API casing pipe and johnson well screen tube for geothermal well

Our company is a professional mnufacturer of well screen.my email: info7356@guangxing-screens.com

I'm Joanna sun from hengshui China guangxing screen Co.ltd 

The continuous-slot screen is widely used throughout the world for  water, oil, and gas 

wells, and is the dominant screen type used in the water well industry.  It is made by 

winding rolled wire, triangular in cross section, around a circular array of longitudinal rods.  

The wire is attached to the rods by welding.  Welded screens  are commonly fabricated 

from stainless steel.  

Slot openings are manufactured by spacing successive turns of the outer wire to produce 

the desired slot size.  Slot openings have been designated by numbers which correspond 

to the width of the openings in thousandths of an inch.  A No. 10 slot screen, for example, 

is an opening of 0.010 inch. 

Continuous-slot screens provide more intake area per unit area of screen surface than any 

other type.  This type of screen has maximum open area.  For best well efficiency, the 

percentage of open area in a screen should be the same as, or great than, the average 

porosity of the aquifer material.  Water flows more freely through a screen with a large 

intake area compare to one with limited open area.  The entrance velocity is low, therefore 

head loss for the screen is at a minimum, thus minimizing drawdown in the well.