This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40X310, 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 SI40X310
The AirTAC Airtac SI40 Standard Cylinder SI40X310 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 310mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40X310, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke310 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40X310
- 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 SI40X310
The AirTAC SI40X310 is a discontinued double-acting ISO 15552 profile cylinder with a 40mm bore and 310mm stroke. It delivers 628 N push force at 0.5 MPa via a G1/4 port. AirTAC replaced this legacy unit with the SAI40X310, a direct upgrade sharing the exact ISO 15552 mounting interface, bore, stroke and output force.
The SAI replacement features an upgraded piston seal with two Y-shaped one-way elements for low start-up pressure and long life. Note this non-magnetic SKU cannot accept a CS1-B/DS1-B sensor.
Airtac SI40 Standard Cylinder SI40X310 Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40X310 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40X310 |
| Bore size | Ø40 mm |
| Stroke | 310 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 SAI40X310 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 SAI40X310 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 SI40X310
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×310 | 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 SI40X310 Is Used
Package Diversion
Actuates routing gates on packaging lines, using the 628 N push force at 0.5 MPa to deflect cartons reliably.
Light Pressing
Provides consistent downward pressure for assembling small components, with the 310mm stroke accommodating varying part heights.
Pallet Stops
Controls pallet flow on roller conveyors, using the adjustable air cushions to decelerate the 16mm rod smoothly at stroke end.
Replacing the Airtac SI40 Standard Cylinder SI40X310 with the SAI40X310
To replace the SI40X310, order the SAI40X310. Confirm the ISO 15552 mounting interface (LB, FA, TC, etc.), the G1/4 port, and the 310mm stroke. Because this is a non-magnet SKU, it cannot support position sensing; add the -S suffix on the SAI if you need CS1-B/DS1-B switches. For sizing, the neighbouring 32mm bore yields 402 N push at 0.5 MPa, while the 50mm bore yields 982 N. A plain cylinder does not hold load on air loss—the cushion only decelerates—so use an external rod lock, pilot check valve, or the SAIL/BSAI lock variant for holding. At 310mm stroke, prevent rod bending by using external guides to manage side loads.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40X310
- ✓ 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 SI40X310 FAQ
Yes, the SI40X310 is discontinued. The direct replacement is the SAI40X310. It shares the same ISO 15552 mounting interface, 40mm bore, 310mm stroke, output force, and G1/4 port, fitting existing fixtures perfectly.
The 40mm bore uses a G1/4 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 max of 128 kgf at 1.0 MPa. The piston rod is 16mm with an M12x1.25 thread.
Request a Quote for the SAI40X310
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40X310 replacement — usually within 7-8 hours.