This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50AX155, 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 SI50 Standard Cylinder SI50AX155
The AirTAC Airtac SI50 Standard Cylinder SI50AX155 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 155mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50AX155, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke155 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50AX155
- 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 SI50 Standard Cylinder SI50AX155
The AirTAC SI50AX155 is a discontinued double-acting ISO 15552 profile cylinder with a 50mm bore and 155mm stroke. It delivers 982N push force at 0.5MPa via a G1/4 port. The direct replacement is the SAI50AX155, matching the bore, stroke, force, port, and ISO 15552 mounting interface.
The SAI upgrade features a two Y-shaped one-way piston seal for low start-up pressure and long life. This SKU lacks a magnet (-S) so it cannot take a sensor, though legacy SI sensors were CS1-B/DS1-B. The -A rod is SUS420J2 stainless steel.
Airtac SI50 Standard Cylinder SI50AX155 Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50AX155 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50AX155 |
| Bore size | Ø50 mm |
| Stroke | 155 mm |
| Acting type | Double acting |
| Port size | G1/4 |
| Rod thread | M16×1.5 |
| 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 – 800 mm/s |
| Cushion | Adjustable, 30 mm |
| Max standard stroke | Up to 1200 mm |
Specifications follow the official AirTAC SI datasheet (now discontinued). The SAI50AX155 carries the same ISO 15552 ratings. Confirm against the product label before installation. Thread options: PT / G / NPT.
Theoretical Output Force (Ø50mm)
| Pressure | Push force | Pull force |
|---|---|---|
| 0.5 MPa | 982 N | 825 N |
| 0.7 MPa | 1374 N | — |
| Max (@1.0 MPa) | 200 kgf | |
The SAI50AX155 produces the same force from the same bore. Actual usable force is lower than theoretical; size with a margin.
Model Code: Airtac SI50 Standard Cylinder SI50AX155
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×155 | 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 SI50 Standard Cylinder SI50AX155 Is Used
Stainless Rod Clamping
Uses the SUS420J2 stainless piston rod to clamp parts in mildly corrosive environments, providing 982N of thrust at 0.5 MPa.
Package Diverting
Actuates diverters along a packaging line with a 155mm stroke, moving lightweight goods without needing position sensing.
Replacing the Airtac SI50 Standard Cylinder SI50AX155 with the SAI50AX155
To replace the SI50AX155, order the SAI50AX155. Confirm the ISO 15552 mounting interface, 50mm bore, 155mm stroke, G1/4 port, and SUS420J2 stainless rod. Because this SKU lacks a magnet, it cannot accept a sensor; if sensing is needed, order an SAI50A-S variant. To size both ways, a 40mm bore gives 628N push @0.5MPa, while a 63mm bore gives 1559N. A plain cylinder does not hold load without live air; for load holding use the SAIL lock, BSAI clamp-lock, or an external pilot check valve. Since the 155mm stroke is below 300mm, rod bending side-load risks are minimal.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50AX155
- ✓ Same bore / stroke / force
- ✓ Port/thread type (PT/G/NPT)
- ✓ Magnet (-S) for sensors?
- ✓ Mounting reused (FA/FB/CA/CB/CR/LB/TC)
Airtac SI50 Standard Cylinder SI50AX155 FAQ
Yes, the SI50AX155 is discontinued. The direct replacement is the SAI50AX155. It shares the same ISO 15552 mounting interface, 50mm bore, 155mm stroke, G1/4 port, and output force, fitting existing fixtures perfectly.
This 50mm bore double-acting cylinder uses a G1/4 air port. It generates 982N push and 825N pull at 0.5 MPa, 1374N push at 0.7 MPa, and a theoretical maximum of 200 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50AX155
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50AX155 replacement — usually within 7-8 hours.