This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X185, 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 SI125X185
The AirTAC SI125 Standard Cylinder SI125X185 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 185mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125X185, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke185 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125X185
- 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 SI125X185
The AirTAC SI125X185 is a discontinued double-acting ISO 15552 profile cylinder. Generating 6136 N push force at 0.5 MPa, it features a 125 mm bore, 185 mm stroke, G1/2 port, and M27x2 rod thread. The direct replacement is the SAI125X185, matching the exact ISO 15552 mounting interface, bore, stroke, output force, and porting.
Upgrading to the SAI125X185 introduces an upgraded piston seal with two Y-shaped one-way elements for low start-up pressure and extended life. For applications needing load holding, the SAI family adds SAIL and BSAI lock variants the SI lacked. As this specific SKU lacks a magnet (-S), it cannot accept position sensors.
Airtac SI125 Standard Cylinder SI125X185 Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X185 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X185 |
| Bore size | Ø125 mm |
| Stroke | 185 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 SAI125X185 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 SAI125X185 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 SI125X185
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×185 | 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 SI125X185 Is Used
Heavy-Duty Pressing
Applies the 6136 N push force at 0.5 MPa to seat bearings or form light-gauge metal components in automated fabrication cells.
Pallet Handling
Drives robust lifting arms in packaging lines, utilizing the 313 kg vertical lift capacity to elevate heavy goods safely.
Clamp Actuation
Secures large workpieces on machining centers, relying on the 32 mm rod and ISO 15552 profile to withstand machining forces.
Replacing the Airtac SI125 Standard Cylinder SI125X185 with the SAI125X185
To replace the SI125X185, order the SAI125X185. Verify your ISO 15552 mounting accessory (LB, FA, CA, TC) and thread type (PT, G, or NPT) for a seamless fixture direct. Because this SKU has no -S magnet, it cannot support CS1-B/DS1-B sensors; order an SAI with S if sensing is required. For sizing alternatives, dropping to a 100 mm bore reduces force to 3927 N at 0.5 MPa, while increasing to 160 mm yields 10053 N. Operating speed is 30-500 mm/s. Since this is a plain double-acting cylinder, the 40 mm air cushions only decelerate the load near stroke end; they do not hold position on air loss. For secure load holding, specify an external pilot check valve, rod lock, or the SAIL/BSAI lock variant.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X185
- ✓ 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 SI125X185 FAQ
Yes, the SI125X185 is discontinued. The direct replacement is the AirTAC SAI125X185. It matches the ISO 15552 mounting interface, 125 mm bore, 185 mm stroke, G1/2 port, and output force, fitting existing fixtures perfectly.
The G1/2 port 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. It operates at 30-500 mm/s with a 40 mm adjustable cushion.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125X185
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125X185 replacement — usually within 7-8 hours.