taper-bush
Product Deep-Dive
A QD weld-on hub is a fabrication component that brings a standard QD bushing interface into a plate, sprocket, sheave or other suitable steel assembly. The hub is welded to the fabricated component; the removable QD bushing is then installed in the finished taper-bored hub to mount the assembly on the shaft.
The EP technical data identifies QD Type 1 and Type 2 weld-on hub families from EP-JA-A through EP-S-A and states that the hubs are steel, drill-tapped and taper-bored for QD bushings. Type selection is part of the geometry, not a cosmetic choice.
How a QD weld-on hub works
The weld-on hub provides the outside fabrication surface and the internal QD taper. Once it is welded into the component, the selected QD bushing supplies the shaft bore and keyway. This modular arrangement lets a fabricated sprocket or plate share a standardized removable shaft interface.
Type 1 and Type 2 are different fabrication references
The catalogue groups weld-on hubs by Type 1 and Type 2 drilling/mounting arrangements. Before cutting the plate or preparing the weld joint, identify the exact hub type and QD size. Hole positions, outside diameter and mounting orientation should be taken from the correct drawing.
EP QD weld-on hub family
| EP hub reference | Matched QD family check | Fabrication note |
|---|---|---|
| EP-JA-A / EP-SH-A / EP-SDS-A / EP-SK-A | Confirm the matching smaller QD bushing family. | Use the exact D/L/B and bolt-circle drawing for the chosen hub. |
| EP-SF-A / EP-E-A / EP-F-A / EP-J-A | Confirm EP-SF/E/F/J QD interface. | Verify plate thickness, weld access and final alignment. |
| EP-M-A / EP-N-A / EP-P-A | Confirm EP-M/N/P QD interface. | Heavier hubs require controlled handling and distortion checks. |
| EP-W-A / EP-S-A | Confirm large QD interface. | Review component structure, weld procedure and final machining/alignment needs. |
Typical applications
Common uses include welding a QD hub into a plate sprocket for conveyor chain service, creating a fabricated belt sheave or fan hub, or adapting a custom steel plate to a standard QD shaft connection. The hub does not determine the application rating by itself; the welded assembly must be designed for the actual load.
Welding and post-weld checks
Use a welding procedure appropriate to the hub and parent component, controlling heat input and distortion. Do not weld with the removable QD bushing installed. After cooling, verify the hub has not pulled out of alignment and that the taper, threads and bolt pattern remain clean and undamaged before fitting the bushing.
Frequently asked questions
Can the QD bushing itself be welded to the plate?
No. The weld-on hub is the fabricated steel component; the QD bushing remains a removable shaft interface.
Are Type 1 and Type 2 interchangeable?
Do not assume so. Confirm the exact drawing, drilling/mounting arrangement and matched QD size before fabrication.
Related products and resources
Need help with a real application?
Send the model, shaft diameter, keyway or drawing so the enquiry can be checked against the correct bushing family.