Innovation

With our individual technological solutions, we pursue the goal of supporting our customers' product leadership. Our focus of innovation is on energy efficiency as well as increasing the precision and comfort of our customers' products.

However, the innovative ability of Brutscher Maschinenbau is not limited to product and technology developments, but is rooted in all areas of the company.

We are convinced that we can further strengthen our innovative strength by thinking outside the box. That is why we not only trust the knowledge and wealth of experience of our teams, but also work closely with external partners, research institutes or start-ups.

Patented tilt segment bearing development at Brutscher Maschinenbau

Radial tilt segment bearings are used to support high-speed shafts and rotors in turbines, gearboxes, compressors, generators, turbochargers and electrical machines. Constantly increasing power densities in mechanical engineering place increasing demands on the performance and operational safety of modern, hydrodynamic radial tilting segment bearings. Decisive parameters are the resulting bearing temperature during operation and the amount of lubricating oil required for the radial tilting segment bearing.

On the basis of currently customary radial tilting segment bearings, Brutscher Maschinenbau GmbH has developed an oil management system that is integrated into the bearing and that regulates the incoming cold lubricating oil and the discharged warm lubricating oil separately.

The result is a plain bearing system with an exceptional level of performance and development potential. In test runs, the amount of oil was reduced by over 50% compared to the bearings currently used by the market partner.

The BM oil control system

With the BM oil control system:

cold lubricating oil is supplied to the bearing across the entire tipping segment width
the mixing of cold / warm lubricating oil is avoided
the warm oil transfer from segment to segment is minimized
flow losses are reduced

and thus the temperature level, the efficiency and ultimately the operational safety are improved compared to conventional radial tilt segment bearings.

Function of hydrodynamic radial tilt segment bearing

The function of a hydrodynamic radial tilting segment bearing is based on the interaction of:

the geometric dependence between the shaft diameter and the radius of curvature of the radial tilt segments
the rotation of the shaft
the supplied lubricating oil

This creates a lubricating gap, which reduces the friction between the shaft and the bearing and dissipates the heat that is generated.

The radial tilt segments (usually 4 or 5 pieces) are inserted in the circumferential direction in the bearing body and positioned using a retaining screw. In terms of design, a space is provided between the segments, which is used in most radial tilt segment bearings for the supply and removal of lubricating oil.

Lubricating oil supply for a conventional radial tilting segment bearing

Conventional radial tilting segment bearings guide the lubricating oil into the space between two segments using oil nozzles. Due to the lack of spatial separation of the lubricating oil supply and the lubricating oil discharge, mixing of the incoming, cold lubricating oil with the discharging, warm lubricating oil cannot be prevented. A warmer lubricating oil is thus effectively supplied to the bearing.

The resulting higher bearing temperature has a direct impact on the efficiency or the power loss of the radial tilting segment bearing and can have undesirable effects on operational safety.

Lube oil supply with the BM oil control system

The BM oil guide system integrated in the radial tilting segment bearing is not to be regarded as a single component, but is made up of the components of the bearing body, oil guide strip and oil guide cover. The central component of the BM oil control system is the oil control strip, which is positioned in the space between two tilting segments and separates the incoming, cold lubricating oil from the outgoing, warm lubricating oil.

The cold lubricating oil is conveyed through the bearing body into the oil guide, from which the lubricating oil is sprayed into the segment engagement by means of one or more holes. The oil guide bar is designed as an oil chamber in the area in front of the tilting segment engagement, which, in addition to direct injection through the bores, ensures that the incoming, cold lubricating oil is distributed over the entire width of the segment engagement.

The supplied lubricating oil is conveyed between the shaft and the tilting segment in the direction of rotation to the end of the tilting segment and heated by the friction. At the end of the tilting segment, the warm lubricating oil that runs off is guided radially away from the shaft into the oil drain shaft by centrifugal force. The cutting-shaped oil drain shaft - made contactless to the shaft - and the existing cross-sections support efficient and turbulence-free drainage of the lubricating oil.

The targeted oil routing in the oil drain shaft prevents additional heating of the tilting segment due to the lubricating oil running off. The shape and cross-section of the oil drain shaft in the oil guide rail are consistently continued in the bearing base. The running, warm lubricating oil is then led out of the radial tilting segment bearing via the oil guide cover.

The advantages of the BM oil control system compared to conventional bearings

Spatial separation of lubricating oil supply and lubricating oil removal prevents the mixing of warm and cold lubricating oil => optimal utilization of the supplied, cold lubricating oil for the lubrication and cooling of the bearing.
Targeted supply of lubricating oil across the entire radial tipping segment width.
The oil requirement of the radial tilting segment bearing can be reduced by the targeted and effective supply of the cold lubricating oil.
Warm oil transfer from segment to segment is minimized by the geometric design of the oil drain shaft.
Efficient, turbulence-free lubrication oil removal with enlarged cross-sections and volumes. In comparison to a conventional radial tilt segment bearing, the example of a ø70 bearing gives an advantage of
- 50% more available volume in the warehouse for the running, warm lubricating oil
- 300% more cross-sectional area to the side oil guide covers
- 150% more cross-section of the drain opening in the side oil guide covers
Reducing the number of components required (4 components per segment => 20 components per radial tilting cement bearing) means less effort in assembly and service work
Tool-free assembly / disassembly of the radial tilt segments after removing a side oil guide cover
Design of the side oil guide covers enables a more compact shaft design and offers improved design options with regard to low-notch shaft transitions.