Abstract
Since 2003 Ukrainian railways have used KPP-5 intermediate elastic fastenings. These fastenings unlike their predecessors (for example, terminal-bolted fastenings (KB) widely used on railways), first of all, have fewer elements. The KPP-5 fastening does not include screw joints, which considerably increases the pressing force between rail and tie, and resistance to track displacement forces. This may lead to reduction of the total labour input for routine track maintenance due to cutback of track works needed for mounting terminal and insert bolts. The article deals with forecasting the operational life of PRP 3.2 (9mm depth) and PRP 3.2.1 pads (10mm depth). In engineering the operational life is a time interval (for the railway track – tonnage passed) during which the element fulfils its functions. One of the main reasons why the assembly unit KPP-5 fails is low pressing forces between rail and tie. It occurs due to many processes; among the basic ones is the changed characteristic of underrail pads. And the application of new types of pads – PRP 3.2 (9mm) and PRP 3.2.1. (10mm) may solve this problem.
Highlights
The article deals with forecasting the operational life of PRP 3.2 (9mm depth) and PRP 3.2.1 pads (10mm depth)
It occurs due to many processes; among the basic ones is the changed characteristic of underrail pads
The KPP-5 intermediate elastic fastenings have been applied on Ukrainian railways since 2003
Summary
The KPP-5 intermediate elastic fastenings have been applied on Ukrainian railways since 2003. For continuous welded rails one of the main problems for intermediate fastenings is to create sufficient per-unit length resistance, i.e to provide the pressing force between rail and tie more than 23 kN. The mounting of the assembly unit KPP-5 provokes initial vertical deformation of the spring terminal. Under the terminal pressure 2 Qtienrimt the underrail pad shrinks and creates the elastic (spring) resistance. Equilibrium of forces in the assembly unit occurs when the mounting forces of terminal pressure equal the elastic resistance of the pad Qmount u stat pad. As the structural peculiarity of the fastening KPP-5 is the equilibrium of the deformations of the pad and the inverse deformation of the terminal, the mounting pressing of the terminal can be presented as mount init. Considering expression (2), the mounting pressing on the pad can be defined as
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
