This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI125X50CA, 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 SI125X50CA
The AirTAC SI125 Standard Cylinder SI125X50CA is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø125mm bore and 50mm stroke, G1/2 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI125X50CA, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ125 mm
- Stroke50 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2.0
- StatusDiscontinued → SAI125X50CA
- 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 SI125X50CA
The AirTAC SI125X50CA is a discontinued double-acting ISO 15552 profile cylinder delivering 6136 N push force at 0.5 MPa through a 125 mm bore and 50 mm stroke. AirTAC replaced it with the SAI125X50CA direct upgrade, retaining the exact CA clevis mounting, G1/2 port, and M27x2 rod thread. The new model features an upgraded piston seal with two Y-shaped one-way elements for lower start-up pressure and longer life.
Because this specific SKU lacks the -S magnet suffix, it cannot accept position sensors like the legacy CS1-B or DS1-B switches. For higher temperature environments up to 150 C, you can specify the Viton H seal option on the replacement. Note that a standard cylinder relies on live air to hold load; the 40 mm adjustable air cushions only decelerate the piston near stroke end. For true load holding on air loss, explore the SAIL or BSAI lock variants.
Airtac SI125 Standard Cylinder SI125X50CA Technical Specifications
| Model | Airtac SI125 Standard Cylinder SI125X50CA |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI125X50CA |
| Bore size | Ø125 mm |
| Stroke | 50 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 SAI125X50CA 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 SAI125X50CA 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 SI125X50CA
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 125 | Bore size in mm. |
| ×50 | 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 SI125X50CA Is Used
Heavy Stamping Press
Drives a 125 mm bore tooling head providing 6136 N of push force at 0.5 MPa to form thick gauge metal components securely.
Pallet Gate Actuator
Shifts heavy loaded pallets on a conveyor line using the robust CA clevis mount to handle high lateral articulation safely.
Mold Clamping Station
Holds large industrial molds in place during machining, utilizing the short 50 mm stroke for rapid, high-force clamping cycles.
Replacing the Airtac SI125 Standard Cylinder SI125X50CA with the SAI125X50CA
To replace the discontinued SI125X50CA, order the SAI125X50CA. It is dimensionally interchangeable per the ISO 15552 mounting interface, matching the 125 mm bore, 50 mm stroke, CA clevis mount, and G1/2 port. Confirm your port thread (PT, G, or NPT) and rod material (carbon steel, SUS420J2, or SUS304) when ordering. If you need position sensing, select an SAI variant with the -S magnet option, as this no-S legacy SKU cannot accept a switch. Sizing both ways: the 125 mm bore gives 6136 N push at 0.5 MPa, while the neighbouring 100 mm bore offers 3927 N; step up to 160 mm for 10053 N if your fixture needs more power. The cylinder operates at 30-500 mm/s. Since a plain cylinder drifts without air pressure, use an external rod lock or pilot check valve for load holding. The 50 mm stroke is short, so side-load rod-bending stress is minimal.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI125X50CA
- ✓ 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 SI125X50CA FAQ
Yes, the AirTAC SI125X50CA is discontinued. The direct replacement is the SAI125X50CA. It features the same ISO 15552 mounting interface, 125 mm bore, 50 mm stroke, CA clevis mount, and G1/2 port, fitting existing fixtures perfectly while upgrading the piston seal.
The 125 mm bore features a G1/2 air port and delivers 6136 N push and 5734 N pull at 0.5 MPa. At 0.7 MPa it pushes 8590 N, and at 0.9 MPa it pushes 11045 N. The theoretical maximum force is 1251 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI125X50CA
Send us the quantity and destination. We confirm price, stock and lead time on the SAI125X50CA replacement — usually within 7-8 hours.