Airtac SAILB Rear Lock Cylinder SAILB63X25
The AirTAC Airtac SAILB Rear Lock Cylinder SAILB63X25 is a genuine double-acting ISO 15552 profile cylinder with a Ø63mm bore, 25mm stroke and a built-in spring-applied, air-released mechanical lock in the back cover — it holds the load at the retracted (rod-in) stroke end even when air is lost.
- BoreØ63 mm
- Stroke25 mm
- Port sizeG3/8
- Lock positionBack cover
- Rod threadM16×1.5
- UnlockAir + manual
About the Airtac SAILB Rear Lock Cylinder SAILB63X25
The AirTAC SAILB63X25 is a double-acting ISO 15552 profile cylinder featuring a spring-applied, air-released mechanical lock housed in the back cover. This built-in mechanism holds the rod securely at the retracted stroke end, dropping the load safely upon air pressure loss. In the 63mm bore class, it generates 1559N of push force and 1402N of pull force at 0.5 MPa.
A key design trait is the shorter variable air cushion at the locker end (21mm) compared to the free end (30mm), accommodating the lock hardware without sacrificing end-of-stroke deceleration. The lock engages statically after the piston stops; it is not a dynamic brake. For position sensing, adding a -S magnet enables tracking with AirTAC CMSE reed or DMSE electronic sensors.
Airtac SAILB Rear Lock Cylinder SAILB63X25 Technical Specifications
| Model | Airtac SAILB Rear Lock Cylinder SAILB63X25 |
|---|---|
| Series | SAIL ISO 15552 cylinder with lock |
| Bore size | Ø63 mm |
| Stroke | 25 mm |
| Acting type | Double acting, with lock |
| Port size | G3/8 |
| Rod thread | M16×1.5 |
| Lock type | Spring-applied, air-released (back cover) |
|---|---|
| Unlock | Automatic (air) & manual |
| Operating pressure | 0.15 – 1.0 MPa |
| Temperature | -20 to +70 °C |
| Speed range | 30 – 800 mm/s |
| Cushion | Adjustable (30 mm free end / 21 mm lock end) |
| Max stroke | Up to 1500 mm |
Specifications follow the official AirTAC SAIL datasheet (ISO 15552). Confirm against the product label before installation. Port options: PT / G.
How the Lock Holds
The lock is spring-applied and air-released: a spring drives a lock pin into the rod when the release air is removed, so the load is held at the retracted (rod-in) stroke end without live pressure. Supply air to the release port to unlock automatically, or use the manual release lever.
The lock engages only when the piston reaches the stroke terminal on the back-cover side — it is a static end-of-stroke hold, not a mid-stroke clamp and not a moving-rod brake. For locking at any position along the stroke, choose a BSAI clamp-lock instead.
Theoretical Output Force (Ø63mm)
| Pressure | Push force | Pull force |
|---|---|---|
| 0.5 MPa | 1559 N | 1402 N |
| 0.7 MPa | 2182 N | — |
| Max (@1.0 MPa) | 318 kgf | |
Cylinder thrust is separate from the lock's holding capability. Actual usable force is lower than theoretical due to friction and back-pressure — size with a margin.
Where the Airtac SAILB Rear Lock Cylinder SAILB63X25 Is Used
Vertical Lift Safety
Holds a lifted vertical load securely in the retracted position during a power loss event, preventing sudden drops.
Clamp and Hold
Maintains clamping force at the retracted stroke end without consuming continuous live air pressure.
Gate Guarding
Keeps safety gates and heavy barriers locked shut in the retracted state until the release air is actively supplied.
Is the Airtac SAILB Rear Lock Cylinder SAILB63X25 the Right Lock Cylinder?
Choose this 63mm bore when an application requires 1559N thrust at 0.5 MPa, stepping up from a 50mm bore (982N push) or down from an 80mm bore (2513N push). Select the SAILB configuration when the load must be held in the retracted position; choose SAILF instead if the extended rod-out end requires holding. If your process demands clamping at an arbitrary mid-stroke point, the BSAI clamp-lock cylinder is the correct choice instead of SAIL.
Ensure safe load holding by avoiding fast-exhaust valves, as back-pressure on the locker side can inadvertently release the lock; use an independent-exhaust solenoid valve. For critical human-safety loads, add an independent mechanical safety measure. Replacement specifications must match the 63mm bore, 25mm stroke, back locker position, 3/8 PT port, and standard carbon steel rod.
Quick checklist
- ✓ Hold needed at the retracted (rod-in) end?
- ✓ Or lock anywhere → use BSAI
- ✓ Independent-exhaust valve fitted
- ✓ Port/thread type (PT/G)
- ✓ Extra safety measure for people
Airtac SAILB Rear Lock Cylinder SAILB63X25 FAQ
At 0.5 MPa operating pressure, the 63mm bore provides 1559N of push force and 1402N of pull force. At 0.7 MPa, the push force increases to 2182N.
The lock is spring-applied and air-released, holding the rod statically at the retracted stroke end. It engages only after the cylinder stops and is released automatically via air supply or manually via a lever; it does not clamp at mid-stroke.
Related AirTAC Lock & Standard Cylinders
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