This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125BX165S, 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 SI125BX165S
The AirTAC SI125 Standard Cylinder SI125BX165S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 165mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125BX165S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke165 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125BX165S
- 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 SI125BX165S
The AirTAC SI125BX165S is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore and 165 mm stroke. It delivers 6136 N push and 5734 N pull at 0.5 MPa, operating via a G1/2 port. This unit features a SUS304 stainless steel rod and a built-in piston magnet for legacy CS1-B/DS1-B sensors. AirTAC replaced it with the SAI125BX165S, a direct upgrade retaining the exact ISO 15552 mounting interface, force, and stroke.
The SAI replacement incorporates an upgraded piston seal utilizing two Y-shaped one-way elements for low start-up pressure and extended life. The SAI family also introduces SAIL and BSAI lock variants absent in the legacy line, while a Viton H seal option expands the temperature range to 0-150 C.
Airtac SI125 Standard Cylinder SI125BX165S Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125BX165S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125BX165S |
| Bore size | Ø125 mm |
| Stroke | 165 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 SAI125BX165S 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 SAI125BX165S 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 SI125BX165S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×165 | 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 SI125BX165S Is Used
Heavy Stamping Press
Drives large heavy-duty stamping dies requiring 6136 N of push force at 0.5 MPa with robust SUS304 stainless rod resistance to shop-floor coolant.
Woodworking Clamp
Secures large timber beams during automated cutting operations, relying on the rigid ISO 15552 profile barrel to withstand significant side loads.
Replacing the Airtac SI125 Standard Cylinder SI125BX165S with the SAI125BX165S
To replace the SI125BX165S, order the SAI125BX125S keeping the exact 125 mm bore, 165 mm stroke, G1/2 port, and ISO 15552 mounting interface. Confirm your thread standard (PT/G/NPT) and mounting accessory (LB, FA, TC, etc.). The -S magnet supports legacy CS1-B/DS1-B sensors, though the SAI uses current AirTAC switches. The -B rod is SUS304 stainless steel, ideal for corrosive environments compared to the standard carbon steel. For sizing, neighbouring bores are 100 mm (3927 N push @0.5 MPa) and 160 mm (10053 N push). Note that a plain cylinder drifts without live air; the cushion only decelerates. For load holding, use an external pilot check valve or the SAIL/BSAI lock variant.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125BX165S
- ✓ 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 SI125BX165S FAQ
Yes, the SI125BX165S is discontinued. The direct replacement is the SAI125BX165S. It shares the identical ISO 15552 mounting interface, 125 mm bore, 165 mm stroke, G1/2 port, and output force, fitting existing fixtures perfectly while adding an upgraded piston seal.
It features 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 maximum of 1251 kgf at 1.0 MPa. It operates at 30-500 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125BX165S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125BX165S replacement — usually within 7-8 hours.