This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement B04-SAID50X250, 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 B04-SID Construction Machinery Special ISO Standard Cylinder B04-SID50X250
The AirTAC Airtac B04-SID Construction Machinery Special ISO Standard Cylinder B04-SID50X250 is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø50mm bore and 250mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the B04-SAID50X250, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ50 mm
- Stroke250 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM16×1.5
- StatusDiscontinued → B04-SAID50X250
- 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 B04-SID Construction Machinery Special ISO Standard Cylinder B04-SID50X250
The AirTAC B04-SID50X250 is a double-acting, double-rod ISO 15552 cylinder where the B04- prefix designates it as the construction-machinery dedicated variant of the base SID50X250. Because a rod exits both ends on one piston, both faces use the rod-side area, making push and pull force equal at 825 N @0.5 MPa, 1154 N @0.7 MPa, and 1484 N @0.9 MPa. It features a 50 mm bore, G1/4 air port, M16x1.5 rod thread, and 30 mm adjustable cushions at each end. This legacy model is discontinued and is directly replaced by the SAID50X250.
The direct replacement SAID50X250 shares the exact ISO 15552 interface, bore, stroke, and mounting, while adding an upgraded piston seal with two Y-shaped one-way elements for lower start-up pressure and longer life. The double-rod design prevents piston rotation and allows the back rod to drive a second tool. Note this SKU lacks a magnet (-S) and cannot take a sensor; air cushions only decelerate, so use an external rod lock for held loads.
Airtac B04-SID Construction Machinery Special ISO Standard Cylinder B04-SID50X250 Technical Specifications
| Model | Airtac B04-SID Construction Machinery Special ISO Standard Cylinder B04-SID50X250 |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | B04-SAID50X250 |
| Bore size | Ø50 mm |
| Stroke | 250 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 B04-SAID50X250 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 B04-SAID50X250 produces the same force from the same bore. Actual usable force is lower than theoretical; size with a margin.
Model Code: Airtac B04-SID Construction Machinery Special ISO Standard Cylinder B04-SID50X250
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 50 | Bore size in mm. |
| ×250 | 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 B04-SID Construction Machinery Special ISO Standard Cylinder B04-SID50X250 Is Used
Excavator Linkage Actuation
Uses the equal both-ways force and anti-rotation properties of the double rod to precisely shift heavy-equipment covers and guards on construction machinery without twisting.
Heavy-Equipment Fork Positioning
Drives dual mechanical linkages simultaneously from both rod ends, leveraging the 42 kg vertical lift capacity to adjust fork carriages on construction forklifts.
Crane Counterweight Shift
Applies the 825 N @0.5 MPa equal push/pull force to slide counterweight blocks along guides, relying on the rigid double-rod piston to prevent binding under offset loads.
Replacing the Airtac B04-SID Construction Machinery Special ISO Standard Cylinder B04-SID50X250 with the B04-SAID50X250
To replace the discontinued B04-SID50X250, specify the direct replacement SAID50X250, which preserves the ISO 15552 mounting interface, G1/4 port, and 250 mm stroke without mechanical changes. When sizing, remember the double-rod configuration provides equal force both ways (825 N @0.5 MPa), so if you need more thrust, step up to the 63 mm bore (1402 N @0.5 MPa) or down to the 40 mm bore (528 N @0.5 MPa). A double-rod cylinder is the right choice when you need anti-rotation stability or want to drive two tools from one piston. Mounting options include Basic, FA, LB, and TC. Since this SKU has no -S magnet, it cannot support sensing; if tracking is needed, select the SAID50X250-S and use CS1-B/DS1-B switches. For strokes of 300 mm or longer, carefully manage side-load alignment to prevent premature seal wear.
Replacement checklist
- ✓ Same ISO 15552 interface → B04-SAID50X250
- ✓ Same bore / stroke / force
- ✓ Port/thread type (PT/G/NPT)
- ✓ Magnet (-S) for sensors?
- ✓ Mounting reused (FA/FB/CA/CB/CR/LB/TC)
Airtac B04-SID Construction Machinery Special ISO Standard Cylinder B04-SID50X250 FAQ
Yes, the B04-SID50X250 (construction-machinery dedicated variant of SID50X250) is discontinued. The direct replacement is the SAID50X250, which shares the same ISO 15552 interface, 50 mm bore, 250 mm stroke, G1/4 port, and mounting. The SAI family also adds upgraded piston seals and SAIL/BSAI lock variants the SI line lacked.
Because it is a double-rod cylinder, force is equal both ways: 825 N @0.5 MPa, 1154 N @0.7 MPa, and 1484 N @0.9 MPa. The air port is G1/4, the rod thread is M16x1.5, and speed is 30-800 mm/s. The air cushion only decelerates near stroke end; it does not hold the load on air loss, so an external rod lock is required for held loads.
Related AirTAC SAI Cylinders
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