The fatigue test or rail clip
Scope of application:This standard is applicable to fatigue test of SKL14 Rail Clip,Elastic Rail Clip,Type III rail clip and Deenic rail clip.
Test principle:The fatigue test is carried out by applying impulse load to the clip bar in the way of displacement control.
1. Displacement controlled fatigue testing machine or electro-hydraulic servo fatigue testing machine are adopted for rail clip fatigue test.
2. The loading frequency of the test machine is (4-16)Hz.
1. The real sample of elastic strip shall be randomly selected;6 pieces of spring bars of each type were selected, 3 of which were spare samples.
2. The physical sample of elastic strip shall conform to the relevant provisions of product standards.
1. Place the test strip on the measuring platform and measure the relative elevation of the front end of the middle section of the strip with a dial gauge. The reading accuracy is 0.01mm, denoted as Ho;
2, according to the standard assembly of the bullet bar, the bullet bar with the part embedded in the hard metal embedded block of the arc;
3. When the loading head of the fatigue testing machine is in contact with the standard loading beam, the loading head continues to move downward relative to the substrate of the loading device until the displacement reaches the specified design and assembly displacement d of the spring bar;
4. On the basis of displacement 3, the dynamic displacement +0.50~ 0.90 mm is continued to be applied, that is, in the fatigue test process of the spring bar, the displacement of the buckle end of the spring bar is d+0.5d_o.9~.
5, loading cycles is 5 * 10 ^ 6.
Maximum static test force 50kN
The accuracy of the whole range is not divided 0.5%;
Maximum dynamic test force 40kN
The precision of indication shall not be greater than 0.5%.
The maximum amplitude of the actuator is 75mm
Frequency range: 0.01 -- 50Hz
Displacement measurement resolution: 0.01mm (magnetostrictive displacement sensor)
Maximum test space 0-500mm (manual adjustment)
The distance between the columns is 600mm
The number of stations is 1