This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X216, 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 SI125X216
The AirTAC SI125 Standard Cylinder SI125X216 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 216mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125X216, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke216 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125X216
- 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 SI125X216
The AirTAC SI125X216 is a discontinued double-acting ISO 15552 profile cylinder with a 125 mm bore and 216 mm stroke. It delivers 6136 N push force at 0.5 MPa via a G1/2 port. The direct replacement is the SAI125X216, matching the interface, bore, stroke, force, and mounting. Note that 216 mm is a nonstandard stroke length.
The SAI upgrade introduces a two Y-shaped one-way piston seal for low start-up pressure and long life. Because this SKU lacks a magnet (-S), it cannot accept CS1-B/DS1-B sensors. The SAI family also adds SAIL and BSAI lock variants absent in the SI line.
Airtac SI125 Standard Cylinder SI125X216 Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X216 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X216 |
| Bore size | Ø125 mm |
| Stroke | 216 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 SAI125X216 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 SAI125X216 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 SI125X216
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×216 | 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 SI125X216 Is Used
Heavy Duty Pressing
Applies the 6136 N push force at 0.5 MPa for seating large bearings or assembling heavy structural components.
Pallet Handling
Drives robust lifting and positioning mechanisms in automated storage systems using the 216 mm stroke.
Large Mold Clamping
Secures substantial injection molds or machining fixtures, utilizing the 32 mm rod for structural stability.
Replacing the Airtac SI125 Standard Cylinder SI125X216 with the SAI125X216
To replace this SI125X216, order the SAI125X216 direct. Confirm the ISO 15552 mounting interface, the 216 mm nonstandard stroke, the G1/2 port (PT/G/NPT), and your mounting accessory. Since this SKU has no -S magnet, it cannot support position sensing; order a magnet-equipped SAI if needed. For sizing, the 125 mm bore yields 6136 N push at 0.5 MPa; if lower force is acceptable, a 100 mm bore provides 3927 N. Because the 216 mm stroke exceeds 300 mm, ensure adequate guide support to prevent rod bending and side-load wear. A plain cylinder drifts on air loss; for load holding, use an external rod lock, a pilot check valve, or the SAIL/BSAI lock variant.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X216
- ✓ 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 SI125X216 FAQ
Yes, the SI125X216 is discontinued. The direct replacement is the SAI125X216. It is dimensionally interchangeable per the ISO 15552 mounting interface, retaining the same 125 mm bore, 216 mm stroke, output force, G1/2 port, and mounting accessories.
This double-acting cylinder uses a G1/2 port. The thrust is 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, with a theoretical maximum of 1251 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125X216
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125X216 replacement — usually within 7-8 hours.