UCPA200 Series Tapped Base Pillow Block Bearing Units — Threaded Base Holes, Setscrew Locking
Standard pillow block housings use clearance holes in the base through which bolts pass from below, allowing positional adjustment before tightening. The UCPA200 series reverses this arrangement: the housing base contains tapped (threaded) holes, and the mounting bolts thread directly into the housing from below the machine frame. This allows the bearing unit to be positioned precisely on a frame that has clearance slots or a pre-drilled grid pattern, and it eliminates the need for a nut on the top of the housing base — which matters in installations where above-base access is restricted.
Tapped Base Configuration — Precision Positioning Advantages
The tapped base design is particularly valuable in three installation scenarios. First, when the bearing must be set to an exact position along a slotted mounting rail and locked there permanently. Second, when the above-housing space is occupied by a guard, cover plate, or adjacent component that prevents access for a conventional nut. Third, when both metric and inch bolt standards must be accommodated in the same installation — the UCPA200 is available with both metric (G column) and equivalent inch UNC thread sizes.
Key Features
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Tapped (Threaded) Base Holes
Bolts thread directly into housing from below. No nut required above base. Enables access from one side only and prevents positional shift after torquing.
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Metric and Inch Thread Options
G column specifies tapped thread size. Available in metric (M10, M14, M16) and equivalent UNC inch threads.
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Setscrew Locking Insert
Standard dual setscrew retention as per UCP200 — same shaft tolerance requirements and maintenance procedure.
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Self-Aligning Insert Bearing
Spherical OD on UC insert accommodates 2° misalignment. Tapped base positions precisely; self-aligning insert compensates residual angular error.
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Compact Base Profile
Tapped base housing has a shorter base section (J dimension) than equivalent UCP200 in some bore ranges.
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Drop-In for UCPA-Pattern Designs
GB, ISO, ANSI, JIS dimensional compliance. Replaces existing UCPA-style tapped base units from any manufacturer.
Full Dimensional Specifications
| Unit No. | d mm | d inch | H mm | L mm | J mm | A mm | G | H1 mm | H0 mm | B mm | S mm | Bolt | kg |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UCPA201~203 / 201-8~203-11 | 12~17 | 1/2~11/16 | 30.2 | 76 | 52 | 38 | M10 | 11 | 62 | 31 | 12.7 | M10 | 0.67 |
| UCPA204 / 204-12 | 20 | 3/4 | 30.2 | 76 | 52 | 38 | M10 | 11 | 62 | 31 | 12.7 | M10 | 0.60 |
| UCPA205 / 205-14/15/16 | 25 | 7/8~1 | 36.5 | 84 | 56 | 38 | M10 | 12 | 72 | 34.1 | 14.3 | M10 | 0.81 |
| UCPA206 / 206-17~20 | 30 | 1-1/16~1-1/4 | 42.9 | 94 | 66 | 48 | M14 | 12 | 84 | 38.1 | 15.9 | M14 | 1.20 |
| UCPA207 / 207-20~23 | 35 | 1-1/4~1-7/16 | 47.6 | 110 | 80 | 48 | M14 | 13 | 95 | 42.9 | 17.5 | M14 | 1.70 |
| UCPA208 / 208-24/25 | 40 | 1-1/2~1-9/16 | 49.2 | 116 | 84 | 54 | M14 | 13 | 100 | 49.2 | 19.0 | M14 | 1.90 |
| UCPA209 / 209-26~28 | 45 | 1-5/8~1-3/4 | 54.2 | 120 | 90 | 54 | M14 | 13 | 108 | 49.2 | 19.0 | M14 | 2.20 |
| UCPA210 / 210-30~32 | 50 | 1-7/8~2 | 57.2 | 130 | 94 | 60 | M16 | 14 | 116 | 51.6 | 19.0 | M16 | 2.60 |
| UCPA211 / 211-32~35 | 55 | 2~2-3/16 | 63.5 | 140 | 104 | 66 | M16 | 14 | 125 | 55.6 | 22.2 | M16 | 3.00 |
| UCPA212 / 212-36~39 | 60 | 2-1/4~2-7/16 | 69.9 | 150 | 114 | 68 | M16 | 17 | 138 | 65.1 | 25.4 | M16 | 4.24 |
→ Scroll table horizontally to view all columns. Catalogue dimensions for reference only — engineering drawings required before order.
G = tapped thread in housing base (mounting bolt engages this thread). Minimum bolt engagement depth: 1.5 × bolt diameter. Confirm metric or inch thread standard at order.
Applications
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CNC & Precision Machine Tool Supports
Ballscrew support bearings and precision spindle shaft supports in CNC routers, laser cutters, and engraving machines where exact shaft positioning determines machining accuracy.
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Slotted Rail Mounting Systems
Bearing units mounted on T-slot aluminium extrusion or steel slotted rail systems where the tapped base can engage the slot nut from below, allowing precise shaft positioning along the rail length.
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Enclosed Machine Frame Installations
Any installation where a fixed cover, safety guard, or secondary machine frame member sits immediately above the bearing mounting base, preventing access for conventional nut-and-bolt assembly from above.
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Agricultural Equipment OEM Builds
Implement frame bearings on seed drills, cultivator drive frames, and sprayer booms where the tapped base allows mounting from the accessible side of thin-walled frame sections.
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Packaging Machine Frame Builds
Bearing positions in packaging machine frames where the bearing is mounted after the frame top cover is fitted, requiring bolting from below only.
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Retrofit in Restricted-Access Positions
Replacement bearings in machines where the original design used tapped base units and the above-housing area has since been enclosed by added guarding.
📦 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.
UCPA200 vs UCP200 — When Tapped Base is the Right Choice
Use UCPA200 when: (1) only one-side bolt access is available; (2) exact shaft positioning without positional drift after torquing is required; (3) bolt-on nut hardware above the base creates a clearance problem. Use UCP200 when positional adjustment before final lock-down is needed, or when the mounting structure allows through-bolt assembly. For the same tapped base housing but with a concentric locking collar insert, the UEPA200 series provides this combination.
Frequently Asked Questions
What thread is in the tapped base?
G column gives the thread: M10 for UCPA205, M14 for UCPA206–207, M16 for UCPA210–212. Inch UNC available on request.
How long should the mounting bolt be?
Minimum 1.5 × bolt diameter engagement into housing. For M10: minimum 15 mm engagement depth.
Is it interchangeable with UCP200?
Insert bearing is interchangeable. Housing footprint (J, A) may differ — verify against UCPA200 drawing 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 UCPA200 Series
Specify shaft diameter, thread standard (metric or UNC inch), bore type, and mounting bolt length requirement. Contact us.
