This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50BX290S, 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 SI50BX290S
The AirTAC Airtac SI50 Standard Cylinder SI50BX290S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 290mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50BX290S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke290 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50BX290S
- 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 SI50BX290S
The AirTAC SI50BX290S is a discontinued double-acting ISO 15552 profile cylinder with a 50 mm bore and 290 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 SAI50BX290S, which preserves the exact ISO 15552 mounting interface, M16x1.5 rod thread, and force ratings.
The SAI upgrade introduces a two Y-shaped one-way piston seal for low start-up pressure and long life. This specific SKU features a SUS304 stainless steel rod (-B) and a piston magnet (-S) for legacy CS1-B/DS1-B sensors.
Airtac SI50 Standard Cylinder SI50BX290S Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50BX290S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50BX290S |
| Bore size | Ø50 mm |
| Stroke | 290 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 SAI50BX290S 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 SAI50BX290S 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 SI50BX290S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×290 | 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 SI50BX290S Is Used
Package Diverting
The 290 mm stroke provides the extended reach needed to push packages cleanly off a production line at speeds up to 800 mm/s.
Lab Equipment
The -B SUS304 stainless piston rod offers corrosion resistance, making it suitable for sterile or wash-down laboratory automation tasks.
Replacing the Airtac SI50 Standard Cylinder SI50BX290S with the SAI50BX290S
To replace the SI50BX290S, order the SAI50BX290S. Confirm the ISO 15552 mounting interface, 50 mm bore, 290 mm stroke, G1/4 port, and your mounting accessory (LB, FA, TC, etc.). Because this SKU includes -S, it has a piston magnet for CS1-B/DS1-B switches; the SAI replacement uses current AirTAC switches. The -B code specifies a SUS304 stainless rod for corrosion resistance, unlike the standard carbon steel. At 290 mm stroke, use a guide to prevent rod bending and side-load wear. Sizing options: 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 without live air; for load holding, use an external rod lock, pilot check valve, or the SAIL/BSAI lock variants.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50BX290S
- ✓ 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 SI50BX290S FAQ
Yes, the SI50BX290S is discontinued. The direct replacement is the SAI50BX290S. It shares the same ISO 15552 mounting interface, 50 mm bore, 290 mm stroke, G1/4 port, and output force, fitting existing fixtures perfectly.
This double-acting cylinder has a G1/4 air port. The thrust ratings are: 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; with a theoretical maximum force of 200 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50BX290S
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50BX290S replacement — usually within 7-8 hours.