This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50X170S, 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 SI50X170S
The AirTAC Airtac SI50 Standard Cylinder SI50X170S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 170mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50X170S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke170 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50X170S
- 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 SI50X170S
The AirTAC SI50X170S is a discontinued double-acting ISO 15552 profile cylinder featuring a 50mm bore and 170mm stroke. It delivers 982N push and 825N pull at 0.5MPa through a G1/4 port. AirTAC replaced this legacy unit with the SAI50X170S, a direct sharing the exact interface, bore, stroke, output force and mounting.
The SAI upgrade introduces a two Y-shaped one-way piston seal for low start-up pressure and longevity. For applications needing load holding on air loss, the new SAIL or BSAI lock variants fill gaps the SI lacked. This -S SKU includes a piston magnet for CS1-B/DS1-B sensors; the SAI uses current AirTAC switches.
Airtac SI50 Standard Cylinder SI50X170S Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50X170S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50X170S |
| Bore size | Ø50 mm |
| Stroke | 170 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 SAI50X170S 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 SAI50X170S 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 SI50X170S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×170 | 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 SI50X170S Is Used
Mid-Force Clamping
Ideal for holding medium workpieces during machining, utilising the 982N push force at 0.5MPa with the 170mm stroke to clear fixtures.
Package Diversion
Drives sorting gates or pusher arms on packaging lines, where the 50kg vertical lift capacity and 30-800mm/s speed ensure rapid actuation.
Pallet Lift Stops
Functions as a reliable stop or positioning gate in material handling, benefiting from the direct ISO 15552 profile barrel for existing frames.
Replacing the Airtac SI50 Standard Cylinder SI50X170S with the SAI50X170S
To replace the SI50X170S, order the SAI50X170S. Verify the ISO 15552 mounting interface, 50mm bore, 170mm stroke, G1/4 port (PT/G/NPT thread) and mounting accessory. The -S suffix denotes a magnet for legacy CS1-B/DS1-B sensors; the SAI takes current AirTAC switches. Sizing both ways: a neighbouring 63mm bore yields 1559N push at 0.5MPa, while dropping to 40mm gives 628N. Remember, a plain cylinder drifts on air loss—the cushion only decelerates. For held loads, use an external rod lock, pilot check valve, or the SAIL/BSAI lock variant. Rod material options include carbon steel, SUS420J2 (A) or SUS304 (B).
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50X170S
- ✓ 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 SI50X170S FAQ
Yes, the SI50X170S is discontinued. The direct replacement is the AirTAC SAI50X170S. It shares the identical ISO 15552 mounting interface, 50mm bore, 170mm stroke, output force, G1/4 port and mounting accessories, fitting directly into existing fixtures.
The 50mm bore features a G1/4 air port and M16x1.5 rod thread. Force ratings are: 982N push and 825N pull at 0.5MPa, 1374N push at 0.7MPa, 1767N push at 0.9MPa, and a theoretical max of 200kgf at 1.0MPa. Adjustable air cushion is 30mm.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50X170S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50X170S replacement — usually within 7-8 hours.