Airtac SAILF Front Locking Pneumatic Cylinder SAILF40X300S
The AirTAC Airtac SAILF Front Locking Pneumatic Cylinder SAILF40X300S is a genuine double-acting ISO 15552 profile cylinder with a Ø40mm bore, 300mm 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.
- BoreØ40 mm
- Stroke300 mm
- Port sizeG1/4
- Lock positionFront cover
- Rod threadM12×1.25
- 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 SAILF40X300S
The AirTAC SAILF40X300-S is a double-acting ISO 15552 profile cylinder equipped with a spring-applied, air-released mechanical lock in the front cover. This lock engages when the piston reaches the extended stroke end, securely holding the rod out without requiring live pressure. In the 40mm bore class, it generates 879N of push force at 0.7MPa, making it suitable for moderate load-holding tasks. The -S suffix indicates an integrated magnet for position sensing with CMSE reed and DMSE electronic switches.
Because the lock occupies the front cover, the variable air cushion on that locker end is notably shorter at 20mm compared to the 27mm cushion on the free back end. The cylinder features a carbon steel rod and PT tapered port threads. Remember that the lock is a static holding device, not a dynamic brake; it engages only after the cylinder has stopped moving.
Airtac SAILF Front Locking Pneumatic Cylinder SAILF40X300S Technical Specifications
| Model | Airtac SAILF Front Locking Pneumatic Cylinder SAILF40X300S |
|---|---|
| Series | SAIL ISO 15552 cylinder with lock |
| Bore size | Ø40 mm |
| Stroke | 300 mm |
| Acting type | Double acting, with lock |
| Port size | G1/4 |
| Rod thread | M12×1.25 |
| 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 (27 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 (Ø40mm)
| Pressure | Push force | Pull force |
|---|---|---|
| 0.5 MPa | 628 N | 528 N |
| 0.7 MPa | 880 N | — |
| Max (@1.0 MPa) | 128 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 SAILF40X300S Is Used
Vertical Lift Hold
Maintains an elevated load safely at the extended stroke end during a power loss, preventing sudden gravity-driven drops.
Pallet Stop Gate
Locks a conveyor diversion gate in the open rod-out position without consuming continuous air pressure, saving energy.
Clamp and Hold
Secures a machined workpiece at the outward stroke terminal while machining operations complete, ensuring rigid positioning.
Is the Airtac SAILF Front Locking Pneumatic Cylinder SAILF40X300S the Right Lock Cylinder?
Choose this 40mm bore model when your application requires holding a load at the fully extended stroke end on power loss. If you need higher force, stepping up to the 50mm bore increases push thrust to 1374N at 0.7MPa. If your application requires locking at an arbitrary mid-stroke position rather than the stroke end, select the BSAI clamp-lock cylinder instead. For strokes of 300mm or more, always use a external guide mechanism to prevent excessive side-load wear on the seals.
When matching replacements, verify the 40mm bore, 300mm stroke, front lock position, PT port threads, and the -S magnet option. The lock holds the rod statically without live air, but never use a fast-exhaust valve with this cylinder; back-pressure on the locker side can unintentionally release the lock. Always use an independent-exhaust solenoid valve, and add an independent safety measure if human safety depends on the load staying extended.
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 SAILF40X300S FAQ
The 40mm bore generates 628N of push force at 0.5MPa and 879N of push force at 0.7MPa. The maximum operating pressure is 1.0MPa.
The lock is spring-applied and air-released, engaging statically when the piston reaches the extended stroke end. It does not clamp at mid-stroke. You can unlock it automatically by supplying release air to the port or by using the manual release lever.
Related AirTAC Lock & Standard Cylinders
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