This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50X168, 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 SI50X168
The AirTAC Airtac SI50 Standard Cylinder SI50X168 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 168mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50X168, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke168 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50X168
- 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 SI50X168
The AirTAC SI50X168 is a discontinued double-acting ISO 15552 profile cylinder with a 50 mm bore and 168 mm stroke. It delivers 982 N push and 825 N pull at 0.5 MPa through a G1/4 port. The direct replacement is the SAI50X168, 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 nonstandard 168 mm stroke SKU lacks a magnet (-S), so it cannot take CS1-B/DS1-B sensors.
Airtac SI50 Standard Cylinder SI50X168 Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50X168 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50X168 |
| Bore size | Ø50 mm |
| Stroke | 168 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 SAI50X168 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 SAI50X168 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 SI50X168
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×168 | 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 SI50X168 Is Used
Package Diversion
Pushes parcels off a sorting line using the 982 N push force at 0.5 MPa, with the 168 mm stroke clearing guide rails.
Clamp Actuation
Holds workpieces in a machining fixture, where the 825 N pull force at 0.5 MPa secures the part during light milling.
Pallet Stopper
Acts as a pneumatic stop for incoming pallets, absorbing impact via the 30 mm adjustable air cushions at both ends.
Replacing the Airtac SI50 Standard Cylinder SI50X168 with the SAI50X168
To replace the SI50X168, order the SAI50X168. Verify the ISO 15552 mounting interface (LB, FA, TC, etc.), the G1/4 port, and the M16x1.5 rod thread. Because this is a nonstandard 168 mm stroke, confirm exact end-of-stroke positioning. This SKU has no magnet, meaning CS1-B/DS1-B switches cannot be fitted; order an -S variant if sensing is required. For sizing, a 40 mm bore gives 628 N push at 0.5 MPa, while a 63 mm bore yields 1559 N. Note that a plain cylinder drifts on air loss; for load holding, use an external pilot check valve or the SAIL/BSAI lock variants.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50X168
- ✓ 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 SI50X168 FAQ
Yes, the SI50X168 is discontinued. The direct replacement is the SAI50X168. It is dimensionally interchangeable per ISO 15552, retaining the same 50 mm bore, 168 mm stroke, 982 N force, G1/4 port and mounting accessories.
It features a G1/4 port. The thrust is 982 N push and 825 N pull at 0.5 MPa, 1374 N push at 0.7 MPa, and a theoretical maximum of 200 kgf at 1.0 MPa. Operating speed is 30-800 mm/s.
Request a Quote for the SAI50X168
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50X168 replacement — usually within 7-8 hours.