This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50AX850, 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 SI50 Standard Cylinder SI50AX850
The AirTAC Airtac SI50 Standard Cylinder SI50AX850 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 850mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50AX850, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke850 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50AX850
- 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 SI50 Standard Cylinder SI50AX850
The AirTAC SI50AX850 is a discontinued double-acting ISO 15552 profile cylinder with an 850 mm stroke and a 50 mm bore, delivering 982 N push force at 0.5 MPa. It features a G1/4 air port and an M16x1.5 rod thread. The direct replacement is the SAI50AX850, which maintains the exact same ISO 15552 mounting interface, output force, and port size to fit existing fixtures seamlessly.
The SAI upgrade introduces an advanced piston seal with two Y-shaped one-way elements for low start-up pressure and extended life. This specific SKU lacks a magnet (-S) and therefore cannot accept position sensors. The default carbon steel rod can be swapped for the SUS420J2 stainless option, and a Viton H seal raises the temperature limit to 150 C.
Airtac SI50 Standard Cylinder SI50AX850 Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50AX850 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50AX850 |
| Bore size | Ø50 mm |
| Stroke | 850 mm |
| Acting type | Double acting |
| Port size | G1/4 |
| Rod thread | M16×1.5 |
| 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, 30 mm |
| Max standard stroke | Up to 1200 mm |
Specifications follow the official AirTAC SI datasheet (now discontinued). The SAI50AX850 carries the same ISO 15552 ratings. Confirm against the product label before installation. Thread options: PT / G / NPT.
Theoretical Output Force (Ø50mm)
| Pressure | Push force | Pull force |
|---|---|---|
| 0.5 MPa | 982 N | 825 N |
| 0.7 MPa | 1374 N | — |
| Max (@1.0 MPa) | 200 kgf | |
The SAI50AX850 produces the same force from the same bore. Actual usable force is lower than theoretical; size with a margin.
Model Code: Airtac SI50 Standard Cylinder SI50AX850
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×850 | 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 SI50 Standard Cylinder SI50AX850 Is Used
Long-Stroke Diversion
Pushes packages across transfer lines using the full 850 mm extension, relying on external guides to prevent rod bending.
Ejector Mechanism
Ejects machined parts from fixtures using 982 N of thrust, with adjustable cushions decelerating the 20 mm rod.
Replacing the Airtac SI50 Standard Cylinder SI50AX850 with the SAI50AX850
To replace the discontinued SI50AX850, order the SAI50AX850. Verify your ISO 15552 mounting accessory (LB, FA, TC, etc.), the G1/4 port, and the M16x1.5 rod thread. Because this SKU has no magnet, it cannot support legacy CS1-B/DS1-B switches; if sensing is required, select an SAI50X850S model. Sizing checks: the 50 mm bore yields 982 N push at 0.5 MPa, while the neighboring 63 mm bore offers 1559 N. Note that a plain cylinder drifts on air loss; for load holding, use an external pilot check valve or explore the SAIL lock or BSAI clamp-lock variants. Finally, the 850 mm stroke demands external guides to prevent rod bending and manage side loads.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50AX850
- ✓ Same bore / stroke / force
- ✓ Port/thread type (PT/G/NPT)
- ✓ Magnet (-S) for sensors?
- ✓ Mounting reused (FA/FB/CA/CB/CR/LB/TC)
Airtac SI50 Standard Cylinder SI50AX850 FAQ
Yes, the SI50AX850 is discontinued. The direct replacement is the SAI50AX850. It shares the identical ISO 15552 mounting interface, 50 mm bore, 850 mm stroke, force, and G1/4 port, fitting existing setups perfectly while upgrading the piston seal.
The G1/4 port bore delivers a push force of 982 N and a pull force of 825 N at 0.5 MPa. At 0.7 MPa it pushes 1374 N, and the theoretical maximum force is 200 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50AX850
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50AX850 replacement — usually within 7-8 hours.