Airtac SAILF Front Locking Pneumatic Cylinder SAILF125X25S
The AirTAC SAILF Front Locking Pneumatic Cylinder SAILF125X25S is a genuine double-acting ISO 15552 profile cylinder with a Ø125mm bore, 25mm stroke and a built-in spring-applied, air-released mechanical lock in the front cover — it holds the load at the extended (rod-out) stroke end even when air is lost.
- BoreØ125 mm
- Stroke25 mm
- Port sizeG1/2
- Lock positionFront cover
- Rod threadM27×2
- UnlockAir + manual
- 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 SAILF Front Locking Pneumatic Cylinder SAILF125X25S
The AirTAC SAILF125X25-S is a double-acting ISO 15552 profile cylinder featuring a built-in mechanical lock in the front cover. Because it is a SAILF variant, the spring-applied, air-released lock engages when the piston reaches the extended stroke end, securely holding the rod-out position without requiring live air pressure. At 0.5 MPa, this 125mm bore generates 6136N of push force and 5734N of pull force, making it suitable for heavy-duty holding tasks. The standard carbon steel rod provides robust durability, and the included magnet (-S) enables direct compatibility with AirTAC CMSE reed and DMSE electronic sensors for precise end-of-stroke detection.
This model features a PT tapered port thread and a variable air cushion at both ends. Note that the cushion at the locker end is specifically 24mm, which is shorter than the 40mm cushion found on the free end, accommodating the lock mechanism. The lock releases automatically when supply air is fed to the release port, or manually via the override lever. Remember that this is a static holding lock that engages after the cylinder stops; it is not a dynamic brake for a moving rod.
Airtac SAILF Front Locking Pneumatic Cylinder SAILF125X25S Technical Specifications
| Model | Airtac SAILF Front Locking Pneumatic Cylinder SAILF125X25S |
|---|---|
| Series | SAIL ISO 15552 cylinder with lock |
| Bore size | Ø125 mm |
| Stroke | 25 mm |
| Acting type | Double acting, with lock |
| Port size | G1/2 |
| Rod thread | M27×2 |
| Lock type | Spring-applied, air-released (front cover) |
|---|---|
| Unlock | Automatic (air) & manual |
| Operating pressure | 0.15 – 1.0 MPa |
| Temperature | -20 to +70 °C |
| Speed range | 30 – 500 mm/s |
| Cushion | Adjustable (40 mm free end / 24 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 extended (rod-out) 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 front-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 (Ø125mm)
| Pressure | Push force | Pull force |
|---|---|---|
| 0.5 MPa | 6136 N | 5734 N |
| 0.7 MPa | 8590 N | — |
| Max (@1.0 MPa) | 1251 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 SAILF Front Locking Pneumatic Cylinder SAILF125X25S Is Used
Vertical Load Safety
Holds extended vertical loads securely during power loss or air pressure drops, preventing sudden collapses on lifting fixtures.
Extended Clamp Hold
Maintains maximum clamping force at the rod-out stroke end without consuming continuous compressed air, saving energy.
Gate Safety Interlock
Keeps heavy safety gates and access doors firmly locked in the open position until the release air is actively supplied.
Is the Airtac SAILF Front Locking Pneumatic Cylinder SAILF125X25S the Right Lock Cylinder?
Choose this 125mm bore cylinder when an application demands high force and secure holding at the fully extended position. If your load requires less force, stepping down to the 100mm bore yields 3927N of push force at 0.5 MPa, while stepping up to the 160mm bore provides 10053N for heavier loads. Select the SAILF configuration when the rod must be held out; conversely, choose SAILB to hold the retracted position. If your process requires locking at an arbitrary mid-stroke point rather than the stroke end, the BSAI clamp-lock cylinder is the correct choice instead.
For safe operation, never use a fast-exhaust valve with this lock cylinder, as back-pressure on the locker side can unintentionally release the lock; always use an independent-exhaust solenoid valve. If human safety depends on the load remaining extended, add an independent safety measure as well. When replacing this unit, match the 125mm bore, 25mm stroke, front locker position, PT port thread, and the -S magnet specification.
Quick checklist
- ✓ Hold needed at the extended (rod-out) end?
- ✓ Or lock anywhere → use BSAI
- ✓ Independent-exhaust valve fitted
- ✓ Port/thread type (PT/G)
- ✓ Extra safety measure for people
Airtac SAILF Front Locking Pneumatic Cylinder SAILF125X25S FAQ
At 0.5 MPa, this 125mm bore cylinder provides 6136N of push force and 5734N of pull force. At 0.7 MPa, the push force increases to 8590N.
The lock is spring-applied and air-released, engaging only when the piston reaches the extended stroke end in the front cover. It provides a static hold after the rod stops and unlocks automatically via air supply or manually via a lever; it does not clamp mid-stroke.
Related AirTAC Lock & Standard Cylinders
Request a Quote for Airtac SAILF Front Locking Pneumatic Cylinder SAILF125X25S
Send us the quantity and destination. We confirm price, stock and lead time — usually within 7-8 hours.