Airtac SAIJ125 Adjustable Cylinder SAIJ125X300-20S
The AirTAC Airtac SAIJ125 Adjustable Cylinder SAIJ125X300-20S is a genuine double-acting ISO 15552 profile-barrel air cylinder with a Ø125mm bore and 300mm stroke, G1/2 air ports and adjustable end cushioning. Its standardized mounting interface makes it a drop-in replacement for other ISO 15552 cylinders in automation lines.
- BoreØ125 mm
- Stroke300 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2
- CushionAdjustable, 40 mm
About the Airtac SAIJ125 Adjustable Cylinder SAIJ125X300-20S
The AirTAC SAIJ125X300-20-S is a double-acting, single-rod ISO 15552 profile cylinder equipped with a rear stroke adjuster. It provides a nominal 300 mm stroke that can be dialed back by up to 20 mm, creating a precise 280-300 mm usable travel window for commissioning without external stops. In the 125 mm bore class, it delivers 6136 N of pull force at 0.5 MPa, making it suitable for heavy-duty positioning tasks.
This variant includes a magnet for position detection and is fully compatible with AirTAC CMSE reed and DMSE electronic solid-state sensors that seat directly into the dual-side extruded aluminum barrel grooves. The carbon steel rod features an M27x2 thread, and the unit omits the FB, CA, CB, and CR mounting formats, utilizing a focused set of Basic, FA, LB, TC, FTC, TCM1, and TCM2 accessories.
Airtac SAIJ125 Adjustable Cylinder SAIJ125X300-20S Technical Specifications
| Model | Airtac SAIJ125 Adjustable Cylinder SAIJ125X300-20S |
|---|---|
| Series | SAI ISO 15552 profile cylinder |
| Bore size | Ø125 mm |
| Stroke | 300 mm |
| Acting type | Double acting |
| Port size | G1/2 |
| Rod thread | M27×2 |
| 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 – 500 mm/s |
| Cushion | Adjustable, 40 mm |
| Max stroke | Up to 1500 mm |
Specifications follow the official AirTAC SAI series datasheet and ISO 15552 dimensions. Confirm against the product label before installation. Port options: G (BSPP) / NPT.
Theoretical Output Force (Ø125mm)
| Pressure | Push force | Pull force |
|---|---|---|
| 0.5 MPa | 6136 N | 5734 N |
| 0.7 MPa | 8590 N | — |
| Max (@1.0 MPa) | 1251 kgf | |
Actual usable force is lower than theoretical due to friction and back-pressure. Size with a safety margin.
Model Code: Airtac SAIJ125 Adjustable Cylinder SAIJ125X300-20S
| SAI | ISO 15552 profile-barrel cylinder series. |
|---|---|
| 125 | Bore size in mm. |
| ×300 | Stroke length in mm. |
| -S | Optional built-in magnet for sensor position sensing. |
Related SAI-family variants: SAID (double rod), SAIJ (adjustable stroke), SAIL (with lock), SAIF (with valve), BSAI (enclasp / clamp-lock), and SAI-S with built-in magnet. Rod material: carbon steel (blank) / SUS420J2 (A) / SUS304 (B); seals: TPU (blank) / Viton H / NBR N.
Where the Airtac SAIJ125 Adjustable Cylinder SAIJ125X300-20S Is Used
Variable End-Stop Setup
Dial in the exact 280-300 mm travel distance during machine commissioning to accommodate different product lengths without swapping hardware.
Product Changeover
Quickly adjust the retract stop position on a packaging line to handle varying package sizes on the fly.
Heavy Assembly Positioning
Leverage the 6136 N pull force at 0.5 MPa to move heavy pallets or fixtures into their final machined position.
Is the Airtac SAIJ125 Adjustable Cylinder SAIJ125X300-20S the Right Cylinder?
Choose this 125 mm bore when a 63 mm bore (1402 N pull at 0.5 MPa) is insufficient for moving heavy assemblies, but a 160 mm bore (9425 N pull at 0.5 MPa) would be excessive overkill. The adjustable stroke is selected over a fixed-stroke SAI model when a machine requires variable end-stops or fine-tuning during product changeovers. The rear adjuster acts purely as a travel stop and does not hold the load without live air pressure; for fail-safe load holding, consider an external rod lock or the SAIL series.
When replacing an ISO 15552 cylinder, match the 125 mm bore, 300 mm stroke, 20 mm adjustment range, PT tapered port thread, and the -S magnet option. Because the 300 mm stroke is relatively long for this bore size, an external guide is recommended to prevent excessive side-loading on the M27x2 rod.
Quick checklist
- ✓ Required force at your working pressure
- ✓ Stroke and mounting space
- ✓ Port/thread type (PT/NPT/G)
- ✓ Magnet (-S) for sensors?
- ✓ Side load — consider a guided cylinder
Installation & Maintenance Notes
- check Use clean air filtered to 40µm or finer.
- check Keep within 0.15 – 1.0 MPa operating pressure.
- check Avoid side load on the piston rod.
- check Adjust end cushion screws for smooth stops.
- check Use correct mounting accessory (FA/FB/CA/CB/LB/TC).
- check Installation by qualified personnel per AirTAC docs.
Airtac SAIJ125 Adjustable Cylinder SAIJ125X300-20S FAQ
At 0.5 MPa operating pressure, this 125 mm bore cylinder provides 6136 N of pull force and 8590 N of push force. It can deliver a maximum of 1251 kgf at 1.0 MPa.
The external rear screw allows you to shorten the effective travel by up to 20 mm from the 300 mm nominal stroke, yielding a 280-300 mm usable window. This stopper fine-tunes the end position but does not lock the load without live air.
Authorized Export Seller
Genuine AirTAC parts produced by AirTAC factory.
1-Year Warranty
Covers non-human-caused product damage.
Fast Dispatch
Standard models usually ship in 3-4 days.
Fast Reply
Most inquiries answered within 7-8 hours.
Related AirTAC SAI Cylinders
Request a Quote for Airtac SAIJ125 Adjustable Cylinder SAIJ125X300-20S
Send us the quantity and destination. We confirm price, stock and lead time — usually within 7-8 hours.