3M™ glass bubbles are engineered hollow glass spheres that can be used as a density reducing additive in down-hole applications such as drilling, completion and/or maintenance of a well to reduce and control bottom-hole pressure, enabling at balance, near balance or under balance conditions. A reduced-density control fluid made with 3M™ glass bubbles is ideal for use in depleted reservoirs, as well as geologically-fractured, poorly-consolidated and/or highly permeable formations, where the reduction of differential pressure can result in reduction or elimination of fluid loss/lost circulation, formation damage and differential sticking.
To achieve at balance, near balance or under balance conditions, a control fluid’s weight (or density) needs to be carefully adjusted. 3M™ glass bubbles may be used to reduce weight; significantly or just slightly. As an engineered material, not only do they have the highest strength-to-weight ratio they also have a density that is precise and consistent, making them ideal for fine tuning a control fluid’s weight. 3M™ Glass Bubbles successfully and predictably reduce the density of any control fluid, including drilling, completion and work over fluids, as well as spacers and cement slurries, offering the potential to reduce costs and improve performance.
A reduced-density control fluid made with 3M™ glass bubbles is an effective and economical alternative solution to aerated drilling fluids. It is homogeneous, incompressible, and stable. In spite of the benefits gained by overcoming overbalance conditions, several concerns exist with aerated fluids*; for instance aerated fluids are compressible, require complex hydraulic calculations, generate drill string vibration and signal attenuation while drilling, as well as increase the overall cost because of the need for specialized resources.
(*) Source: Maurer, W. et al (2001) Development and Testing of Underbalanced Drilling Products, DOE Contract No. DE-AC21-94MC31197
Read about field applications for 3M™ Glass Bubbles