This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X40, 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 SI125X40
The AirTAC SI125 Standard Cylinder SI125X40 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 40mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125X40, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke40 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125X40
- 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 SI125X40
The AirTAC SI125X40 is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore and 40 mm stroke. It delivers 6136 N push and 5734 pull at 0.5 MPa via a G1/2 port. AirTAC replaced it with the SAI125X40 direct.
The SAI125X40 matches the exact ISO 15552 mounting interface, force, and port. It upgrades the piston seal to two Y-shaped elements for low start-up pressure. This SKU lacks a magnet, so it cannot take a sensor.
Airtac SI125 Standard Cylinder SI125X40 Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X40 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X40 |
| Bore size | Ø125 mm |
| Stroke | 40 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 SAI125X40 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 SAI125X40 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 SI125X40
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×40 | 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 SI125X40 Is Used
Heavy Pressing
Drives large stamping and pressing fixtures requiring substantial thrust, utilizing the 6136 N push force at 0.5 MPa.
Clamp Actuation
Secures heavy industrial workpieces in automated machining lines where a robust 125 mm bore and short 40 mm stroke are ideal.
Replacing the Airtac SI125 Standard Cylinder SI125X40 with the SAI125X40
To replace the SI125X40, order the SAI125X40. Verify your ISO 15552 mounting accessory (LB, FA, TC), the G1/2 port thread (PT, G, or NPT), and the M27x2 rod end. Since this specific SKU has no -S magnet, it cannot support CS1-B/DS1-B sensors; order a magnet-equipped SAI if position feedback is required. For sizing, the 125 mm bore yields 6136 N push at 0.5 MPa (8590 N at 0.7 MPa), while the neighboring 100 mm bore provides 3927 N. Note that a plain cylinder drifts on air loss; for load holding, use an external pilot check valve or the SAIL/BSAI lock variants. The 40 mm stroke is well within the 1500 mm standard limit, so side-load rod bending is minimal.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X40
- ✓ 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 SI125X40 FAQ
Yes, the AirTAC SI125X40 is discontinued. The direct replacement is the SAI125X40. It features the same ISO 15552 mounting interface, 125 mm bore, 40 mm stroke, output force, and G1/2 port, fitting directly into existing fixtures.
This double-acting cylinder uses a G1/2 air port. It generates 6136 N push and 5734 N pull at 0.5 MPa, 8590 N push at 0.7 MPa, 11045 N push at 0.9 MPa, and a theoretical maximum of 1251 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125X40
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125X40 replacement — usually within 7-8 hours.