This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50AX5, 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 SI50AX5
The AirTAC Airtac SI50 Standard Cylinder SI50AX5 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 5mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50AX5, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke5 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50AX5
- 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 SI50AX5
The AirTAC SI50AX5 is a discontinued double-acting ISO 15552 profile cylinder with a 50mm bore and 5mm stroke, delivering 982N push force at 0.5MPa. The direct replacement is the SAI50AX5, matching the bore, stroke, G1/4 port, M16x1.5 thread and ISO 15552 mounting interface. This SKU features a SUS420J2 stainless steel rod (-A) but lacks a magnet, so it cannot accept a CS1-B/DS1-B sensor.
The SAI upgrade introduces a two Y-shaped one-way piston seal for low start-up pressure and long life. The SAI family also adds SAIL, SAIF and BSAI lock variants the SI line lacked.
Airtac SI50 Standard Cylinder SI50AX5 Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50AX5 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50AX5 |
| Bore size | Ø50 mm |
| Stroke | 5 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 SAI50AX5 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 SAI50AX5 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 SI50AX5
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×5 | 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 SI50AX5 Is Used
Short-Stroke Clamping
Ideal for holding stainless steel workpieces in machining fixtures using the corrosion-resistant SUS420J2 rod and 982N clamping force.
Ejector Mechanism
Provides a fast 5mm ejection stroke for small parts in automated assembly lines, operating at speeds between 30-800 mm/s.
Valve Actuation
Suitable for toggling small process valves or diverters where a compact 50mm bore and short travel are required.
Replacing the Airtac SI50 Standard Cylinder SI50AX5 with the SAI50AX5
To replace this SI50AX5, order the SAI50AX5 and confirm the ISO 15552 mounting interface, 50mm bore, 5mm stroke, G1/4 port and SUS420J2 rod. Because this SKU has no -S magnet, it cannot hold a switch; order a magnet-equipped SAI if you need sensing. When sizing, a 40mm bore yields 628N push at 0.5MPa while a 63mm bore yields 1559N, so pick based on your load. Remember this plain cylinder will not hold a load without live air; the 30mm cushions only decelerate. For load holding, use an external pilot check valve or the SAIL/BSAI lock variants.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50AX5
- ✓ 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 SI50AX5 FAQ
Yes, the AirTAC SI50AX5 is discontinued. The direct replacement is the SAI50AX5. It is dimensionally interchangeable per ISO 15552, keeping the same 50mm bore, 5mm stroke, G1/4 port and mounting interface.
This double-acting cylinder has a G1/4 air port. It delivers 982N push and 825N pull at 0.5MPa, 1374N push at 0.7MPa, 1767N push at 0.9MPa, and a theoretical max of 200 kgf at 1.0MPa.
Request a Quote for the SAI50AX5
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50AX5 replacement — usually within 7-8 hours.