Before using the product, we usually need to check it, and mining tunnel anchor rods also need to be checked before use. Let's learn together.
Check the orientation of the positioning grout stop and limit rings for mining roadway anchor rods. If damaged, replace them according to technical requirements; Check the orientation and smoothness of the exhaust pipe; The anchor cable is inserted into the hole, and when the positioning grout stop ring reaches the hole opening, the pushing is stopped, and the grouting pipe and one-way valve are installed; After the anchor cable is in place, check again whether the exhaust pipe is unobstructed. If it is not unobstructed, pull out the anchor cable, troubleshoot, and then send the cable from the beginning.
At the same time, the temperature value of the buried point can be synchronously measured. After the strong anchor rod head is in place at the hole opening, the cement paper blocking the hole opening can be lifted, and the rod body can be quickly inserted and installed in place. If there is no overflow of cement mortar at the orifice, it indicates insufficient injection of mortar. The rod should be pulled out and poured from the beginning before installing the anchor rod; The degree of penetration of the anchor rod into the hole should not be less than the design specifications.
The fullness of anchor bolts in mining tunnels is the key to ensuring installation quality. The process requires the grouting pipe to be inserted 5-10 cm away from the bottom of the hole and slowly and uniformly pulled out with the injection of mortar, in order to prevent the detachment of mortar inside the hole caused by too fast pipe pulling. When the mortar is insufficient, it should be re injected. This is all to ensure that the full length of the anchor rod is wrapped in sufficient mortar to ensure its anchoring effect.
When there is a stress change inside the tested structure, the mining tunnel anchor rod will be stretched or compressed, and the steel sleeve will deform synchronously. The deformation makes the equal strength anchor rod stress gauge feel the deformation of tension or compression, and the deformation is transmitted to the vibrating string to transform into a change in the vibrating string stress, and then the oscillation frequency of the vibrating string is changed.
The electromagnetic coil excites the vibrating string and measures its oscillation frequency. The frequency signal is transmitted through a cable to the reading device to measure the stress on the steel bars inside the tested structure.