Bull Head Live Center (BP80 / BP60 / BP60A) Overview
A comprehensive document covering the working principle, key features, full dimension tables (BP80, BP60, BP60A) and selection guidance for the bull head live center family used on pipe, tube and large center-hole workpieces.
Overview
▲ Product appearance (POINTTECH catalog)
A bull head live center is a rotating tailstock tool mounted in the tailstock of a lathe or CNC lathe that turns together with the workpiece. Unlike a dead (fixed) center, its internal bearings spin at the same speed as the part, eliminating friction, heat build-up and galling at the center hole and allowing stable support even at high spindle speeds. The defining feature of the bull head family is its unusually large 'bull head' cone: this oversized cone seats with face contact against the chamfered edge of workpieces that are hollow or have very large center holes — such as pipe and tube — and supports them firmly.
POINTTECH offers three variants distinguished by cone angle and geometry. BP80 uses an 80° wide-angle cone suited to heavy-duty, heavy-cut pipe machining, while BP60 (standard) and BP60A (extended) use a 60° cone and serve both as a centering taper for hollow bodies and as a general-purpose live center for standard workpieces. The BP60A has a longer extended point for better access to deep center holes or stepped parts. All models connect directly to the tailstock through a Morse taper (MT) shank.
Key Features
- Accuracy: guaranteed 0.003mm TIR run-out (0.0001"), keeping roundness and surface finish consistent during machining.
- Large cone design: dedicated to pipe and tube work and to parts with extra-large center holes; broad face contact supports thin-wall and hollow workpieces without distortion.
- Heat-treated point: cone and spindle hardened to HRc 60±2 for wear resistance and long service life.
- Run-out adjustment (BP80): the shaking of the head part can be fine-tuned with a screw to recover accuracy over long service.
- Sealed design (BP80): prevents ingress of coolant and chips into the bearings, extending life.
- Heavy-duty capability (BP80): optimized for heavy-cut lathe operations and high axial loads.
- Dual purpose (BP60/BP60A): usable both as a centering taper for hollow bodies and as a center for machining standard workpieces.
Caution: the maximum R.P.M and workpiece weight in the tables are interdependent. As speed rises, the permissible workpiece weight and axial load fall (see the technical-data curves), so verify the allowable load at your actual operating speed. The heat-treated hardness (HRc 60±2) and the 0.003mm run-out are only assured with a correctly machined, clean center hole and proper thrust loading.
Specifications
BP80 (80° Bull Head)
MODEL | MT | A | B | C | L | Workpiece Weight | Max R.P.M | Max Run Out |
|---|---|---|---|---|---|---|---|---|
083003 | 3 | 95 | 20 | 85 | 145 | 400 | 4,000 | 0.003 |
083004 | 4 | 125 | 29 | 108 | 185 | 800 | 3,000 | 0.003 |
083005 | 5 | 150 | 32 | 136 | 226 | 1,600 | 2,000 | 0.003 |
083006 | 6 | 200 | 38 | 189 | 309 | 2,500 | 1,500 | 0.005 |
BP60 (60° Standard Type)
MODEL | MT | A | B | C | L | Workpiece Weight | Max R.P.M | Max Run Out |
|---|---|---|---|---|---|---|---|---|
081002 | 2 | 44 | 66 | 68 | 134 | 400 | 5,000 | 0.003 |
081003 | 3 | 56 | 76.5 | 85 | 161.5 | 400 | 5,000 | 0.003 |
081004 | 4 | 78 | 100 | 108 | 208 | 800 | 3,800 | 0.003 |
081005 | 5 | 98 | 125 | 136 | 261 | 1,600 | 3,000 | 0.003 |
081006 | 6 | 118 | 154 | 189 | 343 | 2,500 | 2,500 | 0.005 |
BP60A (60° Extended A Type)
MODEL | MT | A | B | C | L | Workpiece Weight | Max R.P.M | Max Run Out |
|---|---|---|---|---|---|---|---|---|
085002 | 2 | 44 | 79 | 68 | 147 | 320 | 5,000 | 0.003 |
085003 | 3 | 56 | 86 | 85 | 171 | 320 | 5,000 | 0.003 |
085004 | 4 | 78 | 103.5 | 108 | 211.5 | 560 | 3,800 | 0.003 |
085005 | 5 | 98 | 140 | 136 | 276 | 1,200 | 3,000 | 0.003 |
085006 | 6 | 118 | 165 | 189 | 354 | 2,000 | 2,500 | 0.005 |
Units are mm and kg; MT is the Morse taper number. These tables reproduce the most frequently used columns (A, B, C, L and performance values) from the catalog dimension tables; refer to the original drawings for the full geometry (B, C, D, E, F, G, K, etc.).
Selection Guide
Start by matching the Morse taper of your tailstock sleeve (MT2–MT6) to the correct model row. Then choose the cone angle: for heavy roughing of thin-wall pipe and tube, the wide 80° BP80 offers a larger face-contact area that resists distortion and chatter. For centering hollow parts or for combined standard-workpiece machining, the 60° BP60 is the standard choice; where deep center holes or step clearance are needed, choose the BP60A with its longer extended point.
On the performance side, read target speed and workpiece weight together. Small MT2/MT3 models reach up to 5,000 rpm but carry less weight, whereas large MT6 models support up to 2,500 kg at a lower top speed of 1,500–2,500 rpm. Using the workpiece-weight-vs-rpm and axial-load-vs-rpm curves in the catalog, choose one size up where possible so that ample load margin remains at your actual operating speed.
Applications
- Outer-diameter and face machining of hollow workpieces such as pipe, tube and hollow shafts
- Lathe support of large parts with very large center holes
- Heavy-duty, heavy-cut lathe operations (especially BP80)
- Centering taper for hollow bodies combined with standard-workpiece machining (BP60/BP60A)
- Manufacture of tubular components such as hydraulic cylinder tubes, rollers and pipe fittings