How to Choose Appropriate Wedge wire Construction & Flow Direction?

Selecting the appropriate construction and flow direction for a wedge wire screen depends on the specific requirements of your application and the type of filtration or separation you need to achieve. We provide axial slots and radial slots in FOTI and FITO flow direction. Here are introduction and suggestion to help you make the right choices:

  • Definition
  • Radial External Type
  • Radial Internal Type
  • Axial External Type
  • Axial Internal Type
  • Reinforcement Type
  • Consult with our specialists
Four different wedge wire construction and flow directions.
Definition
  • Wedge wire construction/structure – The specific arrangement and design of surface wire and support rod
  • Flow direction – The orientation or path of fluid flow through a wedge wire screen or filtration system
  • FOTI – flowing direction is From Outside To Inside
  • FITO – flowing direction is From Inside To Outside
  • Radial Slots – The slot orient along the diameter of the screen in a parallel fashion
  • Axial Slots – The slots orient along the length of the screen in a parallel fashion
Radial External Type

Radial external wedge wire tubes are composed of axial support profile rods and radial surface Vee wires, which are wrapped around support wires and attached to each other by resistance welding.

  • When the flow direction is from outside to inside (FOTI), the flat side of the surface wire is on the outside of the tube, shown as figure 1-1
  • When the flow direction if from inside to outside (FITO), the flat side of the surface wire is on the inside of the tube, shown as figure 1-2. It is also called reverse wedge wire screen tube.
A wedge wire screen tube with radial external structure and FOTI flow direction.
Figure 1-1 Radial External – FOTI Standard
  • Standard type for most applications
  • Precision openings
  • Economical production
A wedge wire screen tube with radial external structure and FITO flow direction.
Figure 1-2 Radial External – FITO
  • Also named as reversed welding, which radial external surface screen wire’ sharp point outside
  • Backwashing
  • Inverted circumferential external surface profiles
Radial Internal Type

Radial internal wedge wire types are rolled from flat wedge wire screen panels not continuously spirally wrapped around axial support profiles, that means there are many welding joining points and only flow in one direction (FITO), shown as figure 2.

A wedge wire screen tube with radial internal structure and FITO flow direction.
Figure 2 Radial Internal – FITO
  • Smooth internal screen surface
  • Facilitates cleaning with an internal axial-movement scraper
  • Economical easy for small quantity and any size production
Axial External Type

Axial external wedge wire screen tube or cylinder is rolled from flat wedge wire screen panels and is composed of radial support profile wires and axial surface screen profile wires, which are axial outside the support wire. Because of the flat side of surface screen Vee wires on the outside of the screen, the flow direction of this type is commonly from outside to inside (FOTI), shown as figure 3-1. We can produce specially designed wedge wire tubes, which the flow direction is from inside to outside (FITO), shown as figure 3-2..

A wedge wire screen tube with axial external structure and FOTI flow direction.
Figure 3-1 Axial External – FOTI
  • Standard type
  • Economical and easy production
  • Flat side of wedge wire outside
A wedge wire screen tube with axial external structure and FITO flow direction.
Figure 3-2 Axial External – FITO
  • Customized type
  • Not widely used
  • Flat side of wedge wire inside
Axial Internal Type

The axial wedge wire screen tube or cylinder is comprised of surface screen profile wires oriented axially inside of the screen tube and support profiles oriented radially outside of the tube. Because of screen Vee wires on the inside of the screen, the flow direction of this type is commonly from inside to outside (FITO).

There are two types based on the slot and filter size: the first type is rolled from flat wedge wire screen panels, resulting in multiple welding joining points, shown as figure 4-1, while the second type involves the continuous spiral wrapping of support wires around axial surface wedge wires, shown as figure 4-2.

An axial internal wedge wire screen tube rolled from flat screen has FITO flow direction.
Figure 4-1 Axial Internal – FITO Joint Support
  • Smooth internal screen wire surface, ID can be processed, no welding molds limited.
  • Economical utility with several welding joining points
  • Facilitates cleaning with an internal axial-movement scraper
  • The flow moves across the wire edges for effective dewatering
An axial internal wedge wire screen tube with spirally wrapping welding support profiles has FITO flow direction.
Figure 4-2 Axial Internal – FITO Continuous Support
  • Smooth internal screen wires surface, one welding molds suit for one screen ID, higher production costs.
  • Without a welding seam, more stronger strength
  • Facilitates cleaning with an internal axial-movement scraper
  • The flow moves across the wire edges for effective dewatering
Reinforcement Type

Except of figure out the flow direction, structure of screen surface profile wires and support wires, there are also a few common strengthening forms for the wedge wire screen tubes or cylinders.

A wedge wire screen with internal reinforcement perforated tube

Reinforcement perforated tube

A wedge wire screen with internal reinforcement spiral rods

Reinforcement spiral ribs (flange ring, round steel & square steel)

A wedge wire screen with internal cross reinforcement plate

Reinforcement plates

A wedge wire screen with external reinforcement ring rib

Reinforcement external ring ribs

A wedge wire screen with external reinforcement ring rib

Reinforcement external vertical ribs

A wedge wire screen with external reinforcement ring rib and vertical ribs

Reinforcement external ring ribs and vertical ribs

A wedge wire cylinder with light surface and precise dimension.
Consult with our specialist

If you have any doubts, you can consult our experts to provide tailor recommendation according to your applications.