Views: 0 Author: Site Editor Publish Time: 2022-07-19 Origin: Site
The wheel trencher bits mud bag refers to the phenomenon that the surface of the drill bit is covered by the mud mass so that the drill bit cannot perform normal rock breaking, which may occur during normal drilling and tripping. So what are the precautions for the wheel trencher bit mud bag? Let's take a look at it next.
Here is the content list:
l Adjust drilling fluid performance
l Engineering technical measures
l Reasonable choice of drill
l Other measures
The performance of the drilling fluid is a very important factor affecting the mud bag of the wheel trencher bits. Therefore, in the good section prone to mud bags, the mud bag phenomenon can be prevented by adjusting the performance of the drilling fluid. By controlling the density and water loss of the drilling fluid, the quality of the mud cake can be improved; by adding inhibitors to improve the inhibition of the drilling fluid, the hydration, and decomposition of the mud shale can be effectively controlled; the solid phase content in the drilling fluid needs to be controlled to reduce. The viscosity and shear force of the drilling fluid can be removed in time, and the harmful solid phase can be removed in time; a certain amount of lubricants, surfactants, and detergents are added to the drilling fluid to improve the lubricity of the drilling fluid, which can effectively protect the Chain trencher bit and reduce the surface damage of the drill bit. The adsorption capacity of drilling cuttings; in addition, alkaline substances should be added to the drilling fluid in advance before entering the gypsum formation to prevent it from contaminating the drilling fluid; for sandstone layers with strong permeability, shielding temporary plugging materials can be added to the drilling fluid to reduce Permeability leakage.
Under the conditions allowed by the equipment, the mud-packed well section should be drilled with a large displacement as much as possible to ensure effective flushing of the bottom hole and the drill bit, and to carry out the cuttings in the wellbore in time to prevent the formation of virtual thick mud cakes; In soft mudstone formations, low WOB and high rotational speed should be used, and drillers are required to the operation is fine, and the drilling is carried out evenly. Before entering the wheel trencher bit, a series of measures can be taken to prevent the mud bag of the drill bit: sufficient circulation should be carried out to prevent the hydration and decomposition of the remaining cuttings in the well; The mud cake on the good wall is scratched and squeezed. When the short tripping effect is not good, the roller cone bit can be used to pass through the well first; butter can be applied to the drill bit and the centralizer in advance to form a protective film on the surface. During the drilling process of the long open-hole section, it is necessary to carry out halfway circulation, and the mud cake accumulated on the drill bit should be washed away before continuing the drilling; when the drilling encounters resistance, the pressure cannot be blindly lowered, and the pump must be turned on to establish circulation; the drilling to the bottom of the well It is also necessary to turn on the pump for circulation first, and use a large displacement to fully clean the drill bit and the bottom of the well.
When the side angle of the wheel trencher bit cutting teeth is large, a lateral thrust is generated on the cuttings during the drilling process, which makes them move to the outside of the bit, which is conducive to the discharge of cuttings and prevents the bit from generating mud bags. The position, size, shape, and angle of the water hole have a very important influence on the hydraulic cleaning effect of the drill bit, and its design should be conducive to the discharge of cuttings; in the mud-bag-prone section, a blade-type wheel trencher bit should be selected, and its chip removal. The groove is deep and wide, the overflow volume is large, and the hydraulic cleaning effect is good.
Drill bit mud bagging can also be prevented by preparing a functional coating on the surface of the wheel trencher bit. The commonly used coatings are mainly divided into two types: one is the coating that prevents the mud bag by generating a tiny negative potential on the surface of the drill bit to inhibit the adsorption of negatively charged drill cuttings to the surface of the Chain trencher bit, mainly including nickel-plated coatings, epoxy coating, and surface nitriding, etc; another coating reduces the adsorption of drill cuttings by the drill bit by reducing the surface energy, thereby preventing the generation of mud bags, mainly including strengthening Teflon and other fluoropolymer coatings.
The above is the relevant content about the preventive measures of wheel trencher bit mud bag, if you are concerned about wheel trencher bits, Chain trencher bit, cup cutter teeth for vemeer, you can contact us, our website is www.cuttingpicks.com.
