WorldWide Drilling Resource

14 JULY 2022 WorldWide Drilling Resource® The Role of Reamers Adapted from Information by JB Trenchless Reaming is distinct from boring, as the tasks and methods for completion are entirely different in both processes. Boring is the process of creating a hole in a surface and using that space to lay specific pipelines; reamers are put into use after the hole has been bored. A reamer is tasked with making the existing hole larger to accommodate the installation of new pipelines. This has made horizontal directional drilling (HDD) rock reamers an integral portion of most underground drilling projects. It is also why reamers are known as hole openers. Many trenchless projects occur in areas with a significant distribution of soil, so there is a substantial risk of the hole collapsing during wide boring jobs. To prevent this danger, workers are usually assigned to remove the dirt on a gradual level, which enables them to stabilize the hole and use a reamer. The most important use of HDD rock reamers comes in pipe replacement projects. In these projects, reaming becomes an absolute necessity because rather than creating a new hole in the soil, the purpose is to increase the size of the hole while placing a new pipe. In most projects today, the existing pipe is removed through a breakdown process conducted by a pipe reamer attached to an HDD machine. This enables a new pipeline to easily slide into place, allowing workers to remove the previous pipes and broken rubble at the exit point. There are three primary types of reamers on the market. They are: Compaction Reamers: These types of reamers are often used in areas where there is soft soil which has a high chance of collapsing in on itself. Compaction reamers rely on the action of forcing drilling fluid into soil surrounding the hole. This is done through a bentonite filter cake. The filter cake essentially forces or injects drilling fluid into the surrounding soil, providing a level of support which prevents collapse. Hole Openers: Hole openers are reamers that make existing holes larger and allow individuals to replace or install additional pieces into the hole. Hole openers use rolling cutters for reaming in rock formations. They are also known as HDD rock reamers because they are consistently used in HDD operations. Mixing Reamers: In harder ground conditions, or when trying to ream a borehole in ground predominantly made of clay, one needs to employ mixing reamers. These reamers have a variety of threads which include flag cutters and rippers. When activated, these rippers can easily break down soil and displace cuttings from the hole. They require special drilling fluid additives, making them an inadvisable substitute for HDD rock reamers. Courtesy of Bit Brokers International. DIR Booth 1812