This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50BX375, 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 SI50BX375
The AirTAC Airtac SI50 Standard Cylinder SI50BX375 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 375mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50BX375, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke375 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50BX375
- 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 SI50BX375
The AirTAC SI50BX375 is a discontinued double-acting ISO 15552 profile cylinder with a 50mm bore, 375mm stroke, SUS304 stainless piston rod, and a G1/4 port. Delivering 982N push force at 0.5MPa, it is superseded by the SAI50BX375 direct replacement, matching the exact ISO 15552 mounting interface, bore, stroke, and output force.
The SAI upgrade features a two Y-shaped one-way piston seal for low start-up pressure and long life. Note this SKU lacks a magnet and cannot take a sensor; for load holding use the SAIL lock or a pilot check valve, as cushions only decelerate.
Airtac SI50 Standard Cylinder SI50BX375 Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50BX375 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50BX375 |
| Bore size | Ø50 mm |
| Stroke | 375 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 SAI50BX375 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 SAI50BX375 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 SI50BX375
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×375 | 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 SI50BX375 Is Used
Diverting Mechanisms
Drives routing gates on packaging lines using the 982N push force, with the SUS304 rod resisting humid or wash-down environments.
Controlled Lowering
Lowers 50kg work platforms vertically; requires external guides for the 375mm stroke and a pilot check valve to hold the load safely.
Pallet Handling
Indexes heavy pallets in distribution hubs, utilizing the adjustable 30mm air cushions to decelerate the payload smoothly at stroke ends.
Replacing the Airtac SI50 Standard Cylinder SI50BX375 with the SAI50BX375
To replace the SI50BX375, order the SAI50BX375. Confirm the ISO 15552 mounting interface (LB, FA, TC, etc.), the G1/4 port, and the 375mm stroke. Because this SKU lacks a magnet, it cannot accept CS1-B/DS1-B sensors; if sensing is needed, specify an SAI with the -S magnet option. At 0.5MPa the 50mm bore yields 982N push and 825N pull; sizing down, the 40mm bore offers 628N push, while sizing up, the 63mm bore provides 1559N push. For the 375mm stroke, use external guides to prevent rod bending and side loads. The cushion only decelerates; for load holding on air loss, use the SAIL or BSAI lock variants, or an external pilot check valve. The SAI family also adds the SAIF self-valve option.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50BX375
- ✓ 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 SI50BX375 FAQ
Yes, the SI50BX375 is discontinued. The direct replacement is the SAI50BX375. It shares the identical ISO 15552 mounting interface, 50mm bore, 375mm stroke, G1/4 port, and output force, fitting existing fixtures perfectly.
The G1/4 port is fixed by the 50mm bore. At 0.5MPa it provides 982N push and 825N pull; at 0.7MPa it pushes 1374N; at 0.9MPa it pushes 1767N. The theoretical maximum force is 200kgf at 1.0MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50BX375
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50BX375 replacement — usually within 7-8 hours.