Maintenance of impact testing machine

Maintenance of impact testing machine

The impact test machine is a very important test project in mechanical performance testing. During use, we need to maintain and pay attention to the equipment.

1. Things to note

Installation and foundation of the test machine. The impact tester must be firmly installed on a concrete foundation with a sufficiently large mass to ensure that the foundation mass is no less than 40 times the mass of the pendulum, and ensure that the tester and the earth are a whole. Note that the 4 anchor screws cannot be loose at all.

(2) Use the centering sample and caliper to verify the center of the pendulum impact knife overlap with the center of the anvil span. The method is as follows: stick the V-shaped notch test paper, place the sample between the anvils and align, and tap the sample with a pendulum to hit the blade to detect the distance between the center line of the impact blade mark on the sample and the top of the V-shaped notch. Note that the impact blade is at the center of the span of the support, the tolerance is 0.5mm, and the span of the anvil is 40.0o+0.2mm.

(3) The pendulum air strike is returned to zero by visual inspection. The allowable value of the return-to-zero difference is ±0.1% of the pendulum energy.

(4) Energy loss (pointer friction, bearing friction and air resistance) should meet the requirements of energy loss in Table 1.

2. Working process of impact testing machine

The impact tester uses the potential energy of the pendulum to impact the sample at one time. , when in the pre-reclining position, release the pendulum and impact the sample at a certain speed (5∽5.5m/s), because the results are different for different impact velocities. Only when the impact energy during the impact sample is completely absorbed by the sample and not by other parts, the impact test data will be accurate and reliable. For this purpose, the premise is that the test machine must have sufficient rigidity and all parts associated with the sample should be consistent with the relevant technical conditions.