Airtac SAILB Rear Lock Cylinder SAILB63X350
The AirTAC Airtac SAILB Rear Lock Cylinder SAILB63X350 is a genuine double-acting ISO 15552 profile cylinder with a Ø63mm bore, 350mm 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
- Stroke350 mm
- Port sizeG3/8
- Lock positionBack cover
- Rod threadM16×1.5
- UnlockAir + manual
About the Airtac SAILB Rear Lock Cylinder SAILB63X350
The AirTAC SAILB63X350 is a double-acting ISO 15552 profile cylinder featuring a spring-applied, air-released mechanical lock integrated into the back cover. This lock engages automatically when the piston reaches the retracted stroke end, securely holding a load without requiring continuous live air pressure. With a 63mm bore, it generates 1559N of push force and 1402N of pull force at 0.5 MPa, making it well-suited for mid-weight vertical holding tasks where energy conservation and power-loss safety are critical.
The cylinder features a carbon steel piston rod and PT tapered port threads. Because the lock mechanism occupies space in the back cover, the variable air cushion on that locker end is notably shorter at 21mm compared to the 30mm cushion on the free end. The lock releases automatically via air supply or manually via a lever, but avoid using fast-exhaust valves, as back-pressure on the locker side can unintentionally release the lock.
Airtac SAILB Rear Lock Cylinder SAILB63X350 Technical Specifications
| Model | Airtac SAILB Rear Lock Cylinder SAILB63X350 |
|---|---|
| Series | SAIL ISO 15552 cylinder with lock |
| Bore size | Ø63 mm |
| Stroke | 350 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 SAILB63X350 Is Used
Vertical Lift Holding
Maintains a raised load securely at the retracted stroke end during air pressure loss or emergency stops on lifting machinery.
Conveyor Stop Gate
Locks a stop gate in the retracted position without consuming continuous air, releasing automatically when the release port is pressurized.
Clamp and Hold Fixture
Provides a reliable static hold at the stroke terminal for clamping fixtures, ensuring the workpiece remains secured without live pressure.
Is the Airtac SAILB Rear Lock Cylinder SAILB63X350 the Right Lock Cylinder?
Select this 63mm bore model when an application requires holding a load at the fully retracted position; if you need the load held at the extended rod-out position, choose the SAILF variant instead. If your application demands clamping at an arbitrary mid-stroke point rather than a stroke-end static hold, the AirTAC BSAI clamp-lock cylinder is the correct choice. For higher force requirements, stepping up to an 80mm bore provides 2513N push at 0.5 MPa, while dropping to a 50mm bore reduces the force to 982N.
When replacing this cylinder, verify the 350mm stroke, back locker position, 3/8 port size, and ISO 15552 mounting interface. Standard strokes for this bore extend up to 1500mm. Because the stroke is 350mm, incorporating external guide rails is recommended to prevent excessive side loads from damaging the rod seals. For safety-critical lifting applications that could endanger personnel if the load drops, always add an independent mechanical safety measure alongside the lock.
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 SAILB63X350 FAQ
At a 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, engaging statically once the piston stops at the retracted stroke end. It does not brake a moving rod or hold at mid-stroke. Unlocking is done automatically by supplying air to the release port or by using the manual release lever.
Related AirTAC Lock & Standard Cylinders
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