This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X400TC, 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 SI125X400TC
The AirTAC SI125 Standard Cylinder SI125X400TC is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 400mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125X400TC, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke400 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125X400TC
- 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 SI125X400TC
The AirTAC SI125X400TC is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore and 400 mm stroke. It delivers 6136 N push force at 0.5 MPa. The direct replacement is the SAI125X400TC, matching the TC trunnion mount, G1/2 port, and 30-500 mm/s speed.
This SKU lacks the -S magnet and cannot accept a sensor. The SAI upgrade features two Y-shaped one-way piston seals for low start-up pressure. For high heat, Viton H seals raise the temperature limit to 150 C.
Airtac SI125 Standard Cylinder SI125X400TC Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X400TC |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X400TC |
| Bore size | Ø125 mm |
| Stroke | 400 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 SAI125X400TC 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 SAI125X400TC 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 SI125X400TC
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×400 | 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 SI125X400TC Is Used
Heavy Press Forming
Applies the 6136 N push force at 0.5 MPa for stamping and forming dense metal components in automated fabrication lines.
Pallet Diversion
Leverages the 400 mm stroke and TC trunnion mount to push heavy loaded pallets cleanly across transfer sections without side-loading the rod.
Bulk Lift Gates
Raises and lowers heavy material handling gates, using the 125 mm bore's 5734 N pull force to manage substantial vertical counterweights.
Replacing the Airtac SI125 Standard Cylinder SI125X400TC with the SAI125X400TC
To replace the SI125X400TC, order the SAI125X400TC. Verify the ISO 15552 TC trunnion mount, 400 mm stroke, and G1/2 port. Since this SKU has no -S magnet, it cannot hold a switch; if sensing is needed, select an SAI model with S. Neighbouring bores are 100 mm (3927 N @0.5) and 160 mm (10053 N @0.5). The 400 mm stroke requires an external guide to prevent rod bending under side loads. A plain cylinder drifts on air loss; use a SAIL lock or pilot check valve to hold loads.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X400TC
- ✓ 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 SI125X400TC FAQ
Yes, the SI125X400TC is discontinued. The direct replacement is the SAI125X400TC. It is dimensionally interchangeable per ISO 15552, preserving the 125 mm bore, 400 mm stroke, G1/2 port, and TC trunnion mounting interface.
The G1/2 port feeds a 32 mm rod. At 0.5 MPa it pushes 6136 N and pulls 5734 N. 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.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125X400TC
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125X400TC replacement — usually within 7-8 hours.