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How to machine tapered journals in-situ


Ball mills and rotary kilns used in the mining industry consist of a hollow cylindrical shell rotating about its axis, with a large trunnion at each end for supporting the shell and its contents.

Considering the stresses involved, it comes as no surprise that the journal diameters on these trunnions eventually get worn, making the mill or kiln less effective or inoperable. To solve this problem, Mirage developed the SRB3000, which can re-machine worn journals in-situ in the vertical orientation, or in horizontally in a workshop environment.

Journal diameters on ball mills and roller kilns usually have a shallow taper, so it was essential that the machine was capable of machining angles suited to each different project. The machine shares some components with the Mirage MM3000i flange facer, but with a purpose designed arm assembly which can be set to suit the required trunnion angle.

 You can see the SRB3000 in action in the video below from when we recently tested one in our workshop.

Read the trunnion refurbishment case study here 

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