This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125BX100, 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 SI125BX100
The AirTAC SI125 Standard Cylinder SI125BX100 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 100mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125BX100, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke100 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125BX100
- 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 SI125BX100
The AirTAC SI125BX100 is a discontinued double-acting ISO 15552 profile cylinder with a 125mm bore and 100mm stroke. Delivering 6136N push force at 0.5MPa via a G1/2 port, it is replaced by the SAI125BX100. This direct upgrade matches the exact ISO 15552 mounting interface, bore, stroke, output force, and accessories. The SAI features an upgraded piston seal with two Y-shaped one-way elements for low start-up pressure and long life. This SI125BX100 variant uses a SUS304 stainless piston rod for corrosion resistance, but lacks a magnet (-S), meaning it cannot accept position sensors.
The SAI family also introduces lock and valve variants the SI lacked, such as SAIL and BSAI clamp-locks. Note that a plain cylinder does not hold load on air loss; the cushion only decelerates.
Airtac SI125 Standard Cylinder SI125BX100 Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125BX100 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125BX100 |
| Bore size | Ø125 mm |
| Stroke | 100 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 SAI125BX100 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 SAI125BX100 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 SI125BX100
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×100 | 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 SI125BX100 Is Used
Heavy Stamping Press
Drives large press dies requiring high thrust, utilizing the 6136N push force at 0.5MPa to form thick metal components reliably.
Pallet Lift Gate
Actuates robust lifting gates for heavy logistics pallets, where the SUS304 stainless rod provides necessary corrosion resistance.
Injection Mold Clamp
Secures heavy industrial molds using the 125mm bore's 1251kgf maximum theoretical force, ensuring rigid holding during manufacturing.
Replacing the Airtac SI125 Standard Cylinder SI125BX100 with the SAI125BX100
To replace the discontinued SI125BX100, order the SAI125BX100. Confirm the ISO 15552 mounting interface, the 125mm bore, 100mm stroke, and G1/2 port. Retain your original mounting accessory (LB, FA, TC, etc.) and note this -B variant uses a SUS304 stainless rod. Because this SKU lacks a magnet, it cannot take legacy CS1-B/DS1-B sensors; order an -S version if sensing is needed. Sizing both ways: the 100mm bore offers 3927N push at 0.5MPa, while the 160mm bore offers 10053N. For load holding on air loss, the cushion only decelerates; use an external rod lock, pilot check valve, or the SAIL/BSAI lock variant. The 30-500mm/s speed range suits heavy cycles.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125BX100
- ✓ 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 SI125BX100 FAQ
Yes, the AirTAC SI125BX100 is discontinued. The direct replacement is the SAI125BX100. It is a true ISO 15552 profile cylinder that matches the original bore, stroke, force, G1/2 port, and mounting interface, dropping directly into existing fixtures.
The 125mm bore features a G1/2 air port. It delivers 6136N push and 5734N pull at 0.5MPa, 8590N push at 0.7MPa, 11045N push at 0.9MPa, and a theoretical max force of 1251kgf at 1.0MPa. The piston rod is 32mm with an M27x2 thread.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125BX100
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125BX100 replacement — usually within 7-8 hours.