Fretting wear reduction of interference fitted cone crusher head
A cone crusher head, system, and crusher including the cone crusher head and system. A conical mantle radially extends from an interference fit section and has a head diameter D ch . The conical mantle has a wear part support surface and a shaft support surface. The interference fit section has a nominal interference fit diameter D if . The conical mantle has an armpit groove for receiving a slip ring. The armpit groove is covered by the conical mantle with an armpit thickness L a . Fretting wear is reduced by dimensioning the crusher head so that a ratio of the head diameter D ch to the nominal interference fit diameter D if is most 2.5; and a ratio of the head diameter D ch to the armpit thickness L a is at least 10.5.
1 . A crusher head of a cone crusher, comprising:
a conical mantle radially extending from an interference fit section, comprising a wear part support surface and a shaft support surface;
the shaft support surface comprising the interference fit section for supporting the crusher head to a main shaft;
the interference fit section having a nominal interference fit diameter Dif;
the conical mantle comprising an armpit groove for receiving a slip ring;
the armpit groove being covered by the conical mantle with an armpit thickness La that is a minimum distance between a wear part support surface and the armpit; and
the conical mantle having a head diameter D ch that is a maximum diameter of the crusher head; wherein fretting wear is reduced by dimensioning of the crusher head for minimising deformations at the interference fit section by:
a ratio of the head diameter D ch to the nominal interference fit diameter D if being at most 2.5; and
a ratio of the head diameter D ch to the armpit thickness L a being at least 10.5.
2 . The crusher head of claim 1 , wherein the armpit groove is shaped so that both sides are free of constrictions.
3 . The crusher head of claim 1 , wherein the armpit groove has a rounded top section defined by a first portion of a first circle of a first radius, R 1 , and by a second portion of a second circle of a second radius, R 2 , wherein the second circle is vertically aligned with the first circle and R 2 >R 1 .
4 . The crusher head of claim 2 , wherein the armpit groove has a rounded top section defined by a first portion of a first circle of a first radius, R 1 , and by a second portion of a second circle of a second radius, R 2 , wherein the second circle is vertically aligned with the first circle and R 2 >R 1 .
5 . The crusher head of claim 3 , wherein the first circle extends below the interference fit section.
6 . The crusher head of claim 4 , wherein the first circle extends below the interference fit section.
7 . The crusher head of claim 1 , wherein interference fit section has a longitudinal length of at least 50% of the longitudinal length Lch of the cone crusher head.
8 . The crusher head of claim 1 , wherein the first portion of the first circle extends on an outer side of the armpit groove at most vertically to a level of the first centre.
9 . The crusher head of claim 1 , wherein a bottom of the inner side of the armpit groove is aligned with the interference fit section.
10 . The crusher head of claim 1 , wherein
an inner side of the armpit groove approaches a bottom of the interference fit section with a deviation angle from the central axis; and
the deviation angle is at most 30 degrees.
11 . The crusher head of claim 1 , wherein an outer side of the armpit groove meets an intermediate surface with an angle greater than 270 degrees.
12 . The crusher head of claim 1 , wherein the crusher head is configured to be laterally supported by the main shaft only by the interference fit section.
13 . A system comprising the crusher head of claim 1 and the main shaft of a cone crusher, the main shaft comprising
an interference fit section for supporting a crusher head, the interference fit section having a nominal interference fit diameter D if ;
a bottom shaft section extending between a bottom end of the main shaft and the interference fit section;
the bottom shaft section comprising a bottom part and a neck part;
wherein the bottom part has a bottom part length L bp and a bottom part diameter D bp that is constant below the neck part on at least 50% of the bottom part length L bp ;
the neck part has a neck part diameter that is growing towards the interference fit section; and
the main shaft has a main shaft length L ms ;
wherein for reducing fretting wear in the interference fit section,
L ms 1.3 /D if is at most 40 mm 0.3 ; and
D bp 1.421 /D if is at most 9.0 mm 0.421 .
14 . The system of claim 13 , wherein the main shaft length L ms is at least 1200 mm.
15 . The system of claim 13 , wherein D bp 1.421 /D if is at most 8.0 mm 0.421 .
16 . The system of claim 14 , wherein D bp 1.421 /D if is at most 8.0 mm 0.421 .
17 . The system of claim 13 , wherein the main shaft is configured to laterally support the crusher head only by the interference fit section of the main shaft.
18 . The system of claim 14 , wherein the main shaft is configured to laterally support the crusher head only by the interference fit section of the main shaft.
19 . The system of claim 15 , wherein the main shaft is configured to laterally support the crusher head only by the interference fit section of the main shaft.
20 . A cone crusher comprising the system of claim 13 .