEG 1047 20 61 AA LMRK6-37E1ZL6-37E9ZSK6 37 EZ737 MA1
FEG 1190 20 61 AA LMRK6-43E1ZL6-43E9ZSK6 43 EZ742 MA1

Custom designs

  • Double drilled or custom drilling patterns
  • Higher precision bearings with location diameters
  • Reduced internal clearance (Class 5 & Class 6)
  • Black oxide (standad) or zinc plating (to order) for enhanced corrosion protection
  • Epoxy paint or even Nylon coated units to special order
  • Stainless steel or aluminium versions


FUN20 Imperial Series slewing rings are normally produced in 50Mn / C45.

Internal construction

Standard FEG20 Imperial Series bearings incorporate plastic spacers, but ball spacers, steel or brass spacers, or even full complement and caged designs can be supplied for specific applications.


A land riding NBR (nitrile rubber) seal strip is standard. VITON seals can be supplied to order.


The FEG20 Imperial series has a standard 20° pressure angle, uncorrected spur gear cut into the outer ring.


QCB® Slewing rings are assembled with a small quantity of Lithium EP2 grease. It is important that all slewing rings are greased during installation and prior to operation. FEG20 Imperial series slewing rings will usually have 4 or 6 grease nipples DIN 71412 M8x1 on the radial face of each ring. Sufficient grease nipples for all holes as well as Nylon plugs (to insert if a grease nipple is not required) are supplied with each ring.

Special greases can be supplied on demand as can GreaseMax Automatic Lubricators and Accessories.

Load & Bolt limit curves

If both a radial and an axial load act on the bearing these must be combines into a single equivalent load to enable basic selection from the load curves. The raceway limit is illustrated by the blue line, the red line illustrates the limit for the specified number of Grade 10.9 bolts. The load point should be well under the relevant load curve for long life.

Grade 8.8 bolts can be used but only after approval by our technical team.

Similarly if the load is suspended or the axis of rotation is not vertical please refer the application details to us and take advantage of our decades of experience!

QCB referencePDF printCAD.dwgMODEL.STP
FEG 506 20 61 AA LMFEG 506 20 61.pdfFEG 506 20 61.dwgFEG 506 20 61.STP
FEG 639 20 61 AA LMFEG 639 20 61.pdfFEG 639 20 61.dwgFEG 639 20 61.STP
FEG 740 20 61 AA LMFEG 740 20 61.pdfFEG 740 20 61.dwgFEG 740 20 61.STP
FEG 836 20 61 AA LMFEG 836 20 61.pdfFEG 836 20 61.dwgFEG 836 20 61.STP
FEG 945 20 61 AA LMFEG 948 20 61.pdfFEG 945 20 61.dwgFEG 945 20 61.STP
FEG 1047 20 61 AA LMFEG 1047 20 61.pdfFEG 1047 20 61.dwgFEG 1047 20 61.STP
FEG 1190 20 61 AA LMFEG 1190 20 61.pdfFEG 1190 20 61.dwgFEG 1190 20 61.STP

Associated Products

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