The construction party engaged in the geological exploration industry or contracted drilling project, after the completion of drilling, will always design to calculate the hole depth, settlement of project costs, then here, to share with you the calculation method and insights of the hole depth, the following several concepts:

1, the definition of drilling depth: starting from the hole, the drill pipe and the length of the drill tool in the hole are all added together, and the sum is the drilling depth.

2, the definition of machine height: on the rig, due to the active drill pipe, a drill pipe after the completion of drilling to reach this height, you need to connect another drill pipe and continue drilling, then the distance between this position to the hole is the machine height.

3, the definition of the machine size: the machine size refers to the length above the machine height after a drill pipe drilling to a certain extent.

Simply put, the drill pipe involved in drilling can be divided into several parts in the drilling hole. Part of the drill pipe is buried in the hole, and the length of the hole buried in the hole is the hole depth. Part of the drill pipe length is higher than the hole, this part of the length includes machine height and machine allowance. For single-hole drill pipe, hole depth + machine height + machine size = total length of drill pipe.

In order to be responsible for the geological report and Party A, the drilling construction party must not cheat, some inexperienced or novice core appraisers should also pay special attention to this problem, when the core adoption rate is insufficient, it should be reported in time, not artificially elongated. In general, when the rock structure is relatively complete, it is possible to judge whether there is fraud from the drill core.

After the drill hole is swept to the bottom, the hole is marked with paint, the drill pipe is pulled out, and the length of each drill pipe placed on the drill tower is measured from the top to the bottom with a tape measure or steel tape measure, record and add. The total length of the drilling tool from the hole marking to the end of the last drill pipe should be the hole depth, and the error should not exceed one percent.

Here to share my personal opinion, regardless of the length of the outer pipe system of the drill pipe, the length of the core is 1.5 meters, so when calculating the hole depth, the hole depth = the number of drill pipe buried in the hole × the length of drill pipe - the remaining length of the last drill pipe in the hole outside the hole + the length of one drill pipe. That's the length of the actual core.