This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50X125CA, 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 SI50X125CA
The AirTAC Airtac SI50 Standard Cylinder SI50X125CA is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 125mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50X125CA, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke125 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50X125CA
- 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 SI50X125CA
The AirTAC SI50X125CA is a discontinued double-acting ISO 15552 profile cylinder with a 50mm bore and 125mm stroke. It delivers 982N push and 825N pull at 0.5MPa through a G1/4 port. AirTAC replaced this legacy unit with the SAI50X125CA, a direct upgrade retaining the exact CA clevis mounting interface, output force, and dimensions.
The SAI replacement features an upgraded piston seal with two Y-shaped one-way elements for low start-up pressure and extended life. Because this specific SI SKU lacks the -S magnet suffix, it cannot accept position switches like the legacy CS1-B/DS1-B sensors.
Airtac SI50 Standard Cylinder SI50X125CA Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50X125CA |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50X125CA |
| Bore size | Ø50 mm |
| Stroke | 125 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 SAI50X125CA 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 SAI50X125CA 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 SI50X125CA
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×125 | 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 SI50X125CA Is Used
Clamp Actuation
Provides 982N of clamping force at 0.5MPa for securing mid-weight workpieces during machining or welding operations.
Package Diverting
Drives a 125mm stroke diverter arm to route medium-sized cartons on packaging lines with reliable double-acting motion.
Replacing the Airtac SI50 Standard Cylinder SI50X125CA with the SAI50X125CA
To replace the discontinued SI50X125CA, order the SAI50X125CA. Verify your ISO 15552 interface, 50mm bore, 125mm stroke, G1/4 port thread (PT/G/NPT), and the CA clevis mounting accessory. Since this SKU has no -S magnet, it cannot support sensors; if position detection is needed, select an SAI50X125CAS equivalent. Sizing alternatives: step down to a 40mm bore (628N push @0.5MPa) for lighter loads, or up to a 63mm bore (1559N push @0.5MPa) for higher force. Note that a plain cylinder drifts on air loss—the cushion only decelerates near stroke end—so for load holding consider an external pilot check valve or the SAIL/BSAI lock variants. The SAI family also adds the SAIF self-valve option (bores 32-100) the SI lacked.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50X125CA
- ✓ 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 SI50X125CA FAQ
Yes, the SI50X125CA is discontinued. The direct replacement is the AirTAC SAI50X125CA. It matches the ISO 15552 mounting dimensions, 50mm bore, 125mm stroke, G1/4 port, and CA clevis interface, dropping directly into existing fixtures.
The 50mm bore features a G1/4 air port and M16x1.5 rod thread. It delivers 982N push and 825N pull at 0.5MPa, 1374N push at 0.7MPa, 1767N push at 0.9MPa, and a theoretical maximum of 200kgf at 1.0MPa. Operating speed is 30-800mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50X125CA
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50X125CA replacement — usually within 7-8 hours.