This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X1250N, 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 SI125X1250N
The AirTAC SI125 Standard Cylinder SI125X1250N is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 1250mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125X1250N, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke1250 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125X1250N
- 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 SI125X1250N
The AirTAC SI125X1250N is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore and 1250 mm stroke. Delivering 6136 N push at 0.5 MPa via a G1/2 port, it is superseded by the SAI125X1250N direct replacement. This upgrade retains the exact ISO 15552 mounting interface, bore, and force, but introduces an upgraded piston seal with two Y-shaped one-way elements for lower start-up pressure and longer life. The NBR seal supports -20 to +70 C, with a Viton H option for high heat.
Because this SKU lacks the -S magnet, it cannot accept position sensors (legacy CS1-B/DS1-B). Note that the SAI family adds lock variants (SAIL, BSAI) absent in the SI line for secure load holding.
Airtac SI125 Standard Cylinder SI125X1250N Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X1250N |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X1250N |
| Bore size | Ø125 mm |
| Stroke | 1250 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 SAI125X1250N 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 SAI125X1250N 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 SI125X1250N
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×1250 | 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 SI125X1250N Is Used
Heavy Material Transfer
Drives large pallets or heavy assemblies over 1250 mm distances on production lines, utilizing the 6136 N push force at 0.5 MPa to move substantial loads reliably.
Large Press Feeding
Feeds heavy sheet metal or structural components into large industrial presses, taking advantage of the 125 mm bore's 8590 N output at 0.7 MPa for consistent positioning.
Replacing the Airtac SI125 Standard Cylinder SI125X1250N with the SAI125X1250N
To replace the discontinued SI125X1250N, order the SAI125X1250N. Verify your ISO 15552 mounting fixtures, bore, 1250 mm stroke, G1/2 port, and M27x2 rod thread. Since this is a non-magnet SKU, it cannot support switches; add the -S suffix on the SAI if you need CS1-B/DS1-B sensing. When sizing, neighbouring bores offer different forces: the 100 mm bore provides 3927 N push, while the 160 mm bore yields 10053 N at 0.5 MPa. For a 1250 mm stroke, external guides are strongly recommended to prevent rod bending and side-load damage. A plain cylinder drifts on air loss; for load holding, use the SAIL or BSAI lock variant, or an external pilot check valve.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X1250N
- ✓ 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 SI125X1250N FAQ
Yes, the SI125X1250N is discontinued. The direct replacement is the SAI125X1250N. It features the same ISO 15552 mounting interface, 125 mm bore, 1250 mm stroke, output force, and G1/2 port, fitting existing fixtures perfectly while upgrading the piston seal.
The G1/2 port feeds a 32 mm rod delivering 6136 N push and 5734 N pull at 0.5 MPa. At 0.7 MPa push is 8590 N, and 11045 N at 0.9 MPa. The theoretical max is 1251 kgf at 1.0 MPa. Operating speed is 30-500 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125X1250N
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125X1250N replacement — usually within 7-8 hours.