This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X155SN, 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 SI125X155SN
The AirTAC SI125 Standard Cylinder SI125X155SN is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 155mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125X155SN, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke155 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125X155SN
- 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 SI125X155SN
The AirTAC SI125X155SN is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore and 155 mm stroke. Delivering 6136 N push force at 0.5 MPa, it features a G1/2 port, M27x2 rod thread, and adjustable air cushions. The direct replacement is the SAI125X155SN, matching the bore, stroke, force, port, and ISO 15552 mounting interface for existing fixtures.
The SAI upgrade introduces a two Y-shaped one-way piston seal for low start-up pressure and long life. The NBR seal handles -20 to +70 C, while Viton H extends this to 150 C. The -S magnet pairs with legacy CS1-B/DS1-B sensors, and rod materials include carbon steel, SUS420J2, or SUS304.
Airtac SI125 Standard Cylinder SI125X155SN Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X155SN |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X155SN |
| Bore size | Ø125 mm |
| Stroke | 155 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 SAI125X155SN 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 SAI125X155SN 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 SI125X155SN
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×155 | 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 SI125X155SN Is Used
Heavy Stamping Press
Drives heavy stamping dies requiring 6136 N push at 0.5 MPa, utilizing the 155 mm stroke to form thick metal components securely.
Injection Mold Clamp
Holds large injection molding halves in place, relying on the G1/2 port and 30-500 mm/s speed for stable heavy-duty operation.
Replacing the Airtac SI125 Standard Cylinder SI125X155SN with the SAI125X155SN
To replace the SI125X155SN, order the SAI125X155SN. Verify the ISO 15552 mounting interface (LB, FA, TC, etc.), the G1/2 port, the 155 mm stroke, and the -S magnet for CS1-B/DS1-B switches. Operating speed is 30-500 mm/s. For sizing, neighbouring bores are 100 mm (3927 N [email protected]) and 160 mm (10053 N); this 125 mm bore yields 6136 N push and 5734 N pull at 0.5 MPa, with a 1251 kgf max at 1.0 MPa. Note that a plain cylinder drifts on air loss; the cushion only decelerates. For load holding, use an external rod lock, pilot check valve, or the SAIL/BSAI lock variants. The SAIF self-valve is unavailable for 125 mm bores.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X155SN
- ✓ 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 SI125X155SN FAQ
Yes, the AirTAC SI125X155SN is discontinued. The direct replacement is the SAI125X155SN. It is dimensionally interchangeable per ISO 15552, matching the 125 mm bore, 155 mm stroke, 6136 N force, G1/2 port, and mounting accessories.
The bore is 125 mm with a G1/2 air port. 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 SAI125X155SN
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125X155SN replacement — usually within 7-8 hours.