UCSB200 Series Pillow Block Bearing Units — Wide-Slot Compact Housing, Anti-Vibration Design
The UCSB200 series takes a different approach to the standard pillow block geometry: a wider, lower housing body with an extended bolt slot (A1 dimension) that increases the effective moment arm of the mounting bolts relative to the bearing centreline. This wider base stance reduces the angular deflection of the housing under eccentric radial load — the condition that occurs whenever belt tension, chain pull, or impeller weight acts at a point not directly between the two mounting bolts.
Wide-Slot Housing Geometry — Stability Under Eccentric Load
The most significant dimensional difference between UCSB200 and UCP200 is the A1 measurement — the distance from the housing centreline to the inner edge of the mounting slot. At UCSB207 (35 mm bore), A1 = 33 mm. This extended slot engagement means the UCSB200 mounting bolt is under tension further from the housing centreline, creating a larger resisting moment against housing rotation under side load. In practical terms, this means the UCSB207 housing tilts less than a UCP207 under the same belt tension, preserving bearing alignment and reducing the cyclic load on the bearing outer ring seat.
Key Features
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Wide-Base Extended Bolt Slot
A1 slot extension increases the moment arm of mounting bolts against housing rotation under eccentric load. Better alignment maintenance under belt tension than narrow-base UCP200.
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Setscrew Locking at 120°
Standard dual setscrew retention — same maintenance procedure as UCP200. Compatible with metric and inch bore inserts.
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Wide Inner Ring Self-Aligning Insert
UC series wide inner ring insert bearing. Spherical OD compensates up to 2° angular misalignment.
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Compact Height Profile
H dimension is lower than UCP200 for equivalent bore sizes. Suitable where mounting height is constrained.
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Metric and Inch Bolt Hole
Both mm and inch bolt hole specifications listed. Fits machine frames drilled to either standard.
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Accessible Grease Point
Grease fitting standard. Wide housing profile and lower centre height make the grease nipple easily accessible.
Full Dimensional Specifications
| Unit No. | d mm | d inch | H mm | L mm | J mm | A mm | A1 mm | H1 mm | H0 mm | N mm | B mm | S mm | Bolt mm | Bolt in | kg |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UCSB205 / 205-13~16 | 25 | 13/16~1 | 31.7 | 92 | 70 | 38 | 25 | 58 | 67 | 12 | 34.1 | 14.3 | M10 | 3/8 | 1.03 |
| UCSB206 / 206-17~20 | 30 | 1-1/16~1-1/4 | 38.1 | 108 | 83 | 44 | 30 | 68 | 78 | 12 | 38.1 | 15.9 | M10 | 3/8 | 1.63 |
| UCSB207 / 207-20~23 | 35 | 1-1/4~1-7/16 | 44.4 | 133 | 102 | 48 | 33 | 76 | 95 | 14 | 42.9 | 17.5 | M12 | 7/16 | 2.52 |
| UCSB208 / 208-24/25 | 40 | 1-1/2~1-9/16 | 47.6 | 140 | 108 | 54 | 39 | 81 | 100 | 14 | 49.2 | 19 | M12 | 7/16 | 3.12 |
| UCSB209 / 209-26~28 | 45 | 1-5/8~1-3/4 | 50.8 | 146 | 111 | 54 | 39 | 86 | 105 | 14 | 49.2 | 19 | M12 | 7/16 | 3.43 |
| UCSB210 / 210-29~32 | 50 | 1-13/16~2 | 53.97 | 152 | 118 | 60 | 41 | 90 | 110 | 14 | 51.6 | 19 | M12 | 7/16 | 3.95 |
| UCSB211 / 211-32~35 | 55 | 2~2-3/16 | 58.7 | 172 | 137 | 60 | 41 | 98 | 122 | 17 | 55.6 | 22.2 | M16 | 5/8 | 4.92 |
| UCSB212 / 212-36~39 | 60 | 2-1/4~2-7/16 | 69.85 | 197 | 162 | 65 | 48 | 111 | 146 | 17 | 65.1 | 25.4 | M16 | 5/8 | 7.03 |
| UCSB213 / 213-40/41 | 65 | 2-1/2~2-9/16 | 69.85 | 197 | 162 | 65 | 48 | 111 | 146 | 17 | 65.1 | 25.4 | M16 | 5/8 | 7.62 |
| UCSB214 / 214-42~44 | 70 | 2-5/8~2-3/4 | 76.2 | 206 | 172 | 73 | 60 | 117 | 155 | 17 | 74.6 | 30.2 | M16 | 5/8 | 8.18 |
| UCSB215 / 215-45~48 | 75 | 2-13/16~3 | 76.2 | 206 | 172 | 73 | 55 | 117 | 155 | 17 | 77.8 | 33.3 | M16 | 5/8 | 8.42 |
| UCSB216 / 216-50 | 80 | 3-1/8 | 82.55 | 238 | 191 | 86 | 64 | 127 | 168 | 21 | 82.6 | 33.3 | M20 | 3/4 | 10.55 |
| UCSB217 / 217-52 | 85 | 3-1/4 | 88.9 | 254 | 203 | 89 | 64 | 136 | 181 | 21 | 85.7 | 34.1 | M20 | 3/4 | 13.00 |
| UCSB218 / 218-56 | 90 | 3-1/2 | 98.4 | 273 | 222 | 92 | 67 | 152 | 200 | 25 | 96 | 39.7 | M24 | — | 16.29 |
| UCSBX20 / 20-63/64 | 100 | 3-15/16~4 | 108 | 298 | 241 | 108 | 70 | 178 | 221 | 26 | 108 | 49.2 | M24 | — | 23.52 |
→ Scroll table horizontally to view all columns. Catalogue dimensions for reference only — engineering drawings required before order.
A1 = extended slot inner edge dimension. Both metric and inch bolt hole sizes listed. Catalogue dimensions for reference only.
Applications
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Belt Drive Head & Tail Pulleys
Conveyor belt drive and tail pulley shafts where belt tension creates a side load on the housing. UCSB wider bolt stance reduces housing tilt under this load.
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Fan & Blower Belt Drives
V-belt driven fan shafts where belt pre-tension and unbalanced aerodynamic loads combine to create persistent eccentric radial forces on the bearing housing.
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Agricultural Harvester Drives
Combine threshing cylinder and fan belt drive shafts where crop load variability creates peak eccentric bearing loads.
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Packaging Machine Main Drives
Primary drive shaft bearings in wrapping and sealing machines where timing belt tension must be maintained precisely.
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Quarry & Aggregate Vibrating Screens
Screen deck eccentric shaft supports where high vibration amplitudes demand housing stability beyond what standard UCP200 provides.
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General Belt-Drive Upgrade
Drop-in upgrade from UCP200 on any belt-drive installation where bearing life is shorter than calculated.
📦 MOQ & Order Information
- Standard parts: quantity-based MOQ applies per model number.
- High-value / large items: minimum order by USD order value.
- New-client samples: 1–5 pcs available at sample price for first-time buyers.
- Multi-model combines: aggregate orders of USD 1,500 or more across models accepted.
- Special materials / processes: subject to process MOQ — confirm at inquiry stage.
- Retail (1–2 pcs): not accepted. Minimum sample order is 1–5 pcs at sample pricing.
Detailed engineering drawings must be submitted and approved before order confirmation. Catalogue dimensions are for reference only.
UCSB200 vs UCP200 — When to Upgrade
The UCSB200 is appropriate when bearing replacement frequency is higher than bearing life calculations predict, often indicating that housing alignment shift under belt load is reducing effective bearing capacity. If a UCP200 installation on a belt drive shows outer ring fretting in the housing bore, the housing is rotating under load and UCSB200 wider base stance will address this. For heavier loads where housing stiffness alone is insufficient, consider the UCPX00 medium duty series which adds heavier housing section.
Frequently Asked Questions
How does UCSB200 differ from UCP200?
Wider A1 slot extension and lower H dimension. J bolt circle is identical — direct retrofit without re-drilling.
Is the bolt pattern compatible with UCP200?
Yes. J dimension matches UCP200 for equivalent bore. No frame modification needed.
Does lower H cause clearance issues?
Yes — verify pulley, coupling, and guard clearances at the lower shaft centreline height before retrofitting.
What is the MOQ?
Standard parts: quantity-based MOQ. Samples 1–5 pcs. Multi-model from USD 1,500. Retail 1–2 pcs not accepted.
Request a Quote for UCSB200 Series
Provide shaft diameter, bore type, belt drive details, and current bearing replacement frequency. Contact us.
