Non-excavation mud formula suitable for cobble clay composite stratum

Abstract

The invention provides a non-excavation mud formula suitable for a cobble clay composite stratum. The non-excavation mud formula is prepared from the following raw materials including, by mass, 100 parts of water, 4-6 parts of disperse film forming agents, 0.1-0.2 part of a filtrate reducer, 0.2-0.4 part of a viscosity improving agent, 1-2 parts of lubricating drag reduction agents and 0.4-0.6 part of a water-sensitive inhibiting agent. The non-excavation mud formula suitable for the cobble clay composite stratum has the good rheological property, in the non-excavation drilling process, the viscosity of mud is low, the drilling resistance is small, the rock carrying effect is good, when the non-excavation construction is suspended, a space net-shaped structure with certain strength can beformed by the mud, and instability and collapse of hole walls are prevented.

Description

technical field [0001] The invention relates to the technical field of non-excavation mud, in particular to a non-excavation mud formula suitable for pebble-clay composite formations and a preparation method thereof Background technique [0002] Pebble and gravel formations are relatively common in my country, and they are generally found in shallow layers, which is a relatively common complex formation. When non-excavation construction is carried out in broken strata such as sandy soil layers and pebble gravel layers, because there is almost no cohesion between pebble particles, the strength of the stratum is low, and the hole walls are prone to instability and collapse during the excavation process, making it extremely difficult to form holes. When the gravel particles are filled with cement, the pebble formation has a certain cementation strength, but the cement is generally a water-sensitive mineral, which is easy to swell when it absorbs water, and the conventional non-...

AI Technical Summary

Problems solved by technology

When non-excavation construction is carried out in broken strata such as sandy soil layer and pebble gravel layer, because there is almost no cohesion between pebble particles, the strength of the stratum is low, and the hole wall is prone to instability and collapse during the excavation process, making it extremely difficult to form a hole

When the gravel particles are filled with cement, the pebble formation has a certain cementation strength, but the cement is generally a water-sensitive mineral, which is easy to swell when it absorbs water, and the conventional non-excavation mud has no inhibitory effect, causing the cement to absorb water and swell to damage the formation Stability destabilizes the hole wall

And in the non-excavation construction in the pebble gravel formation, due to the high hardness of the pebble gravel, the footage efficiency is low, and the drill bit is generally worn during the drilling process.

[0003] When the pebble gravel stratum is combined with the clay stratum, in addition to the hole wall collapsing easily due to the too small bearing capacity of the pebble gravel layer, the clay is easy to adhere to the drill bit and cause the mud bag bit. The cutting edge of the drill bit is wrapped by clay, and the Unable to cut the formation so that the drill cannot be drilled

Clay adheres to the drill pipe, increasing the frictional resistance of the drilling tool, causing the pipe to not be dragged

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