This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40X70, 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 SI40X70
The AirTAC Airtac SI40 Standard Cylinder SI40X70 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 70mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40X70, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke70 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40X70
- 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 SI40X70
The AirTAC SI40X70 is a discontinued double-acting ISO 15552 profile cylinder with a 40 mm bore and 70 mm stroke. It delivers 628 N push force at 0.5 MPa via a G1/4 port. The direct replacement is the SAI40X70, matching the exact interface, force, and mounting.
This SAI upgrade features a two Y-shaped one-way piston seal for low start-up pressure and long life. Note this specific SI40X70 SKU lacks a magnet, so it cannot accept a CS1-B or DS1-B sensor.
Airtac SI40 Standard Cylinder SI40X70 Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40X70 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40X70 |
| Bore size | Ø40 mm |
| Stroke | 70 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 SAI40X70 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 SAI40X70 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 SI40X70
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×70 | 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 SI40X70 Is Used
Compact Part Ejection
Uses the 628 N push force at 0.5 MPa to reliably push machined components out of a fixture during automated machining cycles.
Package Sorting Diverter
The 70 mm stroke actuates a diverter arm to redirect small to medium boxes on a packaging line at speeds up to 800 mm/s.
Replacing the Airtac SI40 Standard Cylinder SI40X70 with the SAI40X70
To replace the discontinued SI40X70, order the SAI40X70. Verify your ISO 15552 mounting interface (LB, FA, TC, etc.), the 70 mm stroke, and the G1/4 port. Because this non-magnet SKU cannot hold a position switch, if you need sensing you must select an SAI40X70S. For load holding, remember a standard cylinder drifts on air loss—the cushion only decelerates—so add an external pilot check valve or choose the SAIL lock variant. If sizing up or down, neighbouring bores are 32 mm (402 N push @0.5 MPa) and 50 mm (982 N push @0.5 MPa).
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40X70
- ✓ 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 SI40X70 FAQ
Yes, the SI40X70 is discontinued. The direct replacement is the AirTAC SAI40X70. It is dimensionally interchangeable per ISO 15552, retaining the same 40 mm bore, 70 mm stroke, G1/4 port, and mounting accessories.
The bore is 40 mm with a G1/4 air port and an M12x1.25 rod thread. 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.
Request a Quote for the SAI40X70
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40X70 replacement — usually within 7-8 hours.