This model is discontinued
AirTAC has phased out the SI series. You can still order this code here: we ship the direct replacement B04-SAID40X125S, 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-SID40X125S
The AirTAC Airtac B04-SID Construction Machinery Special ISO Standard Cylinder B04-SID40X125S is a double-acting ISO 15552 (orig. ISO 6431) profile-barrel cylinder with a Ø40mm bore and 125mm stroke, G1/4 air ports and adjustable end cushioning. This model is discontinued — the direct replacement is the B04-SAID40X125S, which matches its ISO interface, bore, stroke, force and mounting.
- BoreØ40 mm
- Stroke125 mm
- Port sizeG1/4
- Acting typeDouble acting
- Rod threadM12×1.25
- StatusDiscontinued → B04-SAID40X125S
- 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-SID40X125S
The AirTAC B04-SID40X125S is a double-acting, double-rod ISO 15552 cylinder where a rod exits both ends, ensuring push and pull force is equal both ways (528 N at 0.5 MPa). The B04- prefix marks this as a construction-machinery dedicated variant of the base SID40X125S; mechanically, every spec matches the base cylinder exactly. This discontinued model drops in directly with the SAID40X125S, which retains the G1/4 port, M12x1.25 rod thread, and 27 mm adjustable cushions.
Because the second rod can drive two tools or carry a sensor cam, it offers superior anti-rotation stability for heavy-equipment builders. The SAI replacement upgrades the piston seal to two Y-shaped one-way elements for lower start-up pressure. Note that air cushions only decelerate; use an external rod lock or SAIL variant to hold loads on air loss.
Airtac B04-SID Construction Machinery Special ISO Standard Cylinder B04-SID40X125S Technical Specifications
| Model | Airtac B04-SID Construction Machinery Special ISO Standard Cylinder B04-SID40X125S |
|---|---|
| Series | SI ISO 15552 profile cylinder (discontinued) |
| Replacement | B04-SAID40X125S |
| Bore size | Ø40 mm |
| Stroke | 125 mm |
| Acting type | Double acting |
| Port size | G1/4 |
| Rod thread | M12×1.25 |
| 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, 27 mm |
| Max standard stroke | Up to 1200 mm |
Specifications follow the official AirTAC SI datasheet (now discontinued). The B04-SAID40X125S carries the same ISO 15552 ratings. Confirm against the product label before installation. Thread options: PT / G / NPT.
Theoretical Output Force (Ø40mm)
| Pressure | Push force | Pull force |
|---|---|---|
| 0.5 MPa | 628 N | 528 N |
| 0.7 MPa | 880 N | — |
| Max (@1.0 MPa) | 128 kgf | |
The B04-SAID40X125S 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-SID40X125S
| SI | ISO 15552 profile-barrel cylinder (discontinued). |
|---|---|
| 40 | Bore size in mm. |
| ×125 | 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-SID40X125S Is Used
Excavator Linkage Control
Drives dual-action mechanical linkages on construction machinery where equal push and pull force is mandatory for precise boom positioning.
Heavy-Equipment Transfer
Powers a double-ended transfer mechanism on an assembly line for heavy-equipment components, using the back rod to carry a sensor cam.
Mast Synchronization
Synchronizes two lifting points on a materials handler mast, leveraging the anti-rotation properties of the double-rod design to prevent binding.
Replacing the Airtac B04-SID Construction Machinery Special ISO Standard Cylinder B04-SID40X125S with the B04-SAID40X125S
To replace the B04-SID40X125S, specify the SAID40X125S—it matches the 40 mm bore, 125 mm stroke, G1/4 port, and ISO 15552 mounting interface (Basic, FA, LB, TC). When sizing both ways, compare neighbouring bores: the 32 mm bore yields 345 N at 0.5 MPa, while the 50 mm bore yields 825 N. Choose this double-rod cylinder when you need equal force in both directions or anti-rotation guidance. The -S suffix indicates a piston magnet for legacy CS1-B/DS1-B switches. For strokes of 300 mm or longer, verify side-load bearing limits. Operating speed is 30-800 mm/s.
Replacement checklist
- ✓ Same ISO 15552 interface → B04-SAID40X125S
- ✓ 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-SID40X125S FAQ
Yes, the B04-SID40X125S (construction-machinery dedicated variant of SID40X125S) is discontinued. The direct replacement is the SAID40X125S. It shares the same ISO 15552 interface, 40 mm bore, 125 mm stroke, G1/4 port, and equal-both-ways force, but uses an upgraded two Y-shaped one-way piston seal.
Force is equal both ways at 528 N @0.5 MPa, 739 N @0.7 MPa, and 950 N @0.9 MPa. Speed is 30-800 mm/s. The G1/4 port and 27 mm adjustable cushions manage deceleration, but the cylinder will not hold a load on air loss without an external rod lock.
Related AirTAC SAI Cylinders
Request a Quote for the B04-SAID40X125S
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