Airtac SAILB Rear Lock Cylinder SAILB40X150
The AirTAC Airtac SAILB Rear Lock Cylinder SAILB40X150 is a genuine double-acting ISO 15552 profile cylinder with a Ø40mm bore, 150mm 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
- Stroke150 mm
- Port sizeG1/4
- Lock positionBack cover
- Rod threadM12×1.25
- UnlockAir + manual
About the Airtac SAILB Rear Lock Cylinder SAILB40X150
The AirTAC SAILB40X150 is a double-acting ISO 15552 profile cylinder featuring a spring-applied, air-released mechanical lock integrated into the back cover. This mechanism engages automatically when the piston reaches the retracted stroke end, securely holding the rod and load without requiring continuous live air pressure. In the 40mm bore class, it generates 628N of push force and 528N of pull force at 0.5 MPa, making it well-suited for compact load-holding tasks.
A key design detail is that the variable air cushion at the locker end is notably shorter (20mm) compared to the free end (27mm), ensuring the locking pin engages properly without excessive deceleration travel. The lock is a static holding device, not a dynamic brake, and is released automatically by supplying air to the release port or manually via the override lever. For position sensing, the barrel features dual sensor grooves compatible with AirTAC CMSE reed and DMSE electronic switches when a magnet is specified.
Airtac SAILB Rear Lock Cylinder SAILB40X150 Technical Specifications
| Model | Airtac SAILB Rear Lock Cylinder SAILB40X150 |
|---|---|
| Series | SAIL ISO 15552 cylinder with lock |
| Bore size | Ø40 mm |
| Stroke | 150 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 SAILB40X150 Is Used
Vertical Load Holding
Secures elevated loads at the retracted stroke end during power loss, preventing gravity-induced drops in lifting jigs.
End-Stroke Clamping
Holds a workpiece firmly in place at the rod-in terminal position without consuming compressed air during the hold.
Safety Gate Hold
Keeps heavy safety gates or guards locked closed until air is actively supplied to release the internal lock pin.
Is the Airtac SAILB Rear Lock Cylinder SAILB40X150 the Right Lock Cylinder?
Select this 40mm bore model when your application requires a fail-safe hold at the retracted position with moderate force; if you need higher thrust, stepping up to the 50mm bore yields 825N of pull at 0.5 MPa. Choose the SAILB configuration specifically when the load must be secured in the rod-in direction, whereas the SAILF variant holds at the extended stroke end. If your machinery requires clamping at an arbitrary mid-stroke position rather than the stroke terminal, the AirTAC BSAI clamp-lock cylinder is the correct alternative.
Because the lock holds statically only at the stroke end, never attempt to use it to stop a moving rod. Valve selection is critical: do not use a fast-exhaust valve with this cylinder, as back-pressure on the locker side can unintentionally release the lock—always use an independent-exhaust solenoid valve. For safety-critical lifting applications where human safety depends on the load staying up, always add an independent secondary safety measure. Replacement matches require 40mm bore, 150mm stroke, back locker position, PT tapered ports, and standard carbon steel rod material.
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 SAILB40X150 FAQ
At 0.5 MPa operating pressure, the 40mm bore generates 628N of push force and 528N of pull force. The maximum thrust is 128 kgf at 1.0 MPa.
The lock is spring-applied and air-released, engaging statically only when the piston reaches the retracted stroke end in the back cover. It does not clamp at mid-stroke, and it is released automatically via air pressure or manually via a lever.
Related AirTAC Lock & Standard Cylinders
Request a Quote for Airtac SAILB Rear Lock Cylinder SAILB40X150
Send us the quantity and destination. We confirm price, stock and lead time — usually within 7-8 hours.