How to fasten railroad screw spikes to railway sleepers
During the time when you are enjoying your vacation, listening the voice of the moving rail wheels, the railroad screw spikes
are under the huge pressure of vertical force, horizontal and longitudinal force. The railroad spikes play an important role in ensuring the safety of the railway transportation. In order to make more use of the railroad spike, it is very strict for the workers to ensure the pull-out force of each screw spike more than 60KN ( 6 tons ). Here are the mainly processes of fastening and maintenance of railroad spikes.
First, add the 130kg of sand to the anchoring pot from the inlet point and then heated to about 110℃. Next, together with 50kg of cement, the sand will be heated to about 130℃. Finally, about 100kg of sulfur and 2kg of paraffin were added after mixing. Then mix and heat the anchor material. What’s more, the mainly features of the anchor materials include melting in 80℃, most rare in 130~140℃, thickening in 160~180℃, burning in 220℃.
When the temperature rises up to about 170℃, the mixture changes from liquid state to jelly. At this time, the grout will be added in the pot and the temperature should be maintained at about 160℃.
Then put the mixture into the bucket.
Spoon the mixture equably into the screw spike hole and keep a distance about 10mm to the top of the screw spike hole.
Nailing: Handle the screw spikes, then nailing the screw spike into the center of the hole through slowly rotating.
The screw spike should be perpendicular to the surface of the rail ditch and the gradient should be limited into less than 2°. Besides, the crossing of the rail ditch and the midline of the railroad spike, shouldn’t deviate the center of the hole for more than 2mm. what’s more, the round-table of the spike should be higher than the surface of the rail ditch, but the height should be limited less than 2mm.
Repair of the railroad nail holes’ surface:
In order to keep the cleanliness of the railway sleepers, a flat shovel should be used to wipe out the mixture outside of the screw spike holes. And the extra mixture can be recycled in the pot to another use.
Painting the anti-corrosion paint in the root of the railway bolts and the anti-corrosion paint should be painted uniformly.
According to the construction supervision, the quality of cement mortar must pass the sample inspection. The compressive strength and tensile strength should be less than the predetermined value. And the pull-out force of each screw spike must be less than 60KN. During the construction, the compressive strength should be tested after fastening 1000 or 1500 railway sleepers and the pull-out force will be tested after fastening about 2000 or 4000 railway sleepers.
According to the provision, after the above processes, every rail screw spike must accept the examination of pull-out force and parallel force.
For example, the pull-out force of this screw spike reaches 95KN and meets the requirement that the pull-out force shouldn’t be less than 60KN.