Airtac SAILB Rear Lock Cylinder SAILB40X75S
The AirTAC Airtac SAILB Rear Lock Cylinder SAILB40X75S is a genuine double-acting ISO 15552 profile cylinder with a Ø40mm bore, 75mm 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.
- BoreØ40 mm
- Stroke75 mm
- Port sizeG1/4
- Lock positionBack cover
- Rod threadM12×1.25
- UnlockAir + manual
About the Airtac SAILB Rear Lock Cylinder SAILB40X75S
The AirTAC SAILB40X75-S is a double-acting ISO 15552 profile cylinder equipped with a mechanical lock in the back cover, designed to hold the rod securely at the retracted stroke end. It delivers 879N of push force and 528N of pull force at 0.7 MPa, making it suitable for compact automation requiring power-loss safety. The integrated -S magnet enables precise position detection using AirTAC CMSE reed or DMSE electronic solid-state sensors.
This unit utilizes a spring-applied, air-released mechanism: cutting the release air engages the lock pin, holding the load without consuming live pressure, while supplying air to the release port unlocks it automatically. A notable design detail is that the variable air cushion at the locker end is shortened to 20mm compared to 27mm on the free end. The standard carbon steel rod provides robust resistance to side loads, and the PT tapered port threads ensure a reliable, sealed pneumatic connection.
Airtac SAILB Rear Lock Cylinder SAILB40X75S Technical Specifications
| Model | Airtac SAILB Rear Lock Cylinder SAILB40X75S |
|---|---|
| Series | SAIL ISO 15552 cylinder with lock |
| Bore size | Ø40 mm |
| Stroke | 75 mm |
| Acting type | Double acting, with lock |
| Port size | G1/4 |
| Rod thread | M12×1.25 |
| 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 (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 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 (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 SAILB Rear Lock Cylinder SAILB40X75S Is Used
Vertical Retract Safety
Holds a lifted vertical load in the rod-in position automatically when air pressure drops, preventing sudden falls during power loss.
Guard Door Hold
Secures a machine safety gate in the closed retracted position without requiring continuous live air pressure to maintain the clamp.
Clamp and Hold
Maintains a static clamping force at the retracted stroke end for light machining tasks, releasing only when commanded by air pressure.
Is the Airtac SAILB Rear Lock Cylinder SAILB40X75S the Right Lock Cylinder?
Select this 40mm bore cylinder when an application demands a fail-safe hold at the rod-in position, stepping up from smaller actuators or down from a 50mm bore (which provides 1374N push at 0.7 MPa) based on your exact thrust requirements. Choose the SAILB configuration specifically when the retracted stroke end is the safety-critical state; if the extended position must be held instead, the SAILF variant is required. For applications needing the load clamped at an arbitrary mid-stroke point rather than the stroke end, the BSAI clamp-lock cylinder is the correct choice.
The lock is a static holding device that engages after the cylinder stops, not a dynamic brake for a moving rod. Valve selection is critical: do not use a fast-exhaust valve, as back-pressure on the locker side can unintentionally release the lock, so an independent-exhaust solenoid valve is mandatory. If human safety depends on the load staying retracted, always add an independent secondary safety measure. Replacement matching requires verifying the 40mm bore, 75mm stroke, back locker position, PT ports, and the -S magnet option.
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 SAILB40X75S FAQ
At 0.5 MPa, the push force is 628N and the pull force is 528N. At 0.7 MPa, the push force is 879N. The maximum operating pressure is 1.0 MPa.
The lock is spring-applied and air-released, engaging only at the retracted stroke end to provide a static hold without live pressure. It unlocks automatically via air release or manually via a lever, but it cannot hold the rod at a mid-stroke position.
Related AirTAC Lock & Standard Cylinders
Request a Quote for Airtac SAILB Rear Lock Cylinder SAILB40X75S
Send us the quantity and destination. We confirm price, stock and lead time — usually within 7-8 hours.