This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50X280, 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 SI50X280
The AirTAC Airtac SI50 Standard Cylinder SI50X280 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 280mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50X280, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke280 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50X280
- 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 SI50X280
The AirTAC SI50X280 is a discontinued double-acting ISO 15552 profile cylinder with a 50mm bore and 280mm stroke. It delivers a thrust of 982 N at 0.5 MPa. AirTAC replaced this legacy unit with the SAI50X280, a direct upgrade retaining the exact ISO 15552 mounting interface, bore, stroke, output force and G1/4 port size.
Because this specific SKU lacks the -S magnet suffix, it cannot accept a position sensor. The SAI upgrade features a refined piston seal with two Y-shaped one-way elements for low start-up pressure and extended life.
Airtac SI50 Standard Cylinder SI50X280 Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50X280 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50X280 |
| Bore size | Ø50 mm |
| Stroke | 280 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 SAI50X280 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 SAI50X280 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 SI50X280
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×280 | 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 SI50X280 Is Used
Package Diversion
Actuates routing gates on packaging lines, using the 280mm stroke to shift parcels smoothly between parallel conveyor belts.
Clamp Actuation
Provides reliable clamping force for mid-weight machining fixtures, utilizing the 982 N thrust to secure aluminium housings.
Vertical Lift Stops
Controls stopping mechanisms in low-force vertical material handling lifts, safely moving loads up to 50 kg.
Replacing the Airtac SI50 Standard Cylinder SI50X280 with the SAI50X280
To replace the SI50X280, order the SAI50X280. Confirm your ISO 15552 mounting accessory (LB foot, FA flange, TC trunnion) and port thread (PT, G or NPT) match. This 50mm bore yields 982 N push at 0.5 MPa; if undersized, the neighbouring 63mm bore offers 1559 N. At 280mm stroke, ensure adequate guidance to prevent rod bending and side-load wear. A standard cylinder drifts on air loss, so for load holding use an external pilot check valve or the SAIL lock variant. The SAI family also adds SAIF and BSAI options the SI lacked.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50X280
- ✓ 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 SI50X280 FAQ
Yes, the AirTAC SI50X280 is discontinued. The direct replacement is the SAI50X280, which shares the identical ISO 15552 mounting interface, 50mm bore, 280mm stroke, force and G1/4 port. It fits existing fixtures perfectly.
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 maximum is 200 kgf at 1.0 MPa. It operates at 30-800 mm/s with a 30mm adjustable air cushion.
Request a Quote for the SAI50X280
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50X280 replacement — usually within 7-8 hours.