1. What is the D100 and how is it related to the API screen designation?
The D100 value represents the diameter of the coarsest particle (in microns) which will pass through the screen during a dry laboratory test and is a single number, not a range of sizes.The API screen designation for a screen is the API-defined range of sizes into which the D100 value falls. Some of the coarser size classes span quite a large range of D100 values.
2. What does/doesn’t the D100 tell us?
The D100 value is the finest particle diameter at which the screen no longer sends 100% of the particles to the discard stream. This is also the coarsest particle that will pass through the screen.
The D50 value is the particle size at which the screen sends 50% of the particles to the “overs” (discard), while the remaining 50% report to the “unders” (undersized stream) and the D100 should not be compared in any way. The D50 was interpreted as the micron size where a screen makesa 50/50 split.
The API RP 13C D100 is a very specific value determined from a carefully-controlled laboratory procedure so that any laboratory should measure the same value for any given screen cloth.
3. Will a screen with a D100 of 110 microns remove solids finer than 110 microns?
Yes, more than half of the particles that are coarser than D50 and finer than D100 will report to the overs. A significant portion of the particles finer than D50 will also report to the unders. (By definition, every particle classified in the D100 size or coarser will report to the overs as expected.)