This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X350H, 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 SI125X350H
The AirTAC SI125 Standard Cylinder SI125X350H is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 350mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125X350H, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke350 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125X350H
- 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 SI125X350H
The AirTAC SI125X350H is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore and 350 mm stroke. It delivers 6136 N push force at 0.5 MPa, uses a G1/2 port, and features a high-temperature Viton H seal rated for 0 to 150 C. Because this SKU lacks a magnet, it cannot accept position switches. The direct replacement is the SAI125X350H.
The SAI125X350H matches the bore, stroke, force, port, and ISO 15552 mounting interface, dropping directly into existing fixtures. It upgrades the piston seal to two Y-shaped one-way elements for lower start-up pressure and longer life.
Airtac SI125 Standard Cylinder SI125X350H Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X350H |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X350H |
| Bore size | Ø125 mm |
| Stroke | 350 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 SAI125X350H 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 SAI125X350H 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 SI125X350H
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×350 | 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 SI125X350H Is Used
Heavy Stamping Press
Drives heavy-duty stamping actuators where the 6136 N push force at 0.5 MPa and 350 mm stroke accommodate large material displacement.
High-Tact Foundry Ejector
Ejects cast components in hot environments, leveraging the Viton H seals rated for 0 to 150 C to withstand ambient radiant heat.
Pallet Positioning Gate
Shifts heavy loaded pallets via a 313 kg vertical lift capacity, requiring external guide rails to manage the 350 mm stroke side loads.
Replacing the Airtac SI125 Standard Cylinder SI125X350H with the SAI125X350H
To replace the SI125X350H, order the SAI125X350H and verify your ISO 15552 mounting interface, G1/2 port, and M27x2 rod thread. Confirm the Viton H high-temperature seal requirement. Since this is a non-magnet SKU, it cannot support CS1-B/DS1-B sensors; add the S suffix if sensing is needed. The 350 mm stroke demands external guides to prevent rod bending under side loads. For load holding on air loss, note that the air cushion only decelerates; use an external pilot check valve or the SAIL/BSAI lock variants. Neighbouring bores: 100 mm gives 3927 N push, while 160 mm yields 10053 N at 0.5 MPa.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X350H
- ✓ 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 SI125X350H FAQ
Yes, the SI125X350H is discontinued. The direct replacement is the SAI125X350H. It shares the exact same ISO 15552 mounting interface, 125 mm bore, 350 mm stroke, G1/2 port, and Viton H seal option, fitting existing fixtures perfectly without modifications.
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. The operating speed is 30-500 mm/s.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125X350H
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125X350H replacement — usually within 7-8 hours.