High Gravity Solids
Definition - What does High Gravity Solids mean?
High Gravity Solids are types of drilling fluid solids which have a higher density. The density of such type of drilling fluid is higher or equal to the density of hematite or barite that is used to weigh up the drilling fluid. High gravity solids are at times also referred to as weighing materials. A drilling fluid usually contains drill solids as well as bentonite clay.
Petropedia explains High Gravity Solids
The solid content is usually a fraction of the total density in drilling mud, and it always increases while drilling because of cuttings, mud chemical additives and weighting material. The solid content usually refers to the soluble and insoluble solid content in the drilling fluid system. The concentration of high gravity solids in drilling fluids is calculated by mud engineers on the basis of analyzing the drilling mud, mud weight, retort analysis, chloride titrations and other types of information. The solids are reported as pounds per barrel or volume percentage. The concentration of water and hematite is usually 1.0, barite 4.20 and 5.505 gram per cubic centimeter respectively. Hematite is a more dense material, with minimum specific gravity of 5.05 g/cm3 per API and ISO specifications. Calcium carbonate which has a specific gravity of 2.7 to 2.8 is considered as a weighting material but is used more for its acid solubility than for density. Siderite which has a specific gravity of around 3.8 is used to make mud denser, but can cause problems by dissolving into the mud at high pH. Ilmenite which has a specific gravity of 4.6 is used in drilling fluid and cement. Only barite and hematite have API/ISO standards.