This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50X125H, 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 SI50X125H
The AirTAC SI50 Standard Cylinder SI50X125H 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 SAI50X125H, 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 → SAI50X125H
- 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 SI50X125H
The AirTAC SI50X125H is a discontinued double-acting ISO 15552 profile cylinder with a 50mm bore and 125mm stroke. Delivering 982N push force at 0.5MPa via a G1/4 port, its direct successor is the SAI50X125H. This replacement shares the identical mounting interface, bore, stroke and output force, fitting existing fixtures perfectly.
The SAI upgrade features a two Y-shaped one-way piston seal for low start-up pressure and long life. This SKU lacks a magnet and cannot take a sensor, but the -H seal specifies Viton FKM for 0-150C high-temp environments.
Airtac SI50 Standard Cylinder SI50X125H Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50X125H |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50X125H |
| 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 SAI50X125H 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 SAI50X125H 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 SI50X125H
| 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 SI50X125H Is Used
Hot Stamp Presses
Handles 125mm actuation in heated tooling zones, leveraging the Viton H seal to withstand 0-150C ambient temperatures without degrading.
High-Temp Diverters
Pushes mid-weight products along lines safely, providing a 589N working load margin for consistent 50kg payload routing operations.
Oven Door Lifting
Raises and lowers insulated industrial oven doors using the 982N push force at 0.5MPa, relying on external check valves for secure holding.
Replacing the Airtac SI50 Standard Cylinder SI50X125H with the SAI50X125H
To replace the SI50X125H, order the SAI50X125H keeping the identical ISO 15552 interface, 125mm stroke, G1/4 port and mounting accessories. If sizing up or down, neighboring bores are 40mm (628N push @0.5MPa) and 63mm (1559N push @0.5MPa). This non-magnet SKU cannot accept a CS1-B/DS1-B sensor. A plain cylinder drifts on air loss—the cushion only decelerates—so use an external pilot check valve or the SAIL/BSAI lock variant for held loads. The SAI family also adds the SAIF self-valve option.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50X125H
- ✓ 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 SI50X125H FAQ
Yes, the SI50X125H is discontinued. The direct replacement is the SAI50X125H. It is dimensionally interchangeable per ISO 15552, matching the 50mm bore, 125mm stroke, G1/4 port and mounting interface.
The 50mm bore uses a G1/4 port, M16x1.5 rod thread and 30mm cushion. It generates 982N push and 825N pull at 0.5MPa, 1374N push at 0.7MPa, 1767N at 0.9MPa, and a 200kgf max at 1.0MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50X125H
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50X125H replacement — usually within 7-8 hours.