Bridge Slotted Screen Pipe
Bridge slot screen have bridge opening arranged in rows and are staggered to reduce the negative effect on the screen's strength. Typically the slots are punched in a flat sheet that is subsequently rolled into a tube and welded. Regarded as the best choice of well tube filter, they are widely applied in a variety of fields in the developed countries. According to our after-sale services and the application experience at home and abroad, the advantages of bridge slot screens. When compared with other kinds of screens, can be listed as follows:
High strength through resistance to twisting, compressive, and tensile forces. A smooth bore that does not impede the passage of probes, tools, etc.
The special structure of the slot makes it difficult for particles to get stuck in the slot, thus bettering its discharge capacity.
The special bridge slots of screens help improving their mechanic strength.
Application of anticorrosive coasting will prolong the span lift of wells.
Slots and the diameter of bridge slot screens can be custom made to satisfy your needs.
Convenient to operate owing to various connecting methods between screens.
Lighter in weight and lower in price.
Open Area of LongZhongLong Screens
The main specification
Nominal diameter (mm) 146 159 219 273 325 377 426 529
ID 130 140 138 200 198 254 250 246 305 300 297 357 350 346 406 400 398 502 500 498
Wall thickness 5 5 6 5 6 5 6 8 5 6 8 5 6 8 5 6 8 6 7 8
Coupling outside diameter 146 160 162 220 226 274 278 278 325 328 329 377 378 379 426 428 432 529 530 531
Selection of slot size
Aquifer classification gravel Rough sand Medium sand Fine sand Mealy sand
Screening results (mm) 1-2.5 0.5-1 0.25-0.5 0.1-0.25 0.1-0.25
Bridge slots (mm) 3 1.5-2 1 1 0.75
Filling gravel spec (mm) 4-20 2-8 2-3 2-3 2-3
Filling gravel thickness (mm) 75-100 100 100-200 100-200 100-200
Mechanical property
Nominal diameter (mm) 159 219 273 325 377 426 529
Wall thickness 5 6 5 6 5 6 8 5 6 8 5 6 8 5 6 8 6 7 8
Tensile strength (KN) 230 270 320 390 400 490 653 480 570 760 560 670 893 630 760 1048 782 944 1296
Critical Collapse Strength (N/cm2) 520 690 340 450 170 230 306 136 203 270 128 183 244 92 135 203 90 136 186
Slot sizes and open area
Wall thickness 5 6 8
slot 0.75 1 1.5 2 2.5 0.75 1 1.5 2 2.5 0.75 1 1.5 2 2.5
Bridge lateral spacing 12.75 15 16
Bridge longitudinal spacing 45.50 52 62
Porosity 15.5% 17% 21% 24% 26.5% 14.5% 15.7% 18.9% 22.2% 25.7% 13.5% 14.5% 17.9% 21.2% 24.1%
Choice Of Material and Anticorrosive Coating Of Bridge Slot Screens
In the ordinary course of events, we choose galvanized or coated Q235(A3) carbon steel of stainless steel.
Anti-corrosive coating and anti rust coating are available in accordance with the requirements of customers.
Precautions When Laying the Screens
Checking the intensity of screens.
Preventing screens from colliding with hard substances.
Laying screens slowly and evenly.
Suspensory Screen-laying Methods
1- Steel Wire Ropes
2- Linking Sheaths
3- Casing plywood
4- Slot screen
5- Square Lumber
Optimum Exploitation Flow
Bridge sloth screens increase its flow to three to nice times, when compared with other kinds of screens with the same slot width, diameter and length.
LongZhonglong Scenes
Bridge slot screens
Strip slot screen
Lower Water Price
Water wells, when using bridge slot screens, can easily adjust themselves to aquifer and are regarded as a profitable mode of obtaining water:
Reducing the water velocity (V1>V2)
Reduction of pressure fall
Reduction of the head Loss (R1>R2)
Higher flow rate (HMT1>HMT2)
No sand in the water
Prolonging the life span of pumps
Adopt the suspensory screen-laying method.
Carefully check whether screens become deformed before laying them down, and adjust them when necessary.
Default slurry before laying down screens with the proportion of less than 1.2T/M3, otherwise, the blocking of slots will produce great pressure difference inside and outside the screens, leading to the possibility of deformation. Similarly, the use of nylon net will cause the deformation, therefore great pressure difference should be avoided.
Lay down screens steadily. If not smoothly, adjust the angle of screens and check whether they are deformed as a result of blocking before trying again. If screens cannot be lain down on account of blocking, forcibly trying should be forbidden.
Generally, compressors are used to flush wells, when pistons are necessary, operating pistons should be careful in case of the deformation of screens as a result of great pressure difference caused by the violent operation of pistons.
No clogging Water-carrying Section
Special construction of bridge slot screens make it possible to keep grains of sand it or screens, thus changing the direction of water flow and lessen its resistance.