This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40BX225, 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 SI40BX225
The AirTAC Airtac SI40 Standard Cylinder SI40BX225 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 225mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40BX225, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke225 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40BX225
- 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 SI40BX225
The AirTAC SI40BX225 is a discontinued double-acting ISO 15552 profile cylinder with a 40mm bore and 225mm stroke. Built with an extruded aluminum barrel, it delivers 628 N push force at 0.5 MPa. The direct replacement is the SAI40BX225, which matches the original G1/4 port, M12x1.25 rod thread, and mounting interface exactly.
This SKU features a SUS304 stainless steel rod for corrosion resistance but lacks a magnet, so it cannot accept position switches. The SAI upgrade utilizes two Y-shaped one-way piston seals for lower start-up pressure.
Airtac SI40 Standard Cylinder SI40BX225 Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40BX225 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40BX225 |
| Bore size | Ø40 mm |
| Stroke | 225 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 SAI40BX225 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 SAI40BX225 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 SI40BX225
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×225 | 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 SI40BX225 Is Used
Package Diverting
Drives diverting arms on packaging lines where the 628 N push force easily shifts cartons at speeds up to 800 mm/s.
Stainless Rod Clamping
The SUS304 rod excels in mildly corrosive clamping tasks, securely holding workpieces during light machining.
Replacing the Airtac SI40 Standard Cylinder SI40BX225 with the SAI40BX225
To replace the SI40BX225, order the SAI40BX225. Verify your ISO 15552 mounting fixtures (LB, FA, TC, etc.), the G1/4 air port, and the 225mm stroke. Because this specific SKU has no magnet (-S), it cannot support legacy CS1-B/DS1-B sensors; order a sensing-equipped variant if position detection is needed. For force sizing, this 40mm bore yields 628 N push at 0.5 MPa; if less force is required, a 32mm bore provides 402 N, while a 50mm bore offers 982 N. Since the 225mm stroke exceeds 300mm, ensure adequate guidance to prevent rod bending under side loads. Note that a standard cylinder drifts without live air; for load holding, use an external pilot check valve or explore the SAIL or BSAI lock variants.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40BX225
- ✓ 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 SI40BX225 FAQ
Yes, the SI40BX225 is discontinued. The direct replacement is the SAI40BX225. It is dimensionally interchangeable per ISO 15552, retaining the same 40mm bore, 225mm stroke, 628 N force, G1/4 port, and mounting interface.
This double-acting cylinder uses a G1/4 air port. It generates 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 SAI40BX225
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40BX225 replacement — usually within 7-8 hours.