Airtac SAIJ125 Adjustable Cylinder SAIJ125X550-20S
The AirTAC Airtac SAIJ125 Adjustable Cylinder SAIJ125X550-20S is a genuine double-acting ISO 15552 profile-barrel air cylinder with a Ø125mm bore and 550mm 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
- Stroke550 mm
- Port sizeG1/2
- Acting typeDouble acting
- Rod threadM27×2
- CushionAdjustable, 40 mm
About the Airtac SAIJ125 Adjustable Cylinder SAIJ125X550-20S
The AirTAC SAIJ125X550-20-S is a double-acting, single-rod ISO 15552 profile cylinder equipped with a rear stroke adjuster. It delivers a robust 6136N push force at 0.5 MPa, scaling up to 11045N at 0.9 MPa. The integrated -S magnet enables position detection using AirTAC CMSE reed or DMSE solid-state sensors housed in the dual-sided barrel grooves.
This specific SKU provides a 550 mm nominal stroke that can be dialed back by up to 20 mm, yielding a 530-550 mm usable travel window. This built-in adjuster acts purely as a mechanical stop to fine-tune the retract end position during commissioning; it does not hold the load without live air pressure. The standard carbon steel rod features an M27x2 thread, and the unit uses a PT tapered port.
Airtac SAIJ125 Adjustable Cylinder SAIJ125X550-20S Technical Specifications
| Model | Airtac SAIJ125 Adjustable Cylinder SAIJ125X550-20S |
|---|---|
| Series | SAI ISO 15552 profile cylinder |
| Bore size | Ø125 mm |
| Stroke | 550 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 SAIJ125X550-20S
| SAI | ISO 15552 profile-barrel cylinder series. |
|---|---|
| 125 | Bore size in mm. |
| ×550 | 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 SAIJ125X550-20S Is Used
Variable End-Stop Setup
Dial in the exact retract position within the 530-550 mm window during machine assembly without machining new spacers.
Product Size Changeover
Quickly adapt a packaging line to different carton lengths by turning the rear adjuster screw on the fly.
Heavy Press Positioning
Leverage the 6136N thrust at 0.5 MPa to move heavy jigs, using the fine-tune stop to prevent over-travel.
Is the Airtac SAIJ125 Adjustable Cylinder SAIJ125X550-20S the Right Cylinder?
Choose this 125 mm bore when an 80 mm cylinder (providing 2513N push at 0.5 MPa) lacks the thrust for heavy positioning tasks, but a 160 mm bore is physically oversized. The 20 mm adjustment window is ideal for product changeovers, allowing you to shift the end-stop without swapping the cylinder or adding external stops. For load-holding without continuous air, select a SAIL or BSAI cylinder instead, as this adjuster is not a lock.
Because the 550 mm stroke is substantial, the 32 mm rod diameter and M27x2 thread will handle high stresses, but an external guide is strongly recommended to prevent side-loading damage. To match this ISO 15552 replacement, verify the 125 mm bore, 550 mm stroke, 20 mm adjuster, PT G1/2 port, and the Basic, FA, LB, TC, FTC, TCM1, or TCM2 mounting style.
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 SAIJ125X550-20S FAQ
The rear adjuster acts as a mechanical stop that shortens the effective stroke by up to 20 mm, giving a 530-550 mm travel window. It is used for fine-tuning end positions at commissioning but does not lock or hold the load without live air.
It provides 6136N of push force and 5734N of pull force at 0.5 MPa. At 0.9 MPa, the push force increases to 11045N.
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Covers non-human-caused product damage.
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Standard models usually ship in 3-4 days.
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