A rotary milking platform 1 has a deck 2, a circular upper beam 4 connected to and supporting the deck, a circular lower beam 6 and a series of carriages 5 connected end to end to form a ring between the beams. The platform is formed such that the upper beam 4 is arranged to rest and rotate on the ring of carriages 5 to rotate the deck 2. Each carriage has at least one carriage roller 10, and each roller 10 arranged to rotate on the lower beam 4. Each roller 10 also has a retention flange 11 at only one side. The flanges 11 of some of the rollers 10 are at or adjacent an inner side of the ring, and the flanges 11 of others of the rollers are at or adjacent an outer side of the ring. The rollers 10 of the ring are arranged such that at least one roller is oriented with its flange 11 on an opposite side to another of the flanged rollers immediately adjacent to it. The flanges prevent the carriages from moving off the lower beam 4 when the platform 1 is in use. Further, at least some of the carriages can be disconnected from the ring and swung laterally to be moved free of the beams 4, 6 for maintenance, repair or replacement.

A laser welding apparatus (1) includes a laser welding head (5) configured to irradiate a workpiece (10) with laser light, a welding filler feeding mechanism (6) configured to supply a welding material to a position on which laser welding is performed, and a hollow structural moving mechanism (100) configured to move a welding unit (50) including the laser welding head and the welding filler feeding mechanism. The hollow structural moving mechanism has an insertion portion (3a) through which wire materials (41 and 62) of the laser welding head and the welding filler feeding mechanism are inserted.

A laser welding apparatus (1) includes a laser welding head (5) configured to irradiate a workpiece (10) with laser light, a welding filler feeding mechanism (6) configured to supply a welding material to a position on which laser welding is performed, and a hollow structural moving mechanism (100) configured to move a welding unit (50) including the laser welding head and the welding filler feeding mechanism. The hollow structural moving mechanism has an insertion portion (3a) through which wire materials (41 and 62) of the laser welding head and the welding filler feeding mechanism are inserted.

A speed change device comprising an inner race having an outer surface, an outer race having an inner surface, and set of orbital rollers including inner rollers in rolling contact with the outer surface of the inner race and outer rollers in rolling contact with the inner surface of the outer race.

A pinned roller bearing assembly having a plurality of pinned rollers, wherein each of the pins has a first threaded end received in a threaded aperture of a first support ring, and a second unthreaded and shouldered end received in a countersunk and unthreaded aperture of a second support ring. Each end of each pin extends through its respective support ring and is rivetingly domed outside the support ring to secure its position and configuration. The pinned roller bearings and support rings are disposed within an outer and inner race.

A pinned roller bearing assembly and cage wherein the pin has two ends, a first end received in a first support ring, and a second end received in a second support ring, the pin comprising a threaded portion at one of the first or second ends, and the other end which is not threaded, or at least one shouldered end for engaging a countersunk support ring, or both a threaded end and one or both ends being shouldered.

A roller bearing assembly for use in a fracking pump crank shaft includes an inner ring being positioned an outer ring and a plurality of rolling elements disposed therebetween. Each of the rolling elements have a bore extending therein. The roller bearing assembly includes a cage having an annular disc with pins extending axially inward therefrom and into the bore. The pins are positioned on the annular disc so that the rolling elements are spaced apart from one another with a gap extending continuously therebetween. The gap is of a predetermined magnitude to maximize the number of rolling elements that fit between the inner ring and the outer ring to maximize load carrying capacity of the roller bearing assembly.

A tapered roller bearing assembly includes a one-piece inner ring that has two outer raceways oriented at angles relative to a longitudinal axis and a first outer ring with a first inner raceway and a second outer ring having a second inner raceway. The bearing assembly includes a spacer ring that has an axial width and is positioned around the inner ring and between the first and outer rings. A plurality of rolling elements is in rolling engagement with the first outer raceway and the first inner raceway. A plurality of rolling elements is in rolling engagement with the second outer raceway and the second inner raceway. The axial width is selectively established to obtain a predetermined axial clearance between the inner ring and the first outer ring and the second outer ring.

A roller bearing assembly for use in a fracking pump crank shaft includes an inner ring being positioned an outer ring and a plurality of rolling elements disposed therebetween. Each of the rolling elements have a bore extending therein. The roller bearing assembly includes a cage having an annular disc with pins extending axially inward therefrom and into the bore. The pins are positioned on the annular disc so that the rolling elements are spaced apart from one another with a gap extending continuously therebetween. The gap is of a predetermined magnitude to maximize the number of rolling elements that fit between the inner ring and the outer ring to maximize load carrying capacity of the roller bearing assembly.

A rotary milking platform 1 has a deck 2, a circular upper beam 4 connected to and supporting the deck, a circular lower beam 6 and a series of carriages 5 connected end to end to form a ring between the beams. The platform is formed such that the upper beam 4 is arranged to rest and rotate on the ring of carriages 5 to rotate the deck 2. Each carriage has at least one carriage roller 10, and each roller 10 arranged to rotate on the lower beam 4. Each roller 10 also has a retention flange 11 at only one side. The flanges 11 of some of the rollers 10 are at or adjacent an inner side of the ring, and the flanges 11 of others of the rollers are at or adjacent an outer side of the ring. The rollers 10 of the ring are arranged such that at least one roller is oriented with its flange 11 on an opposite side to another of the flanged rollers immediately adjacent to it. The flanges prevent the carriages from moving off the lower beam 4 when the platform 1 is in use. Further, at least some of the carriages can be disconnected from the ring and swung laterally to be moved free of the beams 4, 6 for maintenance, repair or replacement.