N/S | PROBLEM | CAUSE | SOLUTION |
a | Off-spec end product: too many oversize particles | Screen opening too large | Select a screen with a smaller opening. |
Hole or tear in screen | Replace shale shaker screen. | ||
Material bypass | Check seals and gaskets Use a pretensioned screen. |
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b | Off-spec end product: too many fines | Screen opening too small | Select a screen with a larger opening. |
Severely blinded screen | See “Screen blinding” problem below | ||
Screen overloaded | Reduce feed rate. | ||
c | Low product yield from a multiple-deck screener | Upper screen blinded | See “Screen blinding” problem below |
Upper screen opening too small
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Select an upper screen with a larger opening. | ||
Lower screen failed | Check lower screen for holes or tears | ||
Lower screen opening too large | Select a lower screen with a smaller opening. | ||
d | Screen blinding | Wire diameter too heavy | Select a screen with a lighter wire diameter. |
Worn sliders or balls | Check antiblinding devices and replace them as needed. | ||
Screen blocked with material | Clean or replace screen. | ||
Screen overloaded | Reduce feedrate. | ||
e | Short screen life | Wire diameter too light | Select a screen with a bigger wire diameter. |
Improper handling | Be careful not to crease or dent screens during handling or installation. | ||
Screen overloaded | Reduce feedrate. | ||
Screen corroded | Instead of stainless steel wire mesh, try alternative alloys or use a screen made of a synthetic material. | ||
Screen blinding occurs when some or all of the screen’s open area is blocked by mud. This may be caused by a too-high feedrate that solids onto the screen faster than the screen can operate. Or it might be caused by poor screen selection for example, choosing a screen with too heavy a wire diameter. Or it might be caused by your mud’s characteristics, such as cohesiveness. Blinding is often behind a gradual degradation in your shale shaker performance. |