Airtac SAILB Rear Lock Cylinder SAILB200X125
The AirTAC Airtac SAILB Rear Lock Cylinder SAILB200X125 is a genuine double-acting ISO 15552 profile cylinder with a Ø200mm bore, 125mm 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.
- BoreØ200 mm
- Stroke125 mm
- Port sizeG3/4
- Lock positionBack cover
- Rod threadM36×2
- UnlockAir + manual
About the Airtac SAILB Rear Lock Cylinder SAILB200X125
The AirTAC SAILB200X125 is a double-acting ISO 15552 profile cylinder featuring a spring-applied, air-released mechanical lock housed in the back cover. Because the lock engages when the piston reaches the retracted stroke end, it safely holds heavy vertical loads without requiring continuous live air pressure. In this 200mm bore class, the carbon steel rod generates a pull force of 15080N at 0.5MPa, making it highly capable for substantial weight management.
A key mechanical detail is that the variable air cushion at the locker end is shorter (28mm) than the free end cushion (50mm), deliberately accommodating the lock hardware. For position sensing, adding a -S magnet allows the use of AirTAC CMSE reed or DMSE solid-state sensors in the dual-side barrel grooves. The lock unlocks automatically via supplied release air or through a manual override lever.
Airtac SAILB Rear Lock Cylinder SAILB200X125 Technical Specifications
| Model | Airtac SAILB Rear Lock Cylinder SAILB200X125 |
|---|---|
| Series | SAIL ISO 15552 cylinder with lock |
| Bore size | Ø200 mm |
| Stroke | 125 mm |
| Acting type | Double acting, with lock |
| Port size | G3/4 |
| Rod thread | M36×2 |
| 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 – 500 mm/s |
| Cushion | Adjustable (50 mm free end / 28 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 (Ø200mm)
| Pressure | Push force | Pull force |
|---|---|---|
| 0.5 MPa | 15708 N | 15080 N |
| 0.7 MPa | 21991 N | — |
| Max (@1.0 MPa) | 3204 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 SAILB200X125 Is Used
Press Extraction
Holds a heavy 200mm bore press ram securely in the retracted position during power loss, preventing accidental descent while operators clear jams.
Heavy Mold Clamping
Locks an industrial mold base at the retracted stroke end without continuous air consumption, ensuring the mold stays open during maintenance.
Vertical Safety Gate
Maintains a massive safety barrier in the open, retracted position by engaging the mechanical lock, guaranteeing the gate fails safely if air pressure drops.
Is the Airtac SAILB Rear Lock Cylinder SAILB200X125 the Right Lock Cylinder?
Select this 200mm bore model when an application demands extreme holding power at the retracted position, stepping up from the 160mm bore which yields 9425N of pull at 0.5MPa. Choose the SAILB configuration specifically because the load must be secured at the rod-in stroke end; if the process requires holding the load at the extended position, the SAILF variant is required instead. Furthermore, if the mechanism needs to lock at an arbitrary mid-stroke point rather than a stroke end, the BSAI clamp-lock cylinder is the correct solution.
Remember that this lock is a static holding device, not a dynamic brake for a moving rod. Avoid using fast-exhaust valves with this cylinder, as back-pressure on the locker side can unintentionally release the lock; an independent-exhaust solenoid valve is mandatory. For any safety-critical load that could endanger personnel if it drops, always add an independent mechanical safety measure. Replacement matches require the exact 200mm bore, 125mm stroke, back locker position, PT port threads, and appropriate mounting accessories.
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 SAILB200X125 FAQ
The 200mm bore generates a push force of 15708N and a pull force of 15080N at 0.5MPa. At the maximum operating pressure of 1.0MPa, it achieves a maximum push force of 3204kgf.
The lock is spring-applied and air-released, located in the back cover to hold the rod at the retracted stroke end. It engages statically after the cylinder stops and can be released automatically via air pressure or manually via a lever. It does not clamp at mid-stroke.
Related AirTAC Lock & Standard Cylinders
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