This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50X400H, 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 SI50X400H
The AirTAC SI50 Standard Cylinder SI50X400H is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 400mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50X400H, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke400 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50X400H
- 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 SI50X400H
The AirTAC SI50X400H is a discontinued double-acting ISO 15552 profile cylinder with a 50mm bore and 400mm stroke. It delivers 982N push force at 0.5MPa via a G1/4 port. The direct replacement is the SAI50X400H, matching the exact interface, stroke, and force.
The SAI upgrade features a two Y-shaped one-way piston seal for low start-up pressure. This SI50X400H variant uses Viton H seals for 0-150C high-temp environments. Being a no-S SKU, it lacks a magnet and cannot take a sensor.
Airtac SI50 Standard Cylinder SI50X400H Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50X400H |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50X400H |
| Bore size | Ø50 mm |
| Stroke | 400 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 SAI50X400H 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 SAI50X400H 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 SI50X400H
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×400 | 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 SI50X400H Is Used
High-Temperature Ejection
Ideal for pushing parts out of hot zones up to 150C using the Viton H seal, leveraging the 982N push force at 0.5 MPa over the 400mm travel.
Long-Stroke Diversion
Acts as a 400mm diverter arm on material handling lines, with external guides recommended to manage side loads during the extended stroke.
Replacing the Airtac SI50 Standard Cylinder SI50X400H with the SAI50X400H
To replace the SI50X400H, order the SAI50X400H direct, confirming the ISO 15552 mounting interface, G1/4 port, and 400mm stroke. This no-magnet SKU cannot accept CS1-B/DS1-B sensors. At 0.5MPa the 50mm bore yields 982N push; neighbouring 40mm yields 628N and 63mm yields 1559N. For load holding, note the air cushion only decelerates; use an external rod lock, pilot check valve, or SAIL/BSAI lock variant to prevent drift. With a 400mm stroke, use external guides to prevent rod bending and side-load damage.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50X400H
- ✓ 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 SI50X400H FAQ
Yes, the SI50X400H is discontinued. The direct replacement is the SAI50X400H. It is dimensionally interchangeable per ISO 15552, retaining the same 50mm bore, 400mm stroke, G1/4 port, and mounting fixtures.
The 50mm bore uses a G1/4 port. Force output is 982N push and 825N pull at 0.5 MPa, 1374N push at 0.7 MPa, and a theoretical maximum of 200 kgf at 1.0 MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50X400H
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50X400H replacement — usually within 7-8 hours.