This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50AX325, 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 SI50AX325
The AirTAC Airtac SI50 Standard Cylinder SI50AX325 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 325mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50AX325, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke325 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50AX325
- 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 SI50AX325
The AirTAC SI50AX325 is a discontinued double-acting ISO 15552 profile cylinder with a 50 mm bore and 325 mm stroke, delivering 982 N push force at 0.5 MPa. The direct replacement is the SAI50AX325, which shares the exact same G1/4 port, M16x1.5 rod thread, and mounting interface. This specific SKU features a SUS420J2 stainless steel rod for corrosion resistance but lacks a magnet, meaning it cannot accept position sensors.
Upgrading to the SAI retains the original ratings but introduces an upgraded piston seal with two Y-shaped elements for low start-up pressure and extended life. Note that a plain cylinder drifts without live air; use an external rod lock or the SAIL lock variant for secure holding.
Airtac SI50 Standard Cylinder SI50AX325 Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50AX325 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50AX325 |
| Bore size | Ø50 mm |
| Stroke | 325 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 SAI50AX325 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 SAI50AX325 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 SI50AX325
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×325 | 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 SI50AX325 Is Used
Diverting Gates
Actuates routing flaps on packaging lines, utilizing the 982 N thrust to push heavy cardboard cartons reliably at speeds up to 800 mm/s.
Vertical Pressing
Applies downward clamping pressure for light assembly tasks, safely handling loads up to 50 kg with the SUS420J2 stainless rod resisting moisture.
Pallet Stops
Extends 325 mm to halt pallets on roller conveyors, requiring external guide rails to absorb side-load impacts during deceleration.
Replacing the Airtac SI50 Standard Cylinder SI50AX325 with the SAI50AX325
To replace the discontinued SI50AX325, order the SAI50AX325, confirming the ISO 15552 mounting interface, 50 mm bore, 325 mm stroke, and G1/4 port. Because this SKU lacks the -S magnet, it cannot support legacy CS1-B/DS1-B sensors; if sensing is required, select an SAI equivalent with a magnet. When sizing, a 40 mm bore provides 628 N push at 0.5 MPa, while a 63 mm bore offers 1559 N. At 325 mm, this long stroke requires external guides to prevent rod bending and side-load damage. For load holding on air loss, add a pilot-operated check valve or explore the SAIL or BSAI lock variants, as the standard cushion only decelerates.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50AX325
- ✓ 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 SI50AX325 FAQ
Yes, the SI50AX325 is discontinued. The direct replacement is the SAI50AX325. It is dimensionally interchangeable per ISO 15552, maintaining the same 50 mm bore, 325 mm stroke, 982 N output force, G1/4 port, and mounting fixtures.
This double-acting cylinder features a G1/4 air port and generates 982 N push and 825 N pull at 0.5 MPa. At 0.7 MPa it pushes 1374 N, and 1767 N at 0.9 MPa. The theoretical maximum force is 200 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50AX325
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50AX325 replacement — usually within 7-8 hours.