This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40BX210, 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 SI40BX210
The AirTAC Airtac SI40 Standard Cylinder SI40BX210 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 SAI40BX210, 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 → SAI40BX210
- 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 SI40BX210
The AirTAC SI40BX210 is a discontinued double-acting ISO 15552 profile cylinder with a 40mm bore and 210mm stroke. Featuring a SUS304 stainless steel rod and G1/4 port, it delivers 628 N push force at 0.5 MPa. The direct replacement is the SAI40BX210, which matches the exact bore, stroke, force, port, and ISO 15552 mounting interface.
The SAI upgrade introduces a two Y-shaped one-way piston seal for low start-up pressure and extended life. Because this specific SKU lacks the -S magnet, it cannot accept legacy CS1-B/DS1-B sensors.
Airtac SI40 Standard Cylinder SI40BX210 Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40BX210 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40BX210 |
| 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 SAI40BX210 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 SAI40BX210 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 SI40BX210
| 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 SI40BX210 Is Used
Stainless Rod Diverters
Ideal for pushing lightweight packages on packaging lines where the SUS304 rod resists moisture and corrosion.
Medium Force Actuators
Provides reliable 628 N push force for clamping medium workpieces or positioning tooling fixtures in machining centers.
Replacing the Airtac SI40 Standard Cylinder SI40BX210 with the SAI40BX210
To replace the discontinued SI40BX210, order the SAI40BX210 and confirm the ISO 15552 mounting interface, 40mm bore, 210mm stroke, G1/4 port, and SUS304 rod material. When sizing, note the 40mm bore yields 628 N push at 0.5 MPa, whereas stepping up to a 50mm bore provides 982 N. Since the 210mm stroke exceeds 300mm? No, but at 210mm you should still verify guide alignment to prevent rod bending. This non-magnetic SKU cannot support position sensing. For load holding on air loss, note the cushion only decelerates; use an external pilot check valve or explore the SAIL or BSAI lock variants.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40BX210
- ✓ 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 SI40BX210 FAQ
Yes, the SI40BX210 is discontinued. The direct replacement is the SAI40BX210. It features the same ISO 15552 mounting interface, 40mm bore, 210mm stroke, G1/4 port, and force ratings, fitting directly into existing fixtures.
This double-acting cylinder has a G1/4 port. The 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.
Related AirTAC SAI Cylinders
Request a Quote for the SAI40BX210
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40BX210 replacement — usually within 7-8 hours.