This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI40X156, 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 SI40X156
The AirTAC SI40 Standard Cylinder SI40X156 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 156mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI40X156, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke156 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → SAI40X156
- 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 SI40X156
The AirTAC SI40X156 is a discontinued double-acting ISO 15552 profile cylinder with a 40mm bore and 156mm stroke. It delivers 628N push force at 0.5MPa through a G1/4 port. AirTAC replaced this legacy unit with the SAI40X156, a direct sharing the exact interface, bore, stroke and mounts.
The SAI upgrade features a two Y-shaped one-way piston seal for low start-up pressure and long life. This non-magnet SKU cannot take a sensor. For high heat, Viton H seals raise limits to 150C.
Airtac SI40 Standard Cylinder SI40X156 Technical Specifications
| Model | Airtac SI40 Standard Cylinder SI40X156 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI40X156 |
| Bore size | Ø40 mm |
| Stroke | 156 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 SAI40X156 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 SAI40X156 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 SI40X156
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×156 | 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 SI40X156 Is Used
Clamp Actuation
Provides 628N of clamping force at 0.5MPa for securing mid-weight workpieces during machining operations.
Package Diversion
Drives a 156mm stroke diverter arm to route small to medium packages on material handling lines.
Replacing the Airtac SI40 Standard Cylinder SI40X156 with the SAI40X156
To replace the SI40X156, order the SAI40X156 direct, confirming the ISO 15552 interface, 40mm bore, 156mm stroke, G1/4 port and mounting accessory. This 156mm stroke is non-standard (max standard is 1200mm), so verify machining. Since stroke exceeds 100mm, use a guide to prevent rod bending under side loads. Size both ways: the 32mm bore yields 402N push @0.5MPa, while the 50mm bore yields 982N. A plain cylinder drifts on air loss—the cushion only decelerates—so for load holding use an external pilot check valve or the SAIL lock variant. This no-S model lacks a magnet and cannot accept CS1-B/DS1-B switches.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI40X156
- ✓ 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 SI40X156 FAQ
Yes, the AirTAC SI40X156 is discontinued. The direct replacement is the SAI40X156. It shares the identical ISO 15552 mounting interface, 40mm bore, 156mm stroke, output force, G1/4 port and accessories, fitting existing fixtures perfectly.
The 40mm bore double-acting cylinder operates at 30-800mm/s. It generates 628N push and 528N pull at 0.5MPa, 879N push at 0.7MPa, 1130N push at 0.9MPa, and a theoretical max of 128kgf at 1.0MPa. It uses a G1/4 air port and M12x1.25 rod thread.
Request a Quote for the SAI40X156
Send us the quantity and destination. We confirm price, stock and lead time on the SAI40X156 replacement — usually within 7-8 hours.