Take-up bearing units: UCT sizes, frames and conveyor adjustment
A take-up bearing unit supports a shaft in a housing that can move along a compatible frame or guide. The adjuster changes the shaft position for the machine’s tension or tracking arrangement; the insert’s set screws separately lock the bearing to the shaft. Select the unit, frame, adjuster and travel together. A UCT housing length is not its available take-up travel.
On this page14 sections ⌄
Take-up unit, take-up housing and take-up frame are not the same part
“Take up”, “take-up”, “takeup bearing” and “UCT bearing” often refer to this adjustable support. They do not prove that a loose UCT unit includes its frame or tensioning screw. A fixed UCP pillow block is not converted into a verified take-up assembly merely by elongating mounting holes.
On smaller screens, scroll the table sideways to read all columns.
| Component | Function | What a search result must identify |
|---|---|---|
| Insert bearing | Supports the rotating shaft and locks to it by its designated system | Bore, load/speed suitability, seals and locking details |
| Take-up housing | Holds the insert and interfaces with the moving guide | Envelope, guide-seat shape and adjustment connection |
| Frame / guide | Constrains the housing’s adjustment path | Guide dimensions, structural rating, usable stroke and retention |
| Adjusting screw / tensioning arrangement | Moves or loads the take-up assembly | Thread/connection, permissible load, travel and locking provision |
| Complete machine arrangement | Maintains shaft alignment and belt/chain operation | Required tension, tracking procedure and safe access |
NTN UCT201–UCT217 metric take-up unit dimensions
Selected nominal dimensions from NTN 2400/E, printed pages 212, 214 and 216. All numeric dimensions in this table are mm. H, L, A, H1 and B retain the drawing symbols; they are not a fabrication drawing for a frame.
H and L describe the housing envelope; B describes inner-ring width. H1 is a guide-related height in this take-up drawing, not the shaft-centre height used in a pillow-block drawing. Do not transfer symbol meanings between different housing types.
The D1 entries are the relubricatable versions in this reference. The table does not state frame travel or certify a permissible belt tension. Those require the chosen frame, adjuster, bearing performance and machine load calculation.
On smaller screens, scroll the table sideways to read all columns.
| Complete unit | Shaft bore | Housing H | Housing L | A | H1 | Inner-ring B |
|---|---|---|---|---|---|---|
| UCT201D1 | 12 | 89 | 94 | 32 | 76 | 31 |
| UCT202D1 | 15 | 89 | 94 | 32 | 76 | 31 |
| UCT203D1 | 17 | 89 | 94 | 32 | 76 | 31 |
| UCT204D1 | 20 | 89 | 94 | 32 | 76 | 31 |
| UCT205D1 | 25 | 89 | 97 | 32 | 76 | 34.1 |
| UCT206D1 | 30 | 102 | 113 | 37 | 89 | 38.1 |
| UCT207D1 | 35 | 102 | 129 | 37 | 89 | 42.9 |
| UCT208D1 | 40 | 114 | 144 | 49 | 102 | 49.2 |
| UCT209D1 | 45 | 117 | 145 | 49 | 102 | 49.2 |
| UCT210D1 | 50 | 117 | 151 | 49 | 102 | 51.6 |
| UCT211D1 | 55 | 146 | 171 | 64 | 130 | 55.6 |
| UCT212D1 | 60 | 146 | 194 | 64 | 130 | 65.1 |
| UCT213D1 | 65 | 167 | 224 | 70 | 151 | 65.1 |
| UCT214D1 | 70 | 167 | 224 | 70 | 151 | 74.6 |
| UCT215D1 | 75 | 167 | 232 | 70 | 151 | 77.8 |
| UCT216D1 | 80 | 184 | 235 | 70 | 165 | 82.6 |
| UCT217D1 | 85 | 198 | 260 | 73 | 173 | 85.7 |
Inch shaft versions: do not round to the nearest metric bore
Examples from the same NTN UCT2 catalogue. The explicit shaft values, not a guessed universal suffix decoder, establish the bore.
UCT205D1 has a 25 mm shaft bore in the metric table; UCT205-100D1 is the 1-inch / 25.4 mm version. They are not the same bore. The conversion column is exact arithmetic from the listed inch shaft size, not a new measured tolerance.
UCT206-104D1 and UCT207-104D1 demonstrate that the same 1 1/4-inch bore can occur in different unit sizes. Match the complete frame interface and load requirements, not only the number on the shaft.
On smaller screens, scroll the table sideways to read all columns.
| Unit designation | Shaft diameter in | Exact conversion mm |
|---|---|---|
| UCT201-008D1 | 1/2 | 12.7 |
| UCT204-012D1 | 3/4 | 19.05 |
| UCT205-014D1 | 7/8 | 22.225 |
| UCT205-100D1 | 1 | 25.4 |
| UCT206-104D1 | 1 1/4 | 31.75 |
| UCT207-104D1 | 1 1/4 | 31.75 |
| UCT208-108D1 | 1 1/2 | 38.1 |
| UCT210-200D1 | 2 | 50.8 |
UCT2 guide and adjuster dimensions: separate from housing size
NTN 2400/E table 10.4, printed page 50. All values below are mm; symbols retain the source assembly drawing meaning. The tolerance belongs to e′ only. d here identifies the adjusting-bolt dimension, not the bearing bore.
These values describe the guide and adjusting-bolt/nut interface illustrated in that catalogue. They do not supply a complete frame drawing, thread pitch, frame material, strength rating or useful stroke. Retain the specified pin/retention arrangement and full assembly dimensions.
For UCT205, the housing table gives H1 = 76 mm while this guide reference gives e′ = 76.5 mm with its own tolerance. They are different mating dimensions, not competing measurements to overwrite in a product record. Neither value is the frame travel.
On smaller screens, scroll the table sideways to read all columns.
| Unit group | Guide e′ | e′ tolerance | Guide k′ | Adjuster d | D | b |
|---|---|---|---|---|---|---|
| UCT201–205 | 76.5 | +0.5 / 0 | 11 | 16 | 28 | 12 |
| UCT206–207 | 89.5 | +0.5 / 0 | 11 | 18 | 32 | 12 |
| UCT208–210 | 102.5 | +0.5 / 0 | 15 | 25 | 42 | 14 |
| UCT211 | 130.5 | +0.8 / 0 | 20 | 30 | 55 | 20 |
| UCT212 | 130.5 | +0.8 / 0 | 20 | 30 | 55 | 26 |
| UCT213–215 | 151.5 | +0.8 / 0 | 24 | 36 | 60 | 26 |
| UCT216 | 165.5 | +0.8 / 0 | 24 | 36 | 60 | 26 |
| UCT217 | 173.5 | +1.0 / 0 | 28 | 42 | 60 | 30 |
What to measure on a take-up frame
NTN table 10.4 provides series-specific guide and adjuster dimensions separately from the UCT bearing-unit table. Use the correct assembly drawing for the frame. This page deliberately does not invent a frame part number or travel from housing envelope dimensions.
Take-up adjustment, shaft locking and axial location are three different functions. Moving a housing does not lock its insert onto the shaft, and locking the insert does not secure the frame’s adjustment. Retain each specified locking and retention provision.
On smaller screens, scroll the table sideways to read all columns.
| Check | Record | Do not infer |
|---|---|---|
| Guide spacing and fit | Specified mating guide dimensions, tolerances and sliding clearance | That another frame accepts the unit because both have a 25 mm shaft |
| Guide cross-section | Groove/contact surfaces, support length and retention details | That housing H1 alone defines the complete guide |
| Adjustment connection | Opening, nut or screw interface and retention arrangement | That an opening diameter specifies a thread pitch |
| Available stroke | Usable movement between approved limits with adequate guide engagement | That housing length L is take-up travel |
| Adjustment load | Permitted load of screw, nut, frame, housing and attachment | That insert dynamic rating C is permissible screw force |
| Alignment | Both shaft-end positions, squareness and pulley/sprocket plane | That equal exposed screw lengths guarantee tracking |
Belt tension, tracking and load capacity
Determine the required tension and shaft reactions using the equipment geometry and operating loads. The forces from two belt spans act as vectors at the pulley; the bearing reactions also depend on support spacing and overhung loads. Do not equate a single tension number directly with every bearing load.
Check the insert bearing, housing, guides, adjuster, fasteners and machine structure separately under the required duty. A bearing dynamic load rating is an input to fatigue-life evaluation under defined conditions; it is not automatically the safe working load of the take-up frame.
Excessive tension can raise bearing load, shaft deflection and heat. Unequal adjustment can skew the shaft and upset tracking. Follow the conveyor or machine’s prescribed tension and alignment method rather than repeatedly tightening one side to chase a symptom.
Do not reach into an operating belt or chain drive to adjust an ordinary take-up. Isolate the machine and control stored mechanical energy before work unless a specific engineered system and documented procedure explicitly provide safe live adjustment.
Take-up bearing questions
Does UCT include the take-up frame?
The cited UCT table identifies the bearing unit, not a complete frame with a specified travel. Confirm the actual supply and assembly drawing rather than assuming the frame and adjusting screw are included.
Can I use a pillow block instead?
A fixed pillow block and a guided take-up unit have different mounting functions. A replacement requires a documented machine arrangement; matching the shaft bore is insufficient.
How much travel does a UCT205 have?
The UCT205D1 housing table gives envelope and interface dimensions, not frame stroke. Travel is determined by the compatible frame, adjuster and permitted guide engagement.
Is the D1 unit permanently sealed?
In this NTN UCT2 reference D1 denotes the listed relubricatable version. Grease type and interval still depend on the actual application and instructions; the suffix is not a universal code across brands.
What the evidence can — and cannot — tell you
| Observation or context | Interpretation to consider | Verification needed |
|---|---|---|
| Shaft support | Actual bore, insert and locking method | Match metric and inch versions exactly. |
| Moving housing | Housing envelope, guide surfaces and adjustment connection | Same shaft bore does not establish frame compatibility. |
| Frame and adjuster | Usable stroke, guide geometry, adjuster and retention | Do not read catalogue housing length as travel. |
| Machine duty | Belt or chain force, shaft reactions and alignment | Bearing capacity alone does not rate the entire tensioning assembly. |
A practical investigation sequence
Identify and record
Identify the conveyor or machine arrangement, complete bearing unit, shaft diameter and the installed take-up frame. Record the intended adjustment direction, current position, required travel and how both shaft ends remain aligned.
Check the context
Compare the actual unit drawing with the frame guides, adjustment connection and space envelope. Use the exact metric or inch designation; include the insert, seals and relubrication version.
Verify before acting
Check shaft reactions and the permitted loads of the bearing, housing, frame, adjuster, fasteners and surrounding structure. Determine required belt or chain tension from the equipment specification, not by tightening until slack disappears.
Keep the decision traceable
With the equipment safely isolated and stored loads controlled, fit and align the specified components. Set tension and tracking by the equipment procedure, secure its adjustment locks and retainers, and verify guarded operation and recheck requirements.
Capture the information a model search cannot guess
Keep this checklist with your inspection or comparison. Checking a box only records that you have collected the item; it does not certify the bearing.
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Technical basis & editorial scope
Original BearingScope workflow, written for catalogue research and comparison. Manufacturer material is used to check principles, not copied as a product endorsement or substituted for model-specific instructions. Reviewed 1 October 2026.
- NTN Bearing Units catalogue 2400/E, technical data, printed pages 50–60 — Guide/frame dimensions, housing mounting, insert locking and replacement; series-specific reference, not a universal torque standard.
- NTN Bearing Units catalogue 2400/E, UCT2, printed pages 212–216 — Metric and inch take-up unit designations and nominal dimensions; D1 lubrication scope retained.
Source addresses and collection status are retained in the internal audit. No unpublished dimensions, torque settings, service intervals or interchange approvals are inferred.