Airtac BSAI Locking Clamp Cylinder BSAI40X25
The AirTAC Airtac BSAI Locking Clamp Cylinder BSAI40X25 is a genuine double-acting ISO 15552 cylinder with a Ø40mm bore, 25mm stroke and a spring-applied, air-released clamp-lock that holds the rod at ANY position along its travel — with a static holding force of 900 N.
- BoreØ40 mm
- Stroke25 mm
- Cylinder portG1/4
- TypeSingle rod (BSAI)
- Enclasp portG1/8
- Rod threadM12×1.25
- No minimum order. A single piece can be ordered.
- Ready in 3–5 business days. That is the time we take to process the order and hand it to the carrier. Transit time after that depends on the destination.
About the Airtac BSAI Locking Clamp Cylinder BSAI40X25
The AirTAC BSAI40X25 is a double-acting ISO 15552 profile cylinder featuring a spring-applied, air-released clamp-lock mechanism. A defining characteristic of this series is its ability to lock the piston rod at any position along its 25 mm stroke, providing a static holding force of 900 N. The clamp operates bidirectionally, securely holding the load whether the rod was extending or retracting. Operating at 0.15-0.7 MPa, it delivers 628 N of push thrust and 528 N of pull thrust at 0.5 MPa.
It is critical to distinguish between the cylinder thrust and the clamp holding force; the 900 N holding force is a separate static rating that must be sized against your load, independent of the 628 N pneumatic thrust. The clamp utilizes a third G1/8 enclasp port to release the rod, requiring balanced air pressure on both sides of the piston to unlock safely. Furthermore, the variable air cushion at the stroke ends only decelerates the piston; the mechanical clamp is the sole device responsible for holding the load.
Airtac BSAI Locking Clamp Cylinder BSAI40X25 Technical Specifications
| Model | Airtac BSAI Locking Clamp Cylinder BSAI40X25 |
|---|---|
| Series | BSAI ISO 15552 clamp-lock cylinder |
| Bore size | Ø40 mm |
| Stroke | 25 mm |
| Type | Single rod (BSAI), double acting |
| Cylinder port | G1/4 |
| Rod thread | M12×1.25 |
| Lock type | Spring-applied, air-released clamp (any position) |
|---|---|
| Static holding force | 900 N |
| Enclasp / unlock port | G1/8 |
| Operating pressure | 0.15 – 0.7 MPa |
| Temperature | -20 to +70 °C |
| Speed range | 30 – 800 mm/s |
| Max stroke | Up to 800 mm |
Specifications follow the official AirTAC BSAI datasheet (ISO 15552). Operating pressure is 0.15–0.7 MPa (lower than a plain SAI). Port options: PT / G.
How the Clamp-Lock Holds
static holding force (Ø40 mm)
A spring-applied gripper clamps the rod and holds the load at any position in the stroke — not just at the stroke end (that is a SAIL) — and it is bidirectional: it holds whether the rod was extending or retracting.
Theoretical Output Force (Ø40mm)
| Pressure | Push force | Pull force |
|---|---|---|
| 0.5 MPa | 628 N | 528 N |
| 0.7 MPa (max) | 880 N | — |
Push/pull as tabulated. Rated to the 0.7 MPa operating maximum for this series. The clamp holding force (900 N) is separate from cylinder thrust. Size with a margin.
Where the Airtac BSAI Locking Clamp Cylinder BSAI40X25 Is Used
Vertical Axis Mid-Stroke Hold
Maintains a 900 N vertical load securely at any point along the short 25 mm travel without relying on continuous air pressure.
Emergency Power-Loss Hold
The spring-applied clamp engages instantly upon loss of air pressure, freezing the rod exactly where it stopped to prevent load dropping.
Machining Position Lock
Secures a workpiece at a precise intermediate location for a machining or inspection process, ensuring zero unwanted rod movement.
Is the Airtac BSAI Locking Clamp Cylinder BSAI40X25 the Right Clamp-Lock?
Choose this BSAI40X25 when an application requires holding a load at a specific intermediate position, a capability where it outperforms a SAIL cylinder that only locks at stroke ends. If your process only requires end-of-stroke holding, a plain SAI cylinder suffices. To adjust your thrust class, stepping down to a bore 32 provides 402 N push thrust and 600 N holding force, while stepping up to a bore 50 yields 982 N thrust and 1400 N holding force.
When replacing or specifying this unit, match the single-rod configuration, 40 mm bore, 25 mm stroke, and PT port threads. The 16 mm rod and M12x1.25 thread offer robust side-load capacity for short strokes. Mounting options include Basic, FA, FB, CA, CB, CR, LB, TC, TCM1, and TCM2. Note that the clamp locks only after the cylinder has stopped; it cannot brake a moving rod. Safety-critical applications require an additional independent safety measure, and the clamp must be unlocked with balanced pressures to prevent the rod from jumping abruptly.
Quick checklist
- ✓ Hold needed at any position?
- ✓ Or stroke-end only → use SAIL
- ✓ Holding force ≥ your load
- ✓ Balanced-pressure unlock circuit
- ✓ Extra safety measure for people
Airtac BSAI Locking Clamp Cylinder BSAI40X25 FAQ
The BSAI40X25 provides a static holding force of 900 N. This bidirectional clamp can engage at any position along the 25 mm stroke, but it only locks after the piston has come to a complete stop.
The clamp is released via a third G1/8 enclasp port, but only after the air pressures on both sides of the piston are balanced. If pressures are not balanced, the rod may move abruptly upon release, so an external safety measure is advised for human-safety applications.
Related AirTAC Lock & Standard Cylinders
Request a Quote for Airtac BSAI Locking Clamp Cylinder BSAI40X25
Send us the quantity and destination. We confirm price, stock and lead time — usually within 7-8 hours.