This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X315TC, 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 SI125X315TC
The AirTAC SI125 Standard Cylinder SI125X315TC is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 315mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125X315TC, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke315 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125X315TC
- 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 SI125X315TC
The AirTAC SI125X315TC is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore and 315 mm stroke. It delivers 6136 N push force at 0.5 MPa via a G1/2 port. The direct replacement is the SAI125X315TC, matching the exact bore, stroke, force, port and TC trunnion mounting interface.
The SAI upgrade features a two Y-shaped one-way piston seal for low start-up pressure and long life. This SKU lacks a magnet so it cannot take a sensor; legacy -S types used CS1-B/DS1-B switches. For high heat, Viton H seals raise the limit to 150 C.
Airtac SI125 Standard Cylinder SI125X315TC Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X315TC |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X315TC |
| Bore size | Ø125 mm |
| Stroke | 315 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 SAI125X315TC 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 SAI125X315TC 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 SI125X315TC
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×315 | 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 SI125X315TC Is Used
Heavy Press Operations
Applies 6136 N of thrust at 0.5 MPa for forming, stamping and heavy-duty press tasks within automated fabrication lines.
Pallet Diverting
Uses the TC trunnion mount and 315 mm stroke to push heavy pallets across high-throughput material handling conveyors.
Large Gate Actuation
Drives substantial bulkhead or loading dock gates requiring a robust 125 mm bore and extended 315 mm travel distance.
Replacing the Airtac SI125 Standard Cylinder SI125X315TC with the SAI125X315TC
To replace the SI125X315TC, order the SAI125X315TC and confirm the ISO 15552 TC trunnion interface, 125 mm bore, 315 mm stroke, G1/2 port (PT/G/NPT thread options) and M27x2 rod thread. Because this 315 mm stroke exceeds 300 mm, use an external guide to prevent rod bending and side-load wear. Sizing both ways: a neighbouring 100 mm bore gives 3927 N push at 0.5 MPa, while a 160 mm bore yields 10053 N. Note that a plain cylinder drifts on air loss; the 40 mm adjustable cushion only decelerates. For load holding, specify an external pilot check valve or the SAIL/BSAI lock variants. The SAI family also adds the SAIF self-valve variant for compact needs.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X315TC
- ✓ 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 SI125X315TC FAQ
Yes, the SI125X315TC is discontinued. The direct replacement is the SAI125X315TC. It is dimensionally interchangeable per ISO 15552, retaining the same bore, stroke, force, G1/2 port and TC mounting interface.
The 125 mm bore 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. Operating speed is 30-500 mm/s. The G1/2 port and M27x2 rod thread are fixed by the bore.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125X315TC
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125X315TC replacement — usually within 7-8 hours.