Airtac SAILF Front Locking Pneumatic Cylinder SAILF40X300
The AirTAC Airtac SAILF Front Locking Pneumatic Cylinder SAILF40X300 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 SAILF40X300
The AirTAC SAILF40X300 is a double-acting ISO 15552 profile cylinder featuring a built-in mechanical lock housed within the front cover. Because the lock is spring-applied and air-released, cutting the release air immediately drives a lock pin into the rod, securely holding the load at the extended stroke end without relying on live pressure. In this 40mm bore class, the cylinder delivers 879N of push force at 0.7 MPa, making it suitable for moderate load-holding tasks. Unlocking is achieved automatically by supplying air to the release port or by utilizing the manual release lever.
A key mechanical detail is that the variable air cushion at the locker end is notably shorter (20mm) compared to the free end cushion (27mm). This cylinder uses a carbon steel rod and PT tapered port threads. For position sensing, you can fit AirTAC CMSE reed or DMSE electronic sensors into the dual-side barrel grooves if a magnet is specified. Remember that the lock engages only after the piston reaches the extended terminal, acting as a static hold rather than a dynamic mid-stroke clamp.
Airtac SAILF Front Locking Pneumatic Cylinder SAILF40X300 Technical Specifications
| Model | Airtac SAILF Front Locking Pneumatic Cylinder SAILF40X300 |
|---|---|
| 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 SAILF40X300 Is Used
Vertical Load Holding
Secures elevated loads at the extended stroke end automatically when air pressure drops, preventing sudden drops.
Power Failure Safety
Maintains a safely extended position during power outages, requiring an independent safety measure for human safety.
Extended Clamp Secure
Holds a clamped workpiece firmly at the rod-out terminal without consuming continuous live air pressure.
Is the Airtac SAILF Front Locking Pneumatic Cylinder SAILF40X300 the Right Lock Cylinder?
Choose this 40mm bore model when a load must be securely maintained at the extended stroke end during a power loss. If your application requires less force, stepping down is not an option as SAIL skips a 32mm bore, but stepping up to the 50mm bore yields 1374N of push force at 0.7 MPa. If the load must be clamped at an arbitrary mid-stroke position rather than the extended end, select the BSAI clamp-lock cylinder instead.
For safe operation, never use a fast-exhaust valve with this lock cylinder; always select an independent-exhaust solenoid valve, as back-pressure on the locker side can inadvertently release the lock. At a 300mm stroke, adding an external guide is recommended to prevent excessive side-load wear on the rod. To match this cylinder for a replacement, verify the 40mm bore, 300mm stroke, front locker position, 1/4 PT port, and standard carbon steel rod.
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 SAILF40X300 FAQ
The 40mm bore generates 628N of push force at 0.5 MPa and 879N at 0.7 MPa. The pull force is 528N at 0.5 MPa.
The lock is spring-applied and air-released, engaging only when the piston reaches the extended stroke end. It provides a static hold, not a dynamic brake, and is unlocked automatically via air or manually via a lever.
Related AirTAC Lock & Standard Cylinders
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