This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125BX5, 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 SI125BX5
The AirTAC Airtac SI125 Standard Cylinder SI125BX5 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 5mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125BX5, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke5 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125BX5
- 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 SI125BX5
The AirTAC SI125BX5 is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore and 5 mm stroke. It delivered 6136 N push force at 0.5 MPa through a G1/2 port. The direct replacement is the SAI125BX5, which matches the exact bore, stroke, force, port and ISO 15552 mounting interface.
The SAI upgrade features a two Y-shaped one-way piston seal for low start-up pressure and long life. This specific SKU uses a SUS304 stainless steel rod (-B) for corrosion resistance but lacks a magnet, so it cannot accept position switches.
Airtac SI125 Standard Cylinder SI125BX5 Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125BX5 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125BX5 |
| Bore size | Ø125 mm |
| Stroke | 5 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 SAI125BX5 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 SAI125BX5 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 SI125BX5
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×5 | 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 SI125BX5 Is Used
High-Force Clamping
Provides intense 6136 N short-stroke clamping for heavy stamping or machining fixtures.
Press Ejection
Delivers robust 5 mm ejection thrust to knock out dense metal parts from press dies.
Pallet Stopping
Acts as a high-capacity end-stop for heavy loaded pallets on conveyor lines.
Replacing the Airtac SI125 Standard Cylinder SI125BX5 with the SAI125BX5
To replace the SI125BX5, order the SAI125BX5. Confirm the ISO 15552 mounting interface, 125 mm bore, 5 mm stroke, G1/2 port (PT/G/NPT thread options) and your specific mounting accessory. Because this SKU has no -S magnet, it cannot support legacy CS1-B/DS1-B sensors; if sensing is required, switch to a magnet-equipped SAI model. For loads needing holding on air loss, note that the standard cushion only decelerates and does not lock; use an external pilot check valve or the SAIL/BSAI lock variants. If increasing the stroke beyond 300 mm, add external guides to prevent rod bending under side loads. Neighbouring bores are 100 mm (3927 N push @0.5) and 160 mm (10053 N push @0.5).
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125BX5
- ✓ 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 SI125BX5 FAQ
Yes, the SI125BX5 is discontinued. The direct replacement is the SAI125BX5. It is dimensionally interchangeable per ISO 15552, retaining the same 125 mm bore, 5 mm stroke, output force, G1/2 port and mounting interface.
This double-acting cylinder uses a G1/2 port. It delivers 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 SAI125BX5
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125BX5 replacement — usually within 7-8 hours.