This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40X210S, 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 SI40X210S
The AirTAC Airtac SI40 Standard Cylinder SI40X210S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 210mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40X210S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke210 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40X210S
- 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 SI40X210S
The AirTAC SI40X210S is a discontinued double-acting ISO 15552 profile cylinder with a 40 mm bore and 210 mm stroke. It delivers 628 N push force at 0.5 MPa via a G1/4 port. AirTAC replaced this legacy unit with the SAI40X210S, a direct sharing the exact interface, bore, stroke, force and mounting.
The SAI upgrade features two Y-shaped one-way piston seals for low start-up pressure and long life. The SI -S magnet works with CS1-B/DS1-B sensors, while the SAI family adds lock variants like SAIL and BSAI that the SI lacked.
Airtac SI40 Standard Cylinder SI40X210S Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40X210S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40X210S |
| Bore size | Ø40 mm |
| Stroke | 210 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 SAI40X210S 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 SAI40X210S 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 SI40X210S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×210 | 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 SI40X210S Is Used
Component Ejection
Pushes machined parts out of a CNC fixture using 628 N of force at 0.5 MPa, relying on the 210 mm stroke to clear the work envelope completely.
Package Diverting
Actuates a routing gate on a packaging line, where the G1/4 port and 30-800 mm/s speed range provide rapid, repetitive cycling.
Pallet Stopping
Deploys a physical stop block for inbound pallets, safely absorbing kinetic energy using the adjustable 27 mm air cushions at both ends.
Replacing the Airtac SI40 Standard Cylinder SI40X210S with the SAI40X210S
To replace the SI40X210S, order the SAI40X210S. Verify the ISO 15552 mounting interface, 40 mm bore, 210 mm stroke, G1/4 port (PT/G/NPT thread options) and the -S magnet for current AirTAC switches. Sizing both ways: a 32 mm bore yields 402 N push at 0.5 MPa, while a 50 mm bore yields 982 N. If you need to hold a load vertically without live air, note that a plain cylinder drifts and the air cushion only decelerates; use an external rod lock, pilot check valve, or the SAIL/BSAI lock variant. At 210 mm stroke, side-load and rod-bending risks are low, but ensure guide alignment to prevent seal wear.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40X210S
- ✓ 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 SI40X210S FAQ
Yes, the AirTAC SI40X210S is discontinued. The direct replacement is the SAI40X210S. It is dimensionally interchangeable per ISO 15552, retaining the same 40 mm bore, 210 mm stroke, output force, G1/4 port and mounting accessories.
The G1/4 port feeds a 16 mm rod. Force output is 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. Speed is 30-800 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40X210S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40X210S replacement — usually within 7-8 hours.