Spot welding circular Filter & Framed Screen Packs

Multilayer filter mesh usually has two processing technologies, namely connecting the multilayer mesh together through welding points, or connecting the multilayer mesh together through aluminum plate or stainless steel plate bound technology. Both processes can achieve layer-by-layer filtration, so how should we choose?

Multilayer filter screen is connected by multiple equidistant welding points

Advantages
1. High strength and pressure resistance
- The welding points directly fix each layer of mesh, without gaps between layers, with high overall rigidity, and can withstand high pressure (such as above 30MPa) and mechanical impact.
2. Compact structure
- No additional edging material, small thickness, suitable for installation environments with limited space.

Disadvantages

1. Welds are prone to corrosion weak points

- In chloride ion environments (such as seawater), welds may corrode first, and special welding materials (such as duplex stainless steel) are required.

2. Risk of thermal deformation

- Multilayer welding is prone to local deformation due to heat accumulation, affecting the uniformity of pore size.

Typical application areas

1. High-temperature and high-pressure melt filtration

- Plastic extruder: Filter carbides in molten PE and PVC, and withstand high temperatures of 300°C and pressures of 20MPa.

- Chemical fiber spinning: Intercept gel particles in PET melt to ensure fiber uniformity.

2. Petrochemical

- Filtration of high-sulfur oil products, the weld structure is resistant to sulfidation corrosion.

3. Nuclear power and heavy industry

- Intercept metal debris in coolant and resist high-pressure pulse impact.

Framed Screen Packs

Advantages

1. Strong edge protection

- The hemming frame protects the edge of the mesh to prevent curling or deformation, and is suitable for working conditions with particle scouring (such as sewage treatment).

2. Multi-layer scalability

- Supports more layers (such as 5-10 layers), and maintains overall stability through the hemming frame.

3. Uniform corrosion resistance

- The edging and mesh are made of the same material (such as 304/316L), and there is no risk of differential corrosion in welds.

4. Controllable costs

- In mass production, the automated folding process can reduce processing costs.

Disadvantages

1. Weak pressure resistance

- Depends on the support of the edging frame, and overall deformation may occur under high pressure (thickening of the edging or adding support ribs is required).

2. Sealing depends on the process

- Sealant or welding fixation is required between the edging and the mesh, and micro-leakage is prone to occur when the process is poor.

3. Large weight and volume

- The edging frame increases the overall weight and is not friendly to lightweight design.

Typical application areas

1. Food and pharmaceutical industry

- Filtration of liquid foods (such as milk and juice), no welding gaps, in line with hygiene standards.

2. Water treatment and environmental protection

- Sewage treatment: multi-layer interception of sludge, edging structure to resist particle erosion.

- Seawater desalination pretreatment: 316L stainless steel edging, resistant to salt spray corrosion.

3. Laboratory precision filtration

- Customized multi-layer aperture gradient (such as 100 mesh ~ 1000 mesh), edging to ensure structural stability.

4. Ventilation system

- Intercept dust and PM2.5, stainless steel frame is resistant to humid environment.

Summary

Welding point screen packs:

- Advantages: high strength, high temperature and high pressure resistance, super strong sealing.

- Limitations: weld corrosion risk, high maintenance cost.

- Applicable: chemical melt filtration, nuclear power, petroleum and other high-demand scenes.

Frame screen packs:

- Advantages: edge protection, multi-layer expansion, uniform corrosion resistance.

- Limitations: weak pressure resistance and large volume.

- Applicable: food and pharmaceutical, water treatment, laboratory and other medium and low pressure or hygiene sensitive fields.

Core logic of selection:

1. High temperature and high pressure → welding point screen packs.

2. Multi-layer precision filtration → frame screen packs .

3. Corrosive environment → give priority to edging with the same material, or high-grade welding materials.

4. Cost control → bounded structure is more suitable for mass production.