This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40X135S, 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 SI40X135S
The AirTAC Airtac SI40 Standard Cylinder SI40X135S 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 SAI40X135S, 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 → SAI40X135S
- 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 SI40X135S
The AirTAC SI40X135S 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. The direct replacement is the SAI40X135S, matching the interface, bore, stroke, force, and mounting.
The SAI upgrade features a two Y-shaped one-way piston seal for low start-up pressure and long life. The SI -S magnet works with legacy CS1-B/DS1-B sensors, while SAI uses current AirTAC switches.
Airtac SI40 Standard Cylinder SI40X135S Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40X135S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40X135S |
| 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 SAI40X135S 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 SAI40X135S 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 SI40X135S
| 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 SI40X135S Is Used
Component Clamping
Secures medium-weight machined parts during milling or drilling, utilizing the 628 N push force to hold firm against cutting vibration.
Package Diverting
Actuates routing gates on packaging lines, providing reliable 135 mm stroke movement to redirect boxes at sorting stations.
Pallet Stopper
Functions as a pneumatic stop mechanism in conveyor endpoints, arresting pallets smoothly using adjustable end cushions.
Replacing the Airtac SI40 Standard Cylinder SI40X135S with the SAI40X135S
To replace the SI40X135S, order the SAI40X135S. Confirm the ISO 15552 mounting interface, 40 mm bore, 135 mm stroke, G1/4 port (PT/G/NPT), and mounting accessory. The -S denotes a piston magnet for position sensing. If sizing up or down, the adjacent 32 mm bore yields 402 N push at 0.5 MPa, while the 50 mm bore yields 982 N. A plain cylinder drifts on air loss; the cushion only decelerates. For load holding, use an external rod lock, pilot check valve, or the SAIL/BSAI lock variants. At 135 mm stroke, side-load and rod-bending risks are low, but ensure proper guide alignment.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40X135S
- ✓ 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 SI40X135S FAQ
Yes, the AirTAC SI40X135S is discontinued. The direct replacement is the SAI40X135S. It is dimensionally interchangeable per ISO 15552, retaining the exact same 40 mm bore, 135 mm stroke, 628 N force, G1/4 port, and mounting interface.
The 40 mm bore cylinder operates at 30-800 mm/s. Force ratings are: 628 N push and 528 N pull at 0.5 MPa, 879 N push at 0.7 MPa, 1130 N push at 0.9 MPa, and a theoretical maximum of 128 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40X135S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40X135S replacement — usually within 7-8 hours.