How To Use: Production Series
Attachment and Development Procedures
The new Production Series Qwater Well Developer surge block tools fit 4-inch and 6-inch Schedule 40 casing and screens. A check valve in the removable bottom of the tool allows for pumping sediments out of the well while surging. The 4-inch and 6-inch Qwater Well Developers can be used with a wireline (a cable attached to a 10-foot section of iron pipe) or drill rod.
Attachment of Tool – The top portions of the 4-inch and 6-inch surge blocks are fitted with a 1.5-inch female tapered NPT pipe thread for attaching a 1.5-inch male pipe thread. If a wireline is selected to lower the development tool into the well, it is recommended to attach a 10-foot long section of iron pipe directly to the top of the tool for weight to help lower the tool. Care should be taken not to over-tighten the threaded fitting. Hand tight plus one-half turn is sufficient. If the check valve assembly is to be used to pump water from the screen, a PVC riser should be attached to the top of the weight pipe and extended from total depth to land surface. A 90-degree elbow is recommended at the top to direct the purge water away from the wellhead. If the drill pipe is attached above the top of the tool, care should be taken to ensure that the weight of the drill rod does not crush the tool on the downstroke into the bottom of the well.
Development Procedures – Beginning at the bottom of the screen, using as short a stroke as possible (1-foot to 3-foot), begin slowly raising and lowering the tool. The polyurethane wipers fit very snugly and can damage even a metal screen if the upstroke is too fast. Screens are inherently weak and have great force pushing inward from the formation. Strong upstrokes can cause the screen to collapse due to the high suction (vacuum). Surging speed should not exceed 1/2 foot per second. Wells with slotted pipe screens generally take longer to develop than wells with wire-wrapped screens. If the check valve assembly is not used to remove the fines, the well development tool should occasionally be withdrawn from the well and the well screen pumped or bailed to remove fines in the bottom of the screen.
Continue to work the tool up and down, slowly, to surge the water back and forth, in and out of the well screen. The washing action will work the fines inward through the filter pack and screen, thus increasing the flow or permeability of the formation around the screen. Wells drilled with the drilling mud containing organic polymers may require an additive (such as Baroid’s Aqua-Clear®) to break down the gel strength of the mud.
If the check ball and riser are used to remove the muddy development water, continue for 2 to 5 minutes per foot of screen to be developed, depending upon the amount of fines (clay, silt) in the formation.
How To Use: Environmental Series
Selecting a Riser Material
Generally, the choices for risers include rolled polyethylene tubing or PEX tubing; 3/8-inch, 1/2-inch, and 5/8-inch rolls are generally available from hardware stores or plumbing supply vendors in 50-, 100-, and 300-foot rolls. Use of polyethylene tubing is limited to about 50 feet due to flexibility; however, depths beyond 50 feet can be obtained using PEX, a new type of rigid plastic pipe, which is growing fast in popularity. PEX has less “memory” when uncoiled from a roll. Once the coil is unrolled and straightened out, the plastic tubing will stay amazingly straight (stiff) and allow surging to depths of 100 feet or more.
PVC pipe works very well and is economical. Qwater Well Developers will readily connect to thin wall (160 psi) or Schedule 40 thicknesses. If the pipe can be glued together, this is the recommended method (up to 20-foot joints can be purchased if these longer lengths can be transported).
If glue (solvent weld) joints are unacceptable for environmental sampling reasons, pre-threaded pipe (usually available in 5-foot and 10-foot sections) is an excellent choice. This pipe is Schedule 40 with 4 to 6 square threads per inch (TPI) and has an O-ring to seal the joints. It is recommended that vise grips be used to hold the pipe at the top of the casing while sections of pipe are added.
Tubing Riser Attachment and Development Procedures
Polyethylene (Flex) Tubing Riser Instructions - Use off-the-shelf polyethylene tubing from a roll. Cut the end of the polyethylene square (clear, white or black) and turn the tubing four turns, or until tight, into the Qwater Well Developer. Roll the tubing, with the Qwater Well Developer attached, to the bottom of the well. Cut the tubing 5 to 6 feet above the top of the well. Insert the tubing end into a 5-gallon bucket (white, if available). Either clamp the tubing onto the bucket or drill a ½-inch hole into the bucket near the top and insert the tubing through the hole. Surge slowly up and quickly down. Allow one stroke per foot of distance to the water level to bring water to the surface (i.e., 20-foot water level = 20 strokes, etc.)
PVC (Rigid) Riser Instructions - Use 1/2-inch Schedule 40 or thin wall (DWV) PVC pipe from your local hardware store for the Qwater Well Developer riser. Tighten the small setscrew on top of the Qwater Well Developer into the PVC pipe. Lower the Qwater Well Developer into the well, adding PVC lengths as needed, holding each link at the top with vice grips. Once the Qwater Well Developer is at the bottom of the well, cut the PVC 2 to 3 feet above the top of the well casing and add the quarter-turn valve, with 90-degree elbow, and then add 6 to 7 feet of 1/2-inch ID clear vinyl tubing. (See Upper Valve Assembly photo.) Insert the tubing end into a 5-gallon bucket (white, if available). Either clamp the tubing onto the bucket or drill a 5/8-inch hole into the bucket near the top and insert the tubing through the hole. Note that the smaller size Qwater Well Developers (3/4-inch and 1-inch) and larger size Qwater Well Developers (1.25-inch, 1.5-inch, and 2-inch) have a tapered bell socket for gluing (solvent weld) or using a setscrew to secure the tubing in place. Deeper in the socket, below the bell, are 1/4-inch female pipe threads (in the smaller size QWDs) and 1/2-inch female pipe threads (in the larger size QWDs).
Development Procedures - Beginning at the bottom of the screen, push and pull the tubing up and down (up slowly / down quickly). If the well is unable to produce enough water, pinch or close off the flow with a quarter-turn valve so that the muddy slurry remains in the well, and is allowed to be used to surge fluid back and forth through the screen. Development time (usually 5-10 minutes per 5 feet of screen) depends on the range of grain sizes, screen slot size, length, and clay content. Generally, development should continue until the gritty material is no longer being pumped into the bucket. Note that since the Qwater Well Developer surge block method is a very aggressive method, the water may continue to appear muddy. Removing the flexible wiper from the PVC body after a few minutes of surging will allow the valve to clean the water more quickly, if so desired.
Note that the quarter-turn valve (photo 2) is used to keep fluid in the screen in low-producing wells; and the hole in the bucket holds the tubing (photo 8). Drill a 1/2-inch hole for 3/8-inch tubing or a 5/8-inch hole for 1/2-inch tubing. Clear vinyl tubing helps in observing the fluid.
Easy to Use - Six Steps
Step 1: Attach the Qwater Well Developer tool to 1/2-inch PVC or polyethylene pipe (for the 3/4-inch and 1-inch Qwater Well Developer, attach 3/8 ID polyethylene tubing)
Step 2: Lower the surge block to the bottom of the well and attach the valve assembly and tubing to the top of the PVC pipe
Step 3: With upper check valve closed, surge valve up and down five strokes
Step 4: Open the upper valve and surge (fast - down and slow - up) until water flows out of the tubing
Step 5: Continue to surge the well until the discharge is sediment free and/or the water clears
Step 6: Dispose of the Qwater Well Developer tool to avoid cross-well contamination
Note: Close the valve to keep water in the hole until flow is sufficient to keep the valve open while surging. One stroke per foot of water level depth (e.g., 30-foot water level = 30 strokes) usually brings water to the surface.