This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125BX500FA, 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 SI125BX500FA
The AirTAC SI125 Standard Cylinder SI125BX500FA is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 500mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125BX500FA, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke500 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125BX500FA
- 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 SI125BX500FA
The AirTAC SI125BX500FA is a discontinued double-acting ISO 15552 profile cylinder featuring a 125 mm bore, 500 mm stroke, and a SUS304 stainless steel piston rod. Delivering 6136 N push force at 0.5 MPa, it is replaced direct by the SAI125BX500FA. This upgrade shares the exact G1/2 port, M27x2 thread, and FA flange mounting interface. The SAI features an upgraded piston seal with two Y-shaped elements for low start-up pressure.
Because this SKU lacks the -S magnet, it cannot accept legacy CS1-B/DS1-B sensors. The 500 mm stroke requires external guides to prevent rod bending under side loads. For load holding on air loss, note that cushions only decelerate; use an external pilot check valve or the SAIL/BSAI lock variants.
Airtac SI125 Standard Cylinder SI125BX500FA Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125BX500FA |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125BX500FA |
| Bore size | Ø125 mm |
| Stroke | 500 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 SAI125BX500FA 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 SAI125BX500FA 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 SI125BX500FA
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×500 | 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 SI125BX500FA Is Used
Heavy Press Clamping
Secures large steel plates in hydraulic press beds, utilizing the 6136 N push force at 0.5 MPa to hold workpieces firmly during heavy industrial forming operations.
Pallet Lift Gates
Actuates robust lifting gates on automated palletizers, where the SUS304 stainless rod resists warehouse humidity and the 500 mm stroke provides ample vertical travel.
Bulk Material Diversion
Drives heavy-duty diverter arms on aggregate or mining conveyor lines, relying on adjustable 40 mm air cushions to decelerate the substantial moving load at stroke ends.
Replacing the Airtac SI125 Standard Cylinder SI125BX500FA with the SAI125BX500FA
To replace the discontinued SI125BX500FA, order the SAI125BX500FA, confirming the ISO 15552 FA flange interface, 125 mm bore, 500 mm stroke, and G1/2 port. This plain non-magnet SKU cannot take a sensor; if position detection is needed, select an SAI variant with the S magnet and current AirTAC switches. Sizing both ways: at 0.5 MPa it pushes 6136 N (pulls 5734 N); if you need less force, a 100 mm bore gives 3927 N push. For higher force, a 160 mm bore yields 10053 N. A plain cylinder drifts without live air—the cushion only decelerates—so for holding use a pilot check valve or the SAIL/BSAI lock variants. With a 500 mm stroke, always use external guides to manage rod-bending side loads. The SAI family also offers the SAIF self-valve (bores 32-100) which this size lacks.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125BX500FA
- ✓ 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 SI125BX500FA FAQ
Yes, the AirTAC SI125BX500FA is discontinued and end-of-life. The direct replacement is the SAI125BX500FA. It is dimensionally interchangeable per ISO 15552, retaining the same 125 mm bore, 500 mm stroke, G1/2 port, and FA flange mounting interface, so it fits existing fixtures directly.
This 125 mm bore double-acting cylinder features a G1/2 air port and an M27x2 rod thread. The thrust 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 force of 1251 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125BX500FA
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125BX500FA replacement — usually within 7-8 hours.