A new physical testing and labeling procedure for shaker screens. To be API RP 13C compliant, a screen must be tested and labeled in accordance with the new recommended practice. Two tests were devised: cut point and conductance. The tests describe a screen without predicting its performance and can be performed anywhere in the world. [...]
a. RP13C provides an unequivocal procedure and benchmark for comparing different screens. b. The primary intent of RP13C is to provide a standard measuring system for screens
Should I screen with a finer screen now if what used to be called a ‘200 mesh’ screen is now labeled API 120?
Users are advised to determine the screens that work best in their applications regardless of what the new API Screen Number happens to be.
Although some companies are changing their part numbers to reflect their conformance to RP13C, others are not. It is therefore best to specify the RP13C value you want.
a. The biggest variation is due to the shift from using D50 to D100. b. The previous test procedure (RP13E) measured the distribution of the apertures in the screen.RP13C uses a physical and repeatable test using actual solids (dry aluminum oxide) which measures the coarsest particle that can pass through the screen.
By definition, every particle of the D100 size or coarser will be discarded. b. In practice some portion of solids finer than 172µ may be removed.
The API Screen Number is a single number which defines solids separation potential under specific test conditions. It does NOT define how a screen will operate on a shaker in the field as this will depend upon several other parameters such as fluid type & properties, shaker design, operating parameters, ROP, bit type, etc.
The API Screen Number corresponds to the API defined range of sizes into which the D100 value falls.
a. The D100 cut point of a screen is the particle size at which no particles will pass through the screen. b. D100 is a single number determined from a prescribed laboratory procedure – the results of the procedure should yield the same value for any given screen. c. The D100 should not be compared [...]