SU1544488A1 - Trunnion bearing for tumbling barrel - Google Patents

Abstract

The invention relates to mining equipment, in particular to trunnion supports of large-tonnage ore grinding grinding drum mills. The aim of the invention is to improve the reliability of operation and reduce power consumption. The support consists of a pin 1 of a drum 2, provided with collars 3, interacting with an insert 4, the support surface of which is spherical. Sphere center O ₁ is offset relative to the center O of symmetry of the journal portion situated between shoulders of the drum side by the amount L _sf defined by an expression of L _SF = N / ^P. R _c , where N is the axial force acting on the bearing shell from the drive of the mill

P is the radial force acting on the bearing liner of the weight of the mill

R _c is the pin radius. 2 Il.

Description

The invention relates to heavy machinery and can be used in units containing large-sized sliding bearings, in particular drum bearings of coal, rock and ore-grinding mills.

The purpose of the invention is to increase reliability and reduce power consumption.

In FIG. 1 shows the trunnion support of a drum mill, general view; in FIG. 2 is a diagram of the action of forces during the "self-installation" of the support during the first and second half of the revolution of the mill drum.

The mill support consists of a pin 1 / drum 2, a mill with thrust collars 3 in contact with the liner 4, / the supporting surface 5 of which is made / spherical and mounted on the counter spherical surface of the bearing housing 6.

The center of the spherical surface of the contribution / sha and the support of the thrust bearing, ^ placed on the axis of rotation of the mill, / is offset from the center of intersection of the longitudinal / and transverse axis of symmetry of the supporting part of the journal located between its shoulders, towards the drum by an amount determined from the expression

where / is the displacement of the center of the spherical surface of the bearing shell;

Λ '- axial force acting on the bearing from the drive;

P is the radial force acting on the bearing, from the weight of the mill;

g _h - radius of the trunnion of the drum of the mill. Due to the displacement of the center of the sphere of the liner and the support of the thrust bearing, equality of the moments of "self-installation" of the liner under the influence of axial force is achieved, which eliminates the loss of power consumption and increases the service life of the bearing, gearing and mill.

The support works as follows.

When the mill drum rotates, the support P is constantly affected by the force P from the weight of the drum with the load and the force Ν 'from the helical crown of the mill drive. The misalignment of the axle and the bearing and the presence of axial force acting through the collar of the axle on the bearing shell causes a moment in the first half of the mill revolution, which prevents the insert from self-installing

D4ir | = P - (/ c + / cf) —D '· r _c , where M „p | - the value of the moment preventing the self-installation of the liner;

P is the resultant of the pressure forces acting on the liner,

1c - eccentricity of the resultant pressure force;

/ sf is the eccentricity of the center of the sphere of the insert;

N is the axial force acting on the liner from the mill drive;

g _h is the radius of the trunnion.

In subsequent half-turns, an obstructing moment occurs

Μprp = P · (1c — 1ef) + N · Hz,

The eccentricity of the center of the sphere of the supporting surface of the liner ensures equal moments that impede the installation of the supporting liner for two consecutive half-turns of the mill. The absence of this eccentricity does not allow achieving the necessary equality of moments in the presence of axial force, and, accordingly, the installation moments.

Equating · Mnpi = M „pn, we obtain the indicated expression for determining the displacement of the center of the sphere of the bearing surface of the liner.

Compared with the known example of the angular contact support of the mill mill MSHR-4500X5000, the proposed angular contact support does not require additional manufacturing costs, increases the reliability of the mills in terms of ensuring the effect of "self-installation" in the presence of axial force and, accordingly, reduces the power consumed by the mill, increases the time bearing service, gearing, etc.

Claims (1)

Claim A trunnion support of a drum mill, comprising a trunnion bearing and an insert mating with it on a spherical bearing surface, in contact with the trunnions of the trunnion, characterized in that, in order to increase operational reliability and reduce power consumption, the center of the sphere of the bearing surfaces of the liner and bearing is offset from the intersection point the symmetry axes of the journal supporting part on its longitudinal axis in the direction of the drum, the offset value is determined from the relation i, a 'p' q ^z, where N - axial force on the bearing of the mill drive; P is the radial force on the mill bearing of its weight; Hz - trunnion radius. di