This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50AX165S, 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 SI50AX165S
The AirTAC SI50 Standard Cylinder SI50AX165S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 165mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50AX165S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke165 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50AX165S
- 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 SI50AX165S
The AirTAC SI50AX165S is a discontinued double-acting ISO 15552 profile cylinder with a 50 mm bore and 165 mm stroke. It delivers 982 N push force at 0.5 MPa through a G1/4 port. AirTAC replaced this legacy unit with the SAI50AX165S, a direct replacement retaining the exact ISO 15552 mounting interface, bore, stroke, output force, and port size.
The SAI upgrade features a modernized piston seal using two Y-shaped one-way elements for lower start-up pressure and extended life. This specific unit includes the -A SUS420J2 stainless steel piston rod for corrosion resistance and the -S magnet for legacy CS1-B/DS1-B sensors (the SAI replacement uses current AirTAC switches).
Airtac SI50 Standard Cylinder SI50AX165S Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50AX165S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50AX165S |
| Bore size | Ø50 mm |
| Stroke | 165 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 SAI50AX165S 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 SAI50AX165S 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 SI50AX165S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×165 | 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 SI50AX165S Is Used
Clamping Mechanisms
Ideal for mid-force clamping of workpieces in machining fixtures, utilizing the 982 N push force at 0.5 MPa with reliable G1/4 air supply.
Package Diverting
Deploys a 165 mm stroke to push or divert medium-weight cartons on a conveyor line, with the -S magnet confirming stroke end positions.
Replacing the Airtac SI50 Standard Cylinder SI50AX165S with the SAI50AX165S
To replace the SI50AX165S, order the SAI50AX165S. Verify your ISO 15552 mounting accessory (LB, FA, TC, etc.), the 165 mm stroke, and the G1/4 port. Because this SKU has the -S magnet, confirm your switch compatibility; the SAI family uses current AirTAC switches rather than the legacy CS1-B/DS1-B set. If sizing both ways, neighboring bores offer different force classes: a 40 mm bore provides 628 N push at 0.5 MPa, while a 63 mm bore yields 1559 N. Note that a plain ISO 15552 cylinder does not hold load without live air; the cushions only decelerate. For load holding, consider an external pilot check valve or the SAIL/BSAI lock variants. Since the 165 mm stroke is below 300 mm, standard side-load risks are minimal, but always guide the load to prevent rod bending.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50AX165S
- ✓ 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 SI50AX165S FAQ
Yes, the SI50AX165S is discontinued. The direct replacement is the AirTAC SAI50AX165S. It shares the identical ISO 15552 mounting interface, 50 mm bore, 165 mm stroke, output force, and G1/4 port, fitting directly into existing fixtures.
This double-acting cylinder features a G1/4 air port and an M16x1.5 rod thread. Theoretical forces are 982 N push and 825 N pull at 0.5 MPa, 1374 N push at 0.7 MPa, and a maximum of 200 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50AX165S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50AX165S replacement — usually within 7-8 hours.