App Support &
Documentation

SCE (Solids Control Equipment), SRE (Solids Removal Efficiency), LGS (Low Gravity Solids), HGS (High Gravity Solids), MCR (Mud on Cuttings Ratio), and BFR (Base Fluid Ratio).

This app uses US customary oilfield units for volumes: Barrels (bbl) are used for mud and hole volumes. Gallons are used for base fluid additions. Cubic yards are used for cuttings waste volume. Well depth inputs must be in feet.

Not in this version of the app, but an update featuring metric units is in the works.

SRE is the volume of drill solids removed from the active mud system divided by the hole volume drilled. The 'volume of drill solids removed' means those drill solids removed due to mechanical separation efficiency. It excludes drill solids removed because of the mud losses that occur due to solids control equipment operation (e.g., a flooded shaker does not get a higher SRE).

Low Gravity Solids (LGS) are all the solids in a drilling fluid other than weighting agents. The app uses 2.6 specific gravity for LGS as a default. High Gravity Solids (HGS) are commercial mud products (like barite) added to increase the density of the fluid.

The volumetric ratio of mud to cuttings is calculated from densities measured on the well site. The app prompts the user to input suction pit mud weight in units of pounds per gallon (ppg). The app then prompts the user to input cuttings discard density, usually from the shale shakers, in units of pounds per quart. The density difference allows MCR to be accurately calculated provided weighting agents are not being concentrated in the cuttings.

If fine screens (API 170 or finer) are disproportionately stripping weighting agents, the standard Density Method will be inaccurate. You must use the Topped-up Retort procedure included in the app's Advanced Diagnostics folder.

Target LGS is the volume percentage of low gravity solids concentration at which a drilling fluid is maintained. If there is significant variation in LGS solids in the interval drilled, then LGS data must be averaged.

This input can be found on all mud reports. It is the base fluid content of the active mud system. In the case of OBM or synthetic muds, be careful to not use oil/water ratio data for this input. In the case of water-based mud, it is calculated by subtracting the corrected solids and oil concentration from 100%.

MCR varies significantly during the course of drilling a well. MCR is largely a function of particle size, which varies with depth and deviation of the wellbore. The actual MCR data measured in the field will depend on the mud program, drilling area, shaker screen selection, and cuttings drying equipment.