NRIC selected the FE-16673 gauge widening assembly. The Pandrol Fastclip FE system is a resilient, threadless, pre-assembled rail fastening system with low installed cost. The system is a self-tensioned fastening which generates toe load on installation, and was supplied with a 14 mm collar on the field side and 6 mm collar on the gauge side. The components were supplied pre-assembled on to monoblock concrete sleepers produced by sleeper manufacturer ZPSV.
Pandrol partnered with ZPSV in a joint agreement to develop the monoblock sleepers in ZPSV’s factory in Varna. Pandrol supplied the sleeper factory with a camlock-type FE shoulder holding mechanism. This required the conversion of the existing moulds to Pandrol FE. In total 30 sleeper moulds were converted, with each mould incorporating five sleeper cells. Throughout this process, Pandrol engineers were in attendance to ensure the sleeper accuracy and quality was maintained, and all the necessary inspection gauges were designed and supplied.
The finished sleepers were transported by rail from ZPSV, and built into panels at Anton station. The running rails of a redundant secondary line were used as a level bed for alignment of the sleepers. The panels were assembled in lengths of 36 m, with a sleeper spacing of 0.58 m on tight curves. There were either 58 or 62 sleepers per panel depending on the curve radius. Each panel was then stored to a maximum stack height of nine sleepers.
The installation was undertaken by contractor TRACE using a Track Panel Laying machine to lay the panels sequentially. This is a three-stage process: Panel Lifting, Panel Transporting and Panel Laying. This machine was used effectively to lay all 175 pre-assembled panels. During the panel building stage, two Pandrol Rosenqvist CD200 clip driving machines were used, capable of clipping, extracting and sleeper lifting. Pandrol technicians provided full training support for use of the machinery and handtools.
Pandrol also supplied 300 Fastclip FE Vortok Stressing Rollers, introducing a new design that gives adjustability and is capable of working on gauge widening assemblies.