Well Screen & Casing

Doerr bridge slot well screen and casing are made in America and delivered
directly from our factory to your job site.  Doerr's MAX-FLOW and GRAVEL-
GUARD bridge slot well screen represents what well screen was meant to be
for any soil condition.

Doerr's bridge slot well screen is more efficient than saw slotted pipe, less
expensive than stainless steel wire wrapped screen and tolerates handling
abuse and UV exposure significantly better than PVC pipe.

Materials:  Choose from Mild Steel, Galvanized Mild Steel and Stainless          
                   Steel.

Slot Size Selection:  Slot openings are available from 0.03 (.76mm) to            
                                   .185 (4.7mm).

Area Opening Percentage:  The filtering area openings range from 2.8%      
                                                 to 25% depending upon the slot size you
                                               select.  

Wall Thickness:  Four standard material thicknesses are available from
                           stock (10 gauge, 7 gauge, .219 and .250 inch).

Length Selection:  All well screen and casing can be manufactured in             
                                continuous lengths from 4 feet (1.2mm) to 40 feet              
                                (12.2mm) in increments of 4 feet.

Diameter Selection:  All well screen and casing is available in 12 popular       
                                    diameter sizes standard to the water well industry           
                                    (8.625 inches /.219m to 48 inches /14.6m).  For             
                                    larger diameters contact customer service.

Customer Service:  All well screen and casing is manufactured to your
                                exact specifications ensuring an optimum producing
                                water well every time and on time.

Sales Assistance:  For more information regarding these products, contact
                              us for the name of the Authorized Doerr Dealer                   
                               nearest your location.



Doerr Bridge-Slot Well Screen Features
Die Formed Slots               Uniform Slot Size               Vertical Bridge Slots
Reusable                           Sized Joints At No Cost      Fast Delivery
High Collapse Strength      Customized Options          Clog Resistant Design

G-90 Galvanized Protection on Gravel-Guard
Steel water well screen has been known to perform over 50 years under
normal conditions.  However, certain soil conditions require extra protection.  
The American Galvanizer's Association recommends a G-90 finish for 12
years of additional corrosion protection.  This is what you get with Doerr's
G-90 Gravel-Guard Bridge-Slot Well Screen.  Gravel-Guard Galvanized Well
Screen will lasts longer than mild steel and is 75% less cost when compared to
stainless steel.

What's Different About Doerr's Screen Design?
We set out to reduce the size of each opening while still producing a lot of total
open area.  Instead of relying on punched holes, we built a well screen with
one continuous row of perforated bridge-slots encircling the circumference
and running the full length of the casing screen.  The carefully sized slots are
much narrower than any possible punched hole, so even fine-grained sand
can be kept out of the water well.

The amount of open area this bridge-slot design makes possible is
remarkable.  By way of comparison, a 14-inch diameter punched pipe has
about 10.9 square inches of open area per lineal foot.  Doerr bridge-slot well
screen of the same diameter with a 0.040 wide slot has 20.8 square inches
per lineal foot of well screen.  This increased open area lets a lot of water
enter the well very slowly.  Unlike punched well screen, bridge-slot screen
retains 100% of it's steel for maximum tensile strength.

How Important Is Controlling the Open Area?
It is very important, but there are some other things to consider too.  Like slot
size.  The exact size of the screen slot is determined by analyzing the
formation samples brought up during the drilling.  We want to make the slots
as wide as possible without letting any gravel-pack material through.  

Strength is important too.  Well screen takes a lot of punishment during
installation and has to resist crushing and collapse pressures which, in a
deeper well can be very high.

Material also makes a difference.  Where ground water is corrosive, stainless
steel or galvanized steel is recommended to provide a long service life.  
Where water is less corrosive or when price is a consideration, low carbon mild
steel is used to achieve excellent results.

Your driller can answer any questions you may have about Doerr Well
Screens or you can contact us directly.  We have spent more than 100 years
making better screens to make better wells.  We like to share what we have
learned with our customers.