This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40X135, 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 SI40X135
The AirTAC Airtac SI40 Standard Cylinder SI40X135 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 135mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40X135, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke135 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40X135
- 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 SI40X135
The AirTAC SI40X135 is a discontinued double-acting ISO 15552 profile cylinder with a 40 mm bore and 135 mm stroke. It delivers 628 N push force at 0.5 MPa via a G1/4 port. AirTAC replaced this legacy unit with the SAI40X135, a direct upgrade retaining the exact bore, stroke, force, port, and ISO 15552 mounting interface.
The SAI upgrade features a modernized piston seal with two Y-shaped one-way elements for low start-up pressure and extended life. This specific SKU lacks a magnet, meaning it cannot accept a CS1-B or DS1-B sensor.
Airtac SI40 Standard Cylinder SI40X135 Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40X135 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40X135 |
| Bore size | Ø40 mm |
| Stroke | 135 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 SAI40X135 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 SAI40X135 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 SI40X135
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×135 | 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 SI40X135 Is Used
Package Diverting
Actuates routing gates on packaging lines where 628 N push force easily redirects standard cartons.
Clamp Actuation
Secures light workpieces during machining, utilizing the 528 N pull force at 0.5 MPa for reliable hold.
Stopper Arms
Raises and lowers pallet stoppers in material handling zones, with the 135 mm stroke clearing pallet flow.
Replacing the Airtac SI40 Standard Cylinder SI40X135 with the SAI40X135
To replace the SI40X135, order the SAI40X135. Verify your existing fixture matches the ISO 15552 mounting interface dimensions, the G1/4 air port, and the M12x1.25 rod thread. Because this 135 mm stroke is non-standard (falling between the 125 mm and 150 mm standard strokes), confirm the exact extended length fits your assembly. If you need to scale up, the neighboring 50 mm bore provides 982 N push at 0.5 MPa; scaling down, the 32 mm bore offers 402 N. Note that a plain cylinder drifts without live air—the cushion only decelerates at stroke end—so for load holding, consider an external pilot check valve or the SAIL lock variant. This non-magnetic SKU cannot support position sensing.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40X135
- ✓ 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 SI40X135 FAQ
Yes, the SI40X135 is discontinued. The direct replacement is the SAI40X135. It is dimensionally interchangeable per ISO 15552, matching the 40 mm bore, 135 mm stroke, G1/4 port, and mounting accessories.
The G1/4 port feeds a 40 mm bore that generates 628 N push and 528 N pull at 0.5 MPa. At 0.7 MPa push is 879 N, at 0.9 MPa it is 1130 N, and the theoretical maximum is 128 kgf at 1.0 MPa.
Request a Quote for the SAI40X135
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40X135 replacement — usually within 7-8 hours.