Built in 1923, the Ukraine’s Olympic Stadiumin Kiev has been renovated on several occasions but is currently undergoing a thorough, comprehensive modernisation programme in preparation for the UEFA Euro 2012 football tournament. Co-hosted by Poland and the Ukraine, tournament matches are scheduledto take place in various cities in both host nations. The Final will be staged in Kiev’s Olympic Stadium on 1st July 2012.
Since 2008, Kiev has therefore been a hive of construction activity. The Olympic Stadium itself will need to accommodate more than 83,000 spectators for the Finals. At the core of this modernisation programme is a new retractable, translucent stadium roof, as well as integrated flood lighting systems.
The roof of the Olympic Stadium is spanned with ropes, whose coupling points comprise load-free bearing supports. All rope coupling points at the edge of the roof and on the masts are accommodated by a total of 240 spherical plain bearings, which are lined with Elgoglide sliding low friction layer. The bearings are dimensioned in such a way that they can easily support the loads from the roof acting on the bearing positions.
A total of 80 radial spherical plain bearings of type GE160UK-2RS-W3 support the base plates of the roof columns. The maintenance-free bearings have a 160mm diameter bore, are sealed on both sides and have a corrosion-resistant steel inner ring.
Arranged in pairs, a further 160 radial spherical plain bearings of type GE140UK-2RS-W8 support the loads from the roof structure itself. These bearings have a 140mm diameter bore and are sealed on both sides. The bearings also have a special inner ring bore that is lined with Elgoglide, enabling the bearings to be mounted more easily in the application. In addition, the bearings are designed to compensate for any temperature-related (longitudinal) axial expansion.
Elgoglide is a highly wear-resistant sliding layer made from PTFE fabric, which is embedded in synthetic resin and bonded to the outer or inner ring bore. This low friction, sliding material neither expands when exposed to humidity, nor heat-seals with metal. It is also resistant to most chemical agents and is ideal for use in rotary and linear motion applications.
The material accommodates loads, transmits them and also replaces the lubrication function. Relubrication of Elgoglide bearings is therefore not required. In fact, relubrication of the bearings would destroy the carefully matched tribological system. Elgoglide bearings offer high load carrying capacity and long service life, combined with small installation space and low friction and provide a number of advantages inapplications that are characterised by high loads and small swivel angles. Maintenance free bearings also minimise downtime and service costs, whilst eliminating the need and cost of lubricants.