This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X25SLB, 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 SI125X25SLB
The AirTAC SI125 Standard Cylinder SI125X25SLB is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 25mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125X25SLB, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke25 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125X25SLB
- 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 SI125X25SLB
The AirTAC SI125X25SLB is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore and 25 mm stroke. It delivers 6136 N push force at 0.5 MPa through a G1/2 port. The direct replacement is the SAI125X25SLB, matching the bore, stroke, force, port and LB foot mounting interface.
The SAI upgrade features a new piston seal with two Y-shaped one-way elements for low start-up pressure and long life. The SAI family also adds SAIL and BSAI lock variants the SI lacked.
Airtac SI125 Standard Cylinder SI125X25SLB Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X25SLB |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X25SLB |
| Bore size | Ø125 mm |
| Stroke | 25 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 SAI125X25SLB 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 SAI125X25SLB 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 SI125X25SLB
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×25 | 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 SI125X25SLB Is Used
Heavy Press Clamping
Applies 6136 N of thrust at 0.5 MPa to secure heavy metal workpieces in machining fixtures.
Stamping Ejection
Short 25 mm stroke rapidly ejects dense stamped parts from a press bed using an LB foot mount.
Pallet Stopper Gate
Acts as a high-force pneumatic stop for heavy pallets on conveyor lines, holding against significant inertia.
Replacing the Airtac SI125 Standard Cylinder SI125X25SLB with the SAI125X25SLB
To replace the SI125X25SLB, order the SAI125X25SLB. Confirm the ISO 15552 LB foot mounting, 125 mm bore, 25 mm stroke, G1/2 port, and the -S magnet for CS1-B/DS1-B sensors. If you need more force, the 160 mm bore offers 10053 N push at 0.5 MPa; if less is required, the 100 mm bore provides 3927 N. A plain cylinder drifts on air loss—the cushion only decelerates—so use an external rod lock or pilot check valve for load holding. The SAI family offers SAIL and BSAI lock variants for secure holding.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X25SLB
- ✓ 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 SI125X25SLB FAQ
Yes, the SI125X25SLB is discontinued. The direct replacement is the SAI125X25SLB. It is dimensionally interchangeable per ISO 15552, retaining the same 125 mm bore, 25 mm stroke, G1/2 port, LB foot mount, and output force.
It uses a G1/2 port. The thrust is 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 maximum theoretical force of 1251 kgf at 1.0 MPa. The operating speed is 30-500 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125X25SLB
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125X25SLB replacement — usually within 7-8 hours.