This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X375, 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 SI125X375
The AirTAC SI125 Standard Cylinder SI125X375 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 375mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125X375, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke375 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125X375
- 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 SI125X375
The AirTAC SI125X375 is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore and 375 mm stroke. It delivers 6136 N push force at 0.5 MPa via a G1/2 port. The direct replacement is the SAI125X375, matching the bore, stroke, force, port and ISO 15552 mounting interface for existing fixtures.
The SAI upgrade features a two Y-shaped one-way piston seal for low start-up pressure and long life. This non-magnet SKU cannot take a sensor. For high heat, Viton H seals raise the temperature range to 0-150 C.
Airtac SI125 Standard Cylinder SI125X375 Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X375 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X375 |
| Bore size | Ø125 mm |
| Stroke | 375 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 SAI125X375 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 SAI125X375 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 SI125X375
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×375 | 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 SI125X375 Is Used
Heavy Press Forming
Provides the 6136 N push at 0.5 MPa required for stamping and forming dense metal or composite panels in automated press lines.
Large Mold Ejection
Ejects heavy industrial molds from casting machinery, utilizing the 125 mm bore and adjustable 40 mm air cushions to decelerate at stroke end.
Replacing the Airtac SI125 Standard Cylinder SI125X375 with the SAI125X375
To replace the SI125X375, order the SAI125X375 and confirm the ISO 15552 mounting interface, G1/2 port, M27x2 rod thread and 40 mm cushions. This non-S SKU lacks a magnet and cannot accept CS1-B/DS1-B sensors. For sizing both ways: a 100 mm bore gives 3927 N push at 0.5 MPa, while a 160 mm bore gives 10053 N. Note that a plain cylinder drifts on air loss—the cushion only decelerates; use the SAIL or BSAI lock variant for load holding. Finally, at 375 mm stroke, use external guides to prevent rod bending and side-load wear.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X375
- ✓ 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 SI125X375 FAQ
Yes, the AirTAC SI125X375 is discontinued and end-of-life. The direct replacement is the SAI125X375. It is dimensionally interchangeable per the ISO 15552 mounting interface, retaining the same 125 mm bore, 375 mm stroke, output force, G1/2 port and mounting accessories.
This double-acting cylinder uses a G1/2 air port. The force ratings are: 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 max of 1251 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125X375
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125X375 replacement — usually within 7-8 hours.