This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50X126S, 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 SI50X126S
The AirTAC Airtac SI50 Standard Cylinder SI50X126S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 126mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50X126S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke126 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50X126S
- 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 SI50X126S
The AirTAC SI50X126S is a discontinued double-acting ISO 15552 profile cylinder with a 50 mm bore, 126 mm stroke, and a built-in piston magnet for CS1-B/DS1-B switches. It delivers 982 N push force at 0.5 MPa. AirTAC replaced this legacy unit with the SAI50X126S, a direct upgrade sharing the exact ISO 15552 mounting interface, G1/4 port, and accessories.
The SAI replacement features an upgraded piston seal with two Y-shaped one-way elements for lower start-up pressure and longer life. The SAI family also adds SAIL, SAIF, and BSAI lock variants the SI lacked.
Airtac SI50 Standard Cylinder SI50X126S Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50X126S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50X126S |
| Bore size | Ø50 mm |
| Stroke | 126 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 SAI50X126S 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 SAI50X126S 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 SI50X126S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×126 | 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 SI50X126S Is Used
Package Diverting
Pushes medium-weight cartons off a main conveyor line using the 982 N push force at 0.5 MPa.
Clamp Actuation
Secures workpieces in machining fixtures where the 50 mm bore provides ample holding without bulk.
Vertical Lifting
Elevates goods up to 50 kg in pick-and-place units, relying on the magnet for position feedback.
Replacing the Airtac SI50 Standard Cylinder SI50X126S with the SAI50X126S
To replace the discontinued SI50X126S, order the SAI50X126S keeping the 50 mm bore, 126 mm nonstandard stroke, G1/4 port, M16x1.5 rod thread, and -S magnet. Because 126 mm is a nonstandard stroke, confirm availability. The SAI is dimensionally interchangeable per ISO 15552. If you need more force, the neighboring 63 mm bore yields 1559 N push at 0.5 MPa; if less is required, the 40 mm bore gives 628 N. Note that a plain cylinder drifts on air loss as the cushion only decelerates; for load holding, use an external rod lock, pilot check valve, or the SAIL/BSAI lock variant.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50X126S
- ✓ 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 SI50X126S FAQ
Yes, the SI50X126S is discontinued. The direct replacement is the SAI50X126S. It shares the same ISO 15552 mounting interface, 50 mm bore, 126 mm stroke, G1/4 port, and output force, fitting existing fixtures perfectly.
The 50 mm bore uses a G1/4 port. Force output is 982 N push and 825 N pull at 0.5 MPa, 1374 N push at 0.7 MPa, and a theoretical max of 200 kgf at 1.0 MPa. It operates at 30-800 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50X126S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50X126S replacement — usually within 7-8 hours.