This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40X25SLB, with the same bore, stroke, output force, port and mounting, so it fits the same application. The SAI replacement keeps the same ISO 15552 mounting interface, bore, stroke, output force and accessories, so it drops straight into existing fixtures. It is the current-production version of this cylinder with an upgraded piston seal.
Airtac SI40 Standard Cylinder SI40X25SLB
The AirTAC Airtac SI40 Standard Cylinder SI40X25SLB is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 25mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40X25SLB, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke25 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40X25SLB
- 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 SI40 Standard Cylinder SI40X25SLB
The AirTAC SI40X25SLB is a discontinued double-acting ISO 15552 profile cylinder with a 40mm bore and 25mm stroke. It delivers 628N push force at 0.5MPa via a G1/4 port. The direct replacement is the SAI40X25SLB, matching the exact ISO 15552 mounting interface, LB foot bracket, and output force.
The SAI upgrade features two Y-shaped one-way piston seals for low start-up pressure and long life. A plain cylinder drifts on air loss; for load holding, use the SAIL lock or a pilot check valve.
Airtac SI40 Standard Cylinder SI40X25SLB Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40X25SLB |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40X25SLB |
| Bore size | Ø40 mm |
| Stroke | 25 mm |
| Acting type | Double acting |
| Port size | G1/4 |
| Rod thread | M12×1.25 |
| Fluid | Air (filtered by 40µm element) |
|---|---|
| Operating pressure | 0.15 – 1.0 MPa |
| Proof pressure | 1.5 MPa |
| Temperature | -20 to +70 °C |
| Speed range | 30 – 800 mm/s |
| Cushion | Adjustable, 27 mm |
| Max standard stroke | Up to 1200 mm |
Specifications follow the official AirTAC SI datasheet (now discontinued). The SAI40X25SLB carries the same ISO 15552 ratings. Confirm against the product label before installation. Thread options: PT / G / NPT.
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 | |
The SAI40X25SLB produces the same force from the same bore. Actual usable force is lower than theoretical; size with a margin.
Model Code: Airtac SI40 Standard Cylinder SI40X25SLB
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×25 | Stroke length in mm. |
| -S | Optional built-in magnet for sensor position sensing. |
Legacy SI-family variants: SID (double rod), SIJ (adjustable stroke) — each maps to its SAI equivalent (SID→SAID, SIJ→SAIJ). Rod material: carbon steel (blank) / SUS420J2 (A) / SUS304 (B).
Where the Airtac SI40 Standard Cylinder SI40X25SLB Is Used
Short-Stroke Clamping
Ideal for holding parts in machining fixtures where a compact 25mm stroke and 628N force securely lock components without consuming excessive space.
Diversion Gate Actuation
Provides rapid routing of items on packaging lines, utilizing the 30-800 mm/s speed range and LB foot mount for stable side-load resistance.
Package Stopper Mechanism
Acts as a pneumatic stop for cartons on rollers, with the magnet enabling CS1-B/DS1-B sensors to confirm the extended position.
Replacing the Airtac SI40 Standard Cylinder SI40X25SLB with the SAI40X25SLB
To replace the SI40X25SLB, order the SAI40X25SLB. Verify the ISO 15552 interface, 40mm bore, 25mm stroke, G1/4 port, LB foot mounting, and the -S magnet for CS1-B/DS1-B sensors. If downsizing, a 32mm bore yields 402N at 0.5MPa; if upsizing, a 50mm bore provides 982N. Remember that standard cylinders do not hold loads without live air—the cushion only decelerates. For locking needs, consider the SAIL or BSAI variants.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40X25SLB
- ✓ Same bore / stroke / force
- ✓ Port/thread type (PT/G/NPT)
- ✓ Magnet (-S) for sensors?
- ✓ Mounting reused (FA/FB/CA/CB/CR/LB/TC)
Airtac SI40 Standard Cylinder SI40X25SLB FAQ
Yes, the SI40X25SLB is discontinued. The direct replacement is the SAI40X25SLB. It shares the same ISO 15552 mounting interface, 40mm bore, 25mm stroke, G1/4 port, and LB foot mount, fitting directly into existing fixtures.
The 40mm bore features a G1/4 port and M12x1.25 rod thread. It delivers 628N push and 528N pull at 0.5MPa, 879N push at 0.7MPa, 1130N push at 0.9MPa, and a theoretical max of 128kgf at 1.0MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40X25SLB
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40X25SLB replacement — usually within 7-8 hours.