This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X680, 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 SI125X680
The AirTAC SI125 Standard Cylinder SI125X680 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 680mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125X680, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke680 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125X680
- 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 SI125X680
The AirTAC SI125X680 is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore and 680 mm stroke. It delivers 6136 N push and 5734 N pull at 0.5 MPa, operating through a G1/2 port. AirTAC replaced this legacy unit with the SAI125X680, a direct upgrade retaining the exact ISO 15552 mounting interface, bore, stroke, force, and port size.
The SAI replacement features an upgraded piston seal with two Y-shaped one-way elements for low start-up pressure and long life. Because this specific SKU lacks the -S magnet suffix, it cannot accept a CS1-B or DS1-B sensor.
Airtac SI125 Standard Cylinder SI125X680 Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X680 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X680 |
| Bore size | Ø125 mm |
| Stroke | 680 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 SAI125X680 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 SAI125X680 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 SI125X680
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×680 | 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 SI125X680 Is Used
Heavy Press Staging
Handles large automotive or metal stamping components into hydraulic presses, utilizing the 6136 N push force to position heavy blanks securely before forming.
Pallet Dispenser
Pushes empty or loaded pallets along roller conveyors in high-throughput distribution centers, where the 313 kg vertical lift capacity and 680 mm stroke clear pallet stacks easily.
Mold Actuation
Opens and closes large injection molding safety gates or heavy tooling fixtures, relying on the robust 32 mm rod and ISO 15552 profile barrel to handle industrial shock.
Replacing the Airtac SI125 Standard Cylinder SI125X680 with the SAI125X680
To replace the SI125X680, order the SAI125X680 and verify your ISO 15552 mounting accessories (LB, FA, TC, etc.), G1/2 port thread (PT, G, or NPT), and the M27x2 rod thread. When sizing, note a 100 mm bore provides 3927 N push at 0.5 MPa, while a 160 mm bore yields 10053 N. If you need to hold a load vertically without live air, a plain cylinder will drift; use an external pilot check valve, rod lock, or the SAIL/BSAI lock variants. The SAI family also adds the SAIF self-valve option. Because the 680 mm stroke is long, use an external guide to prevent rod bending and side-load damage. The 40 mm adjustable cushions decelerate the load but do not lock it.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X680
- ✓ 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 SI125X680 FAQ
Yes, the SI125X680 is discontinued. The direct replacement is the AirTAC SAI125X680. It is dimensionally interchangeable per ISO 15552, matching the 125 mm bore, 680 mm stroke, 6136 N force, G1/2 port, and mounting interface, so it drops directly into existing fixtures.
At 0.5 MPa it provides 6136 N push and 5734 N pull. At 0.7 MPa push is 8590 N, and at 0.9 MPa it is 11045 N. The theoretical max force is 1251 kgf at 1.0 MPa. Operating pressure is 0.15-1.0 MPa, speed is 30-500 mm/s, and it uses a G1/2 port with a 32 mm rod.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125X680
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125X680 replacement — usually within 7-8 hours.