This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X5S, 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 SI125X5S
The AirTAC SI125 Standard Cylinder SI125X5S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 5mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125X5S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke5 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125X5S
- 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 SI125X5S
The AirTAC SI125X5S is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore and 5 mm stroke. Delivering 6136 N push force at 0.5 MPa, it is replaced directly by the SAI125X5S. This direct successor keeps the G1/2 port, M27x2 thread, and mounting dimensions intact.
The SAI upgrade features a two Y-shaped one-way piston seal for low start-up pressure. The original SI line lacked the SAIL lock, SAIF valve, and BSAI clamp variants now available.
Airtac SI125 Standard Cylinder SI125X5S Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X5S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X5S |
| Bore size | Ø125 mm |
| Stroke | 5 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 SAI125X5S 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 SAI125X5S 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 SI125X5S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×5 | 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 SI125X5S Is Used
Short-Stroke Clamping
Ideal for high-force, short-travel clamping of heavy steel plates in machining fixtures.
Part Ejection
Provides robust ejection force for dense molded parts, utilizing the 6136 N thrust at 0.5 MPa.
Press Insertion
Handles short downward pressing of bearings or pins, safely managing a 313 kg vertical lift load.
Replacing the Airtac SI125 Standard Cylinder SI125X5S with the SAI125X5S
To replace the SI125X5S, order the SAI125X5S to retain the exact ISO 15552 interface, 5 mm stroke, and G1/2 port. Confirm your mounting accessory (LB, FA, or TC) and thread option (PT/G/NPT). The -S suffix indicates a piston magnet for legacy CS1-B/DS1-B sensors; the SAI replacement uses current AirTAC switches. For sizing, neighbouring bores (100/160 mm) offer different force classes, while this 125 mm bore yields 6136 N at 0.5 MPa. Note that a plain cylinder drifts without live air; for load holding, use an external rod lock, pilot check valve, or the SAIL/BSAI lock variants.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X5S
- ✓ 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 SI125X5S FAQ
Yes, the AirTAC SI125X5S is discontinued. The direct replacement is the SAI125X5S. It shares the same ISO 15552 mounting interface, 125 mm bore, 5 mm stroke, output force, and G1/2 port, fitting existing fixtures perfectly.
The 125 mm bore uses a G1/2 air port. It generates 6136 N push and 5734 N pull at 0.5 MPa, 8590 N push at 0.7 MPa, 11045 N at 0.9 MPa, and a maximum theoretical force of 1251 kgf at 1.0 MPa. The rod is 32 mm with an M27x2 thread.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125X5S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125X5S replacement — usually within 7-8 hours.