This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50X157, 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 SI50X157
The AirTAC Airtac SI50 Standard Cylinder SI50X157 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 157mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50X157, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke157 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50X157
- 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 SI50X157
The AirTAC SI50X157 is a discontinued double-acting ISO 15552 profile cylinder with a 50mm bore and 157mm stroke. It delivers 982N push force at 0.5MPa via a G1/4 port. AirTAC replaced this legacy unit with the SAI50X157 direct replacement, featuring the same interface, force, and mounting dimensions.
This stroke length is non-standard. The SAI upgrade utilizes an upgraded piston seal with two Y-shaped one-way elements for low start-up pressure and long life. Since this SKU lacks a magnet, it cannot accept a sensor. For load holding, note the cushion only decelerates; use the SAIL or BSAI lock variants for secure holding.
Airtac SI50 Standard Cylinder SI50X157 Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50X157 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50X157 |
| Bore size | Ø50 mm |
| Stroke | 157 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 SAI50X157 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 SAI50X157 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 SI50X157
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×157 | 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 SI50X157 Is Used
Package Diverting
Actuates routing gates on packaging lines using the 982N push force at 0.5MPa to redirect cartons efficiently.
Pallet Stops
Controls pallet movement on roller conveyors, decelerating loads with its 30mm adjustable air cushions at both ends.
Replacing the Airtac SI50 Standard Cylinder SI50X157 with the SAI50X157
To replace the discontinued SI50X157, order the SAI50X157. Confirm the ISO 15552 mounting interface, 50mm bore, 157mm non-standard stroke, G1/4 port (PT/G/NPT), and mounting accessory. Because this SKU lacks the -S magnet, it cannot take a CS1-B/DS1-B sensor; switch to a current AirTAC switch if needed. Sizing both ways: a 40mm bore gives 628N push @0.5MPa, while a 63mm bore gives 1559N. For holding loads without air, use the SAIL lock, BSAI clamp-lock, or external pilot check valve. For this 157mm stroke, ensure guide alignment to prevent rod bending.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50X157
- ✓ 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 SI50X157 FAQ
Yes, the SI50X157 is discontinued. The direct replacement is the AirTAC SAI50X157. It is dimensionally interchangeable per ISO 15552, matching the 50mm bore, 157mm stroke, G1/4 port, and mounting interface. The SAI features an upgraded piston seal for lower start-up pressure.
The 50mm bore features a G1/4 air port and M16x1.5 rod thread. Force output is 982N push and 825N pull at 0.5MPa, 1374N push at 0.7MPa, and a theoretical max of 200kgf at 1.0MPa. Operating speed is 30-800mm/s.
Request a Quote for the SAI50X157
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50X157 replacement — usually within 7-8 hours.