This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50AX15, 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 SI50AX15
The AirTAC Airtac SI50 Standard Cylinder SI50AX15 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 15mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50AX15, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke15 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50AX15
- 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 SI50AX15
The AirTAC SI50AX15 is a discontinued double-acting ISO 15552 profile cylinder with a 50mm bore and 15mm stroke, delivering 982 N push force at 0.5 MPa. It is replaced by the SAI50AX15. This direct successor shares the exact ISO 15552 mounting interface, G1/4 port, and 200 kgf max force, fitting existing fixtures perfectly.
The SAI upgrade features a two Y-shaped one-way piston seal for low start-up pressure and long life. This SKU uses a SUS420J2 stainless rod (option A) but lacks a magnet, so it cannot take a CS1-B/DS1-B sensor. For high heat, Viton H seals raise the limit to 150 C.
Airtac SI50 Standard Cylinder SI50AX15 Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50AX15 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50AX15 |
| Bore size | Ø50 mm |
| Stroke | 15 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 SAI50AX15 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 SAI50AX15 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 SI50AX15
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×15 | 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 SI50AX15 Is Used
Short-Stroke Clamping
Ideal for tight clamping tasks where a 15mm stroke and 982 N force securely hold workpieces during machining operations.
Stainless Rod Ejection
The SUS420J2 stainless rod option provides corrosion resistance for ejecting parts in mildly humid or washdown environments.
Replacing the Airtac SI50 Standard Cylinder SI50AX15 with the SAI50AX15
To replace the SI50AX15, order the SAI50AX15. Confirm the ISO 15552 mounting interface, 50mm bore, 15mm stroke, G1/4 port, and SUS420J2 rod. Since this SKU lacks a magnet (-S), it cannot accept position sensors; add the S suffix if sensing is needed. For sizing, a 40mm bore yields 628 N push at 0.5 MPa, while a 63mm bore yields 1559 N. The air cushion only decelerates; it does not hold load on air loss. For held loads, use an external pilot check valve or the SAIL/BSAI lock variants. The SAIF variant integrates a 4M valve for bores 32-100.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50AX15
- ✓ 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 SI50AX15 FAQ
Yes, the SI50AX15 is discontinued. The direct replacement is the SAI50AX15. It shares the same ISO 15552 mounting interface, 50mm bore, 15mm stroke, output force, and G1/4 port, fitting existing fixtures directly.
The 50mm bore features a G1/4 port and M16x1.5 rod thread. It delivers 982 N push and 825 N pull at 0.5 MPa, 1374 N push at 0.7 MPa, 1767 N push at 0.9 MPa, and a theoretical max of 200 kgf at 1.0 MPa.
Request a Quote for the SAI50AX15
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50AX15 replacement — usually within 7-8 hours.