This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125AX145, 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 SI125AX145
The AirTAC SI125 Standard Cylinder SI125AX145 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 145mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125AX145, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke145 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125AX145
- 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 SI125AX145
The AirTAC SI125AX145 is a discontinued double-acting ISO 15552 profile cylinder with a 125mm bore and 145mm stroke. It delivers 6136 N push force at 0.5 MPa via a G1/2 port. The direct replacement is the SAI125AX145, matching the exact bore, stroke, force, port and ISO 15552 mounting interface for existing fixtures.
The SAI upgrade features a two Y-shaped one-way piston seal for low start-up pressure and long life. This SI125AX145 variant uses a SUS420J2 stainless steel rod and lacks a magnet, so it cannot take a sensor.
Airtac SI125 Standard Cylinder SI125AX145 Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125AX145 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125AX145 |
| Bore size | Ø125 mm |
| Stroke | 145 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 SAI125AX145 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 SAI125AX145 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 SI125AX145
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×145 | 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 SI125AX145 Is Used
Heavy-Duty Pressing
Ideal for applying high clamping or pressing forces up to 6136 N in automated assembly lines, utilizing the 145mm stroke to secure heavy components.
Pallet Lift Stations
Handles robust vertical lifting tasks.
Large Fixture Actuation
Drives large mechanical fixtures and heavy-duty indexers where a 125mm bore is required to overcome significant initial mechanical friction and move substantial mass.
Replacing the Airtac SI125 Standard Cylinder SI125AX145 with the SAI125AX145
To replace the SI125AX145, order the SAI125AX145 keeping the SUS420J2 rod and ISO 15552 mounting. Confirm your port is G1/2. Since this SKU lacks a magnet (-S), it cannot accept position sensors; order a magnet-equipped version if you need CS1-B/DS1-B switches. The 145mm stroke is under 300mm so side-load risk is low, but always guide the load. For 6136 N at 0.5 MPa, neighboring bores are 100mm (3927 N) and 160mm (10053 N). A plain cylinder drifts on air loss; for load holding use an external pilot check valve or the SAIL/BSAI lock variants.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125AX145
- ✓ 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 SI125AX145 FAQ
Yes, the SI125AX145 is discontinued. The direct replacement is the AirTAC SAI125AX145. It is dimensionally interchangeable per ISO 15552, retaining the same 125mm bore, 145mm stroke, 6136 N output force, G1/2 port, and mounting interface.
This double-acting cylinder features a G1/2 air port, a 32mm piston rod, and an M27x2 rod thread. The force output 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, with a theoretical maximum of 1251 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125AX145
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125AX145 replacement — usually within 7-8 hours.