SCHUNK is known globally for grippers, but the company's range spans three clamping disciplines: gripping systems (the robot's hand), tool clamping (holding the cutting tool on the spindle) and workpiece clamping (holding the part on the machine table). This guide covers the two clamping technologies that complete the picture after the gripper.
1. SCHUNK's Three Clamping Disciplines
| Discipline | Where it works | What it holds |
|---|---|---|
| Gripping systems | Robot end-effector | Workpieces being picked and placed |
| Tool clamping | Machine spindle | Cutting tools (drills, mills, reamers) |
| Workpiece clamping | Machine table / fixture | Workpieces during machining |
2. Tool Clamping — Precision on the Spindle
Tool clamping determines machining precision, surface quality and tool life. SCHUNK's tool-holder families cover the main clamping principles:
- Hydraulic expansion chucks (TENDO / CELSIO) — the TENDO SVL and CELSIO SVL use hydraulic pressure to clamp the tool with maximum concentricity (run-out accuracy to a few microns). Ideal for finishing and high-speed machining where precision pays.
- Shrink-fit chucks (TRIBOS) — thermal clamping for the highest rigidity at high speeds.
- Mechanical clamping (HSK adapters, collets) — versatile and economical for general machining.
If run-out accuracy, vibration damping or tool life is the bottleneck in your machining, hydraulic expansion chucks are the fastest win.
3. Workpiece Clamping — Stability on the Table
Workpiece clamping holds the part securely during machining. SCHUNK's families include:
- Chucks and mandrels — for cylindrical parts, offering repeatable centring.
- Clamping stations and fixtures — such as the SBS series, for flexible palletised clamping and quick changeover.
- Clamping systems for machine tools — manual, pneumatic and hydraulic variants depending on the production volume.
The goal is the same as gripping: hold the part with defined force, no deformation, and repeatable positioning — so the machining result is consistent from part to part.
4. How the Three Disciplines Work Together
A typical automated machining cell uses all three: the gripper (see our gripper selection guide) loads the blank onto the fixture, the workpiece clamping system holds it during machining, and the tool clamping system holds the cutting tool on the spindle. Matching all three from one supplier simplifies engineering, documentation and spares.
Buying Guide for Glorient Customers
Glorient supplies genuine SCHUNK tool and workpiece clamping components with competitive pricing and worldwide delivery. To select the right system:
- Confirm the discipline: spindle tool holding or table-side workpiece holding.
- Note your spindle taper (HSK, BT, SK), tool diameter or workpiece size.
- Browse the tool clamping range or workpiece clamping range, or send your details via the quote request form — our engineers will confirm the correct holder within 24 hours.
SCHUNK's three clamping disciplines cover the full machine tool cycle: grip it, hold it, machine it. Choose each one correctly and the cell runs with precision — and with genuine SCHUNK from Glorient, the spares stay available.
Frequently Asked Questions
What is the difference between manual and hydraulic workpiece clamping?
Manual clamping is operated by hand and suits low-volume or flexible setups. Hydraulic clamping applies high, repeatable force via a pump and is preferred for high-volume machining where clamping force must be consistent and automated.
How do I choose a tool holder - HSK or SK?
HSK is the hollow-shank interface for high-speed machining with better accuracy and stiffness at high RPM. SK (steep taper) is the traditional, lower-cost standard. Choose HSK for high-speed and high-precision machining; SK for general-purpose machining.
What clamping force do I need for machining?
The clamping force must exceed the cutting forces by a safe margin to prevent the workpiece shifting during machining. It depends on the material, cut depth, feed and tool geometry - calculate from the maximum cutting force plus a safety factor.