This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X650, 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 SI125 Standard Cylinder SI125X650
The AirTAC SI125 Standard Cylinder SI125X650 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 650mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125X650, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke650 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125X650
- 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 SI125 Standard Cylinder SI125X650
The AirTAC SI125X650 is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore and 650 mm stroke. It delivers 6136 N push force at 0.5 MPa through a G1/2 port. AirTAC replaced this legacy unit with the SAI125X650, a direct upgrade retaining the exact ISO 15552 mounting interface, M27x2 rod thread, and 40 mm cushions.
The SAI upgrade features a new piston seal with two Y-shaped one-way elements for low start-up pressure and long life. Note this SKU lacks a magnet (-S) and cannot accept CS1-B/DS1-B sensors.
Airtac SI125 Standard Cylinder SI125X650 Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X650 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X650 |
| Bore size | Ø125 mm |
| Stroke | 650 mm |
| Acting type | Double acting |
| Port size | G1/2 |
| Rod thread | M27×2.0 |
| 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 – 500 mm/s |
| Cushion | Adjustable, 40 mm |
| Max standard stroke | Up to 1500 mm |
Specifications follow the official AirTAC SI datasheet (now discontinued). The SAI125X650 carries the same ISO 15552 ratings. Confirm against the product label before installation. Thread options: PT / G / NPT.
Theoretical Output Force (Ø125mm)
| Pressure | Push force | Pull force |
|---|---|---|
| 0.5 MPa | 6136 N | 5734 N |
| 0.7 MPa | 8590 N | — |
| Max (@1.0 MPa) | 1251 kgf | |
The SAI125X650 produces the same force from the same bore. Actual usable force is lower than theoretical; size with a margin.
Model Code: Airtac SI125 Standard Cylinder SI125X650
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×650 | 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 SI125 Standard Cylinder SI125X650 Is Used
Heavy Stamping
Drives large press beds and heavy-duty stamping fixtures requiring 6136 N of thrust at 0.5 MPa.
Pallet Handling
Indexes loaded pallets along transfer lines, utilizing the 650 mm stroke for wide material indexing.
Automated Assembly
Actuates substantial welding guns or clamping gantries where a robust 125 mm profile barrel is necessary.
Replacing the Airtac SI125 Standard Cylinder SI125X650 with the SAI125X650
To replace the SI125X650, order the SAI125X650. Confirm the ISO 15552 interface, 650 mm stroke, G1/2 port (PT/G/NPT), and mounting accessory (LB, FA, TC, etc.). Because this non-magnet SKU lacks a piston magnet, it cannot support position sensing; if switches are needed, specify an SAI125X650S. Sizing both ways: a 100 mm bore yields 3927 N push at 0.5 MPa, while a 160 mm bore yields 10053 N. For the 650 mm stroke, use external guides to prevent rod bending and side-load damage. The air cushion only decelerates; it does not hold load. For static holding on air loss, use an external rod lock, pilot check valve, or the SAIL/BSAI lock variant.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X650
- ✓ Same bore / stroke / force
- ✓ Port/thread type (PT/G/NPT)
- ✓ Magnet (-S) for sensors?
- ✓ Mounting reused (FA/FB/CA/CB/CR/LB/TC)
Airtac SI125 Standard Cylinder SI125X650 FAQ
Yes, the AirTAC SI125X650 is discontinued. The direct replacement is the SAI125X650. It is dimensionally interchangeable per ISO 15552, retaining the same 125 mm bore, 650 mm stroke, output force, G1/2 port, and mounting accessories.
The G1/2 port feeds a 32 mm rod. At 0.5 MPa it pushes 6136 N and pulls 5734 N. At 0.7 MPa push is 8590 N, and at 0.9 MPa it is 11045 N. The theoretical max force is 1251 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125X650
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125X650 replacement — usually within 7-8 hours.