Airtac SAILF Front Locking Pneumatic Cylinder SAILF50X125S
The AirTAC Airtac SAILF Front Locking Pneumatic Cylinder SAILF50X125S is a genuine double-acting ISO 15552 profile cylinder with a Ø50mm bore, 125mm 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.
- BoreØ50 mm
- Stroke125 mm
- Port sizeG1/4
- Lock positionFront cover
- Rod threadM16×1.5
- 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 SAILF50X125S
The AirTAC SAILF50X125-S is a double-acting ISO 15552 profile cylinder equipped with a spring-applied, air-released mechanical lock housed in the front cover. Because the lock engages when the piston reaches the extended stroke end, it securely holds the rod-out position without requiring continuous live pressure. In the 50mm bore class, this actuator generates 982N of push force and 825N of pull force at 0.5 MPa, making it well-suited for medium-duty holding tasks. A carbon steel rod provides durable service, and the integrated -S magnet enables precise position tracking using CMSE reed or DMSE solid-state sensors.
This model features a 1/4 PT tapered port and variable air cushions at both ends to manage deceleration. The cushion at the locker end is 20mm, which is shorter than the 30mm cushion on the free end, an intentional design choice to accommodate the locking mechanism. The lock itself is a static holding device that engages after the cylinder stops; it is not a dynamic brake for a moving rod. If your process requires clamping at an arbitrary mid-stroke point rather than the extended terminal, you should select the BSAI clamp-lock cylinder instead.
Airtac SAILF Front Locking Pneumatic Cylinder SAILF50X125S Technical Specifications
| Model | Airtac SAILF Front Locking Pneumatic Cylinder SAILF50X125S |
|---|---|
| Series | SAIL ISO 15552 cylinder with lock |
| Bore size | Ø50 mm |
| Stroke | 125 mm |
| Acting type | Double acting, with lock |
| Port size | G1/4 |
| Rod thread | M16×1.5 |
| 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 – 800 mm/s |
| Cushion | Adjustable (30 mm free end / 20 mm lock end) |
| Max stroke | Up to 1200 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 (Ø50mm)
| Pressure | Push force | Pull force |
|---|---|---|
| 0.5 MPa | 982 N | 825 N |
| 0.7 MPa | 1374 N | — |
| Max (@1.0 MPa) | 200 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 SAILF50X125S Is Used
Vertical Lift Safety
Holds an extended vertical load securely in place automatically during a compressed air failure or power loss event.
Extended Clamp Hold
Maintains outward clamping pressure at the extended stroke end without consuming continuous air pressure.
Gate Position Retention
Secures an automated conveyor gate in the open rod-out position, preventing unintended closure during maintenance.
Is the Airtac SAILF Front Locking Pneumatic Cylinder SAILF50X125S the Right Lock Cylinder?
Select this 50mm bore model when an application demands 982N of thrust at 0.5 MPa and must maintain a rod-out position upon air loss. If your setup requires less force, stepping down to a 40mm bore yields 628N of push force, while moving up to a 63mm bore provides 1559N for heavier loads. Choose the SAILF front-locker variant to hold the extended stroke end, and pick the SAILB back-locker variant if the retracted position must be secured instead.
When specifying this cylinder, remember the lock holds statically only at the stroke terminal. Never use a fast-exhaust valve with this lock cylinder, as back-pressure on the locker side can unintentionally release the mechanism; always use an independent-exhaust solenoid valve. For safety-critical loads that could endanger personnel if they fall, add an independent mechanical safety measure alongside the lock. To replace this unit, match the 50mm bore, 125mm stroke, front locker position, 1/4 PT port, and the -S magnet requirement.
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 SAILF50X125S FAQ
At an operating pressure of 0.5 MPa, this 50mm bore cylinder generates 982N of push force and 825N of pull force. At 0.7 MPa, the push force increases to 1374N.
The lock is spring-applied and air-released, engaging automatically once the rod reaches the extended stroke end in the front cover. To unlock it, you supply air to the release port or use the manual release lever. It provides a static hold only at the stroke terminal and does not clamp mid-stroke.
Related AirTAC Lock & Standard Cylinders
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