This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X1200STC, 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 SI125X1200STC
The AirTAC SI125 Standard Cylinder SI125X1200STC is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 1200mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125X1200STC, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke1200 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125X1200STC
- 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 SI125X1200STC
The AirTAC SI125X1200STC is a discontinued double-acting ISO 15552 profile cylinder with a 125mm bore, 1200mm stroke, TC trunnion mount and a built-in magnet. Delivering 6136N push force at 0.5MPa, it features a 32mm rod, M27x2 thread and G1/2 port. The direct replacement is the SAI125X1200STC, matching the interface, force and mounting exactly.
The SAI upgrade introduces a two Y-shaped one-way piston seal for low start-up pressure and long life. The SAI family also adds SAIL, SAIF and BSAI lock variants absent from the SI line. This legacy -S SKU used CS1-B/DS1-B sensors, while the SAI takes current AirTAC switches.
Airtac SI125 Standard Cylinder SI125X1200STC Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X1200STC |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X1200STC |
| Bore size | Ø125 mm |
| Stroke | 1200 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 SAI125X1200STC 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 SAI125X1200STC 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 SI125X1200STC
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×1200 | 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 SI125X1200STC Is Used
Heavy Material Transfer
Drives large pallets or heavy fixtures over 1200mm on assembly lines using 6136N thrust at 0.5MPa.
Automated Warehousing
Actuates multi-tier pushers and diverter gates where the TC trunnion mount handles pivotal load shifts.
Large Press Feeding
Feeds heavy blanks into presses, relying on the 32mm rod and external guides to handle the long 1200mm extension.
Replacing the Airtac SI125 Standard Cylinder SI125X1200STC with the SAI125X1200STC
To replace this SI with the SAI125X1200STC, verify the ISO 15552 TC trunnion interface, 125mm bore, 1200mm stroke, G1/2 port and magnet. You can size both ways: step down to an 80mm bore for 2513N push at 0.5MPa, or up to 160mm for 10053N. A plain cylinder drifts on air loss, as the 40mm cushion only decelerates; use an external rod lock, pilot check valve or the SAIL/BSAI lock variant for holding. At 1200mm, prevent rod bending by using an external guide to absorb side loads. Rod options include carbon steel, SUS420J2 (A) or SUS304 (B); Viton H seals raise heat to 150C.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X1200STC
- ✓ 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 SI125X1200STC FAQ
Yes, the SI125X1200STC is discontinued. The direct replacement is the SAI125X1200STC. It is dimensionally interchangeable per ISO 15552, keeping the same 125mm bore, 1200mm stroke, TC mount, G1/2 port and 6136N force, so it fits existing fixtures directly.
The G1/2 port and 32mm rod deliver 6136N push and 5734N pull at 0.5MPa, 8590N push at 0.7MPa, 11045N at 0.9MPa, and a 1251kgf max at 1.0MPa. Speed is 30-500mm/s. The -S magnet works with legacy CS1-B/DS1-B sensors; the SAI uses current switches.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125X1200STC
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125X1200STC replacement — usually within 7-8 hours.