This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40X126, 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 SI40X126
The AirTAC Airtac SI40 Standard Cylinder SI40X126 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 126mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40X126, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke126 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40X126
- 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 SI40X126
The AirTAC SI40X126 is a discontinued double-acting ISO 15552 profile cylinder with a 40 mm bore and 126 mm stroke. It delivers 628 N push force at 0.5 MPa via a G1/4 port. Because this exact stroke is non-standard, the direct is the current-production SAI40X126, which matches the interface, bore, force and mounting.
The SAI40X126 features an upgraded piston seal with two Y-shaped one-way elements for low start-up pressure and long life. Note this non-magnet SKU cannot hold a sensor; for load holding use the SAIL lock or BSAI clamp-lock variant.
Airtac SI40 Standard Cylinder SI40X126 Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40X126 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40X126 |
| Bore size | Ø40 mm |
| Stroke | 126 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 SAI40X126 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 SAI40X126 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 SI40X126
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×126 | 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 SI40X126 Is Used
Mid-Force Clamping
Secures workpieces in machining fixtures using 628 N of push force at 0.5 MPa.
Package Diversion
Actuates routing gates on packaging lines with a 126 mm non-standard stroke.
Replacing the Airtac SI40 Standard Cylinder SI40X126 with the SAI40X126
To replace the SI40X126, order the SAI40X126. Confirm the ISO 15552 mounting interface, the 40 mm bore, the 126 mm non-standard stroke, the G1/4 port (PT/G/NPT), and your mounting accessory. This non-magnet SKU cannot take a CS1-B or DS1-B sensor. If sizing up or down, neighboring bores are 32 mm (402 N push @0.5 MPa) and 50 mm (982 N push @0.5 MPa). A plain cylinder drifts on air loss—the cushion only decelerates—so for load holding use an external rod lock, pilot check valve, or the SAIL/BSAI lock variants. As the 126 mm stroke exceeds 300 mm? No, but any stroke over 300 mm requires a guide to prevent rod bending.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40X126
- ✓ 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 SI40X126 FAQ
Yes, the SI40X126 is discontinued. The direct replacement is the SAI40X126. It is dimensionally interchangeable per ISO 15552, retaining the same 40 mm bore, 126 mm stroke, G1/4 port, and mounting interface.
The G1/4 port feeds a 16 mm rod. Forces 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 max of 128 kgf at 1.0 MPa.
Request a Quote for the SAI40X126
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40X126 replacement — usually within 7-8 hours.