This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X85, 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 SI125X85
The AirTAC Airtac SI125 Standard Cylinder SI125X85 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 85mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125X85, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke85 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125X85
- 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 SI125X85
The AirTAC SI125X85 is a discontinued double-acting ISO 15552 profile cylinder featuring an extruded aluminum barrel, a 125 mm bore, and an 85 mm stroke. It delivers a robust 6136 N push force at 0.5 MPa, utilizing a G1/2 air port and an M27x2 rod thread. AirTAC replaced this legacy unit with the SAI125X85, a direct replacement retaining the exact ISO 15552 mounting interface, bore, output force, and port size to fit existing fixtures seamlessly.
The SAI125X85 upgrade introduces an advanced piston seal with two Y-shaped one-way elements for low start-up pressure and extended life. Note that this specific SKU lacks a magnet and cannot accept a sensor. If your application requires load holding on air loss, explore the SAIL or BSAI lock variants, as standard cushions only decelerate.
Airtac SI125 Standard Cylinder SI125X85 Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X85 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X85 |
| Bore size | Ø125 mm |
| Stroke | 85 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 SAI125X85 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 SAI125X85 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 SI125X85
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×85 | 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 SI125X85 Is Used
Heavy-Duty Stamping
Drives large press tools with 6136 N of thrust at 0.5 MPa, utilizing the 85 mm stroke for rapid metalforming cycles.
Automated Clamping
Secures oversized workholding fixtures in machining centers, relying on the rigid 32 mm piston rod for stable positioning.
Replacing the Airtac SI125 Standard Cylinder SI125X85 with the SAI125X85
To replace the discontinued SI125X85, order the SAI125X85, verifying your ISO 15552 mounting accessory (such as LB foot or TC trunnion) and the G1/2 port thread (PT, G, or NPT). This 125 mm bore yields 6136 N push and 5734 N pull at 0.5 MPa; if you need less force, neighboring bores like the 100 mm offer 3927 N push at the same pressure. Because this SKU is non-magnetic, it cannot support position sensing; add the -S suffix on your SAI order if you require CS1-B or DS1-B switches. Remember that a standard cylinder drifts without live air, so for load holding, select the SAIL air-released lock or BSAI clamp-lock variant instead of relying on the 40 mm adjustable cushions.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X85
- ✓ 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 SI125X85 FAQ
Yes, the AirTAC SI125X85 is discontinued. The direct replacement is the SAI125X85. It shares the identical ISO 15552 mounting interface, 125 mm bore, 85 mm stroke, force, and G1/2 port, fitting directly into your existing fixtures.
This double-acting cylinder uses a G1/2 air port and provides a push force of 6136 N and a pull force of 5734 N at 0.5 MPa. At 0.7 MPa the push force is 8590 N, and the theoretical maximum force is 1251 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125X85
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125X85 replacement — usually within 7-8 hours.