This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125BX65S, 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 SI125BX65S
The AirTAC SI125 Standard Cylinder SI125BX65S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 65mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125BX65S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke65 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125BX65S
- 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 SI125BX65S
The AirTAC SI125BX65S is a discontinued double-acting ISO 15552 profile cylinder with a 125mm bore and 65mm stroke. It delivers 6136N push force at 0.5MPa via a G1/2 port. The direct replacement is the SAI125BX65S, sharing the exact ISO 15552 mounting interface, force, and dimensions. This specific unit features a SUS304 stainless piston rod (-B) and a piston magnet (-S) for legacy CS1-B/DS1-B sensors.
Upgrading to the SAI125BX65S introduces an improved piston seal with two Y-shaped one-way elements for low start-up pressure. The SAI family also adds SAIL, SAIF, and BSAI lock variants absent in the SI line.
Airtac SI125 Standard Cylinder SI125BX65S Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125BX65S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125BX65S |
| Bore size | Ø125 mm |
| Stroke | 65 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 SAI125BX65S 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 SAI125BX65S 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 SI125BX65S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×65 | 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 SI125BX65S Is Used
Heavy Press Clamping
Ideal for securing heavy metal components during machining, utilizing the 6136N push force and SUS304 rod for corrosion resistance in coolant environments.
Automated Assembly Actuation
Drives robust linear motion in large-scale automated lines, where the ISO 15552 interface allows direct swapping into existing fixture mounts.
Replacing the Airtac SI125 Standard Cylinder SI125BX65S with the SAI125BX65S
To replace the SI125BX65S, order the SAI125X65BS equivalent, confirming the ISO 15552 mounting accessory, G1/2 port, and SUS304 rod. If you need to size up or down, neighboring bores are 100mm and 160mm; at 0.5MPa this 125mm bore provides 6136N push and 5734N pull. Because this is a plain cylinder, it cannot hold a load without live air—the 40mm adjustable cushions only decelerate. For load-holding, use an external pilot check valve or the SAIL/BSAI lock variant. The standard speed range is 30-500mm/s.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125BX65S
- ✓ 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 SI125BX65S FAQ
Yes, the AirTAC SI125BX65S is discontinued. The direct replacement is the SAI125BX65S. It is dimensionally interchangeable per ISO 15552, retaining the same 125mm bore, 65mm stroke, G1/2 port, and mounting interface.
At 0.5MPa it provides 6136N push and 5734N pull. At 0.7MPa push is 8590N, and at 0.9MPa it is 11045N. The theoretical max force is 1251kgf at 1.0MPa. It has a 32mm rod, M27x2 thread, 40mm cushion, and operates at 30-500mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125BX65S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125BX65S replacement — usually within 7-8 hours.