This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50BX90, 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 SI50BX90
The AirTAC Airtac SI50 Standard Cylinder SI50BX90 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 90mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50BX90, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke90 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50BX90
- 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 SI50BX90
The AirTAC SI50BX90 is a discontinued double-acting ISO 15552 profile cylinder with a 50 mm bore, 90 mm stroke, and a SUS304 stainless steel piston rod. Generating 982 N push force at 0.5 MPa, it is replaced by the SAI50BX90 direct cylinder, retaining the same G1/4 port, M16x1.5 thread, and mounting interface. The SAI upgrade features an improved piston seal with two Y-shaped one-way elements for low start-up pressure and long life.
As this SKU lacks a magnet, it cannot accept a CS1-B or DS1-B sensor. The cushion only decelerates the load, so use a pilot check valve or the SAIL lock variant for load holding.
Airtac SI50 Standard Cylinder SI50BX90 Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50BX90 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50BX90 |
| Bore size | Ø50 mm |
| Stroke | 90 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 SAI50BX90 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 SAI50BX90 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 SI50BX90
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×90 | 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 SI50BX90 Is Used
Stainless Rod Clamping
Ideal for medium-force clamping tasks where the SUS304 rod resists moisture, providing 982 N of push force at 0.5 MPa.
Transfer Diverters
Drives 90 mm stroke diverting gates on packaging lines, matching the 50 mm bore ISO 15552 mounting footprint exactly.
Replacing the Airtac SI50 Standard Cylinder SI50BX90 with the SAI50BX90
To replace the discontinued SI50BX90, order the SAI50BX90. It drops into the same ISO 15552 fixtures, matching the 50 mm bore, 90 mm stroke, G1/4 port, and M16x1.5 rod thread. Confirm your mounting accessory (LB, FA, TC) and note that this no-magnet SKU cannot take a sensor. For sizing, the 50 mm bore yields 982 N push at 0.5 MPa; if you need less force, step down to a 40 mm bore (628 N), or step up to 63 mm (1559 N). Remember that a plain cylinder drifts on air loss; for load holding, use an external rod lock or the SAIL/BSAI variants. The SAI family also adds the SAIF self-valve option.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50BX90
- ✓ 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 SI50BX90 FAQ
Yes, the SI50BX90 is discontinued. The direct replacement is the SAI50BX90. It is dimensionally interchangeable per ISO 15552, keeping the same 50 mm bore, 90 mm stroke, G1/4 port, and mounting interface.
The G1/4 port bore delivers a push force of 982 N and pull of 825 N at 0.5 MPa. At 0.7 MPa push is 1374 N, and the theoretical max is 200 kgf at 1.0 MPa. Speed is 30-800 mm/s.
Request a Quote for the SAI50BX90
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50BX90 replacement — usually within 7-8 hours.