This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement SAI50X770STC, 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 SI50X770STC
The AirTAC Airtac SI50 Standard Cylinder SI50X770STC is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 770mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the SAI50X770STC, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke770 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → SAI50X770STC
- 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 SI50X770STC
The AirTAC SI50X770STC is a discontinued double-acting ISO 15552 profile cylinder with a 50mm bore and 770mm stroke. Delivering 982N push at 0.5MPa via a G1/4 port, its direct replacement is the SAI50X770STC, retaining the identical TC trunnion mount and interface. The SAI upgrades the piston seal to two Y-shaped one-way elements for low start-up pressure and long life.
This unit includes a piston magnet for CS1-B/DS1-B switches. Note the SAI family adds SAIL lock, SAIF valve, and BSAI clamp variants absent in the SI line.
Airtac SI50 Standard Cylinder SI50X770STC Technical Specifications
| Model | Airtac SI50 Standard Cylinder SI50X770STC |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | SAI50X770STC |
| Bore size | Ø50 mm |
| Stroke | 770 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 SAI50X770STC 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 SAI50X770STC 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 SI50X770STC
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×770 | 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 SI50X770STC Is Used
Long-Stroke Diversion
Pushes packages across a 770mm transfer lane using the TC trunnion mount to accommodate the long stroke arc.
Vertical Material Lift
Raises a 50kg tote to an overhead platform, safely operating within the 589N working load margin at 0.5MPa.
Guard Door Actuation
Opens heavy machine safety doors over a wide 770mm span, relying on the adjustable 30mm air cushions for smooth deceleration.
Replacing the Airtac SI50 Standard Cylinder SI50X770STC with the SAI50X770STC
To replace the SI50X770STC, order the SAI50X770STC. Verify the ISO 15552 TC trunnion mount, 50mm bore, 770mm stroke, G1/4 port, and the -S magnet for current AirTAC switches. If you need more force, the 63mm bore yields 1559N push at 0.5MPa; if less, the 40mm bore gives 628N. Because this is a 770mm stroke, use an external guide to prevent rod bending and side loads. A plain cylinder drifts without air; for load holding, use an external rod lock, pilot check valve, or the SAIL/BSAI lock variant.
Replacement checklist
- ✓ Same ISO 15552 interface → SAI50X770STC
- ✓ 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 SI50X770STC FAQ
Yes, the SI50X770STC is discontinued. The direct replacement is the SAI50X770STC. It is dimensionally interchangeable per ISO 15552, retaining the same 50mm bore, 770mm stroke, TC mount, G1/4 port, and 982N force.
The 50mm bore features a G1/4 port and M16x1.5 rod thread. It delivers 982N push and 825N pull at 0.5MPa, 1374N push at 0.7MPa, 1767N push at 0.9MPa, and a maximum theoretical force of 200kgf at 1.0MPa.
Related AirTAC SAI Cylinders
Request a Quote for the SAI50X770STC
Send us the quantity and destination. We confirm price, stock and lead time on the SAI50X770STC replacement — usually within 7-8 hours.