wedge wire screen filter

Wedge wire mesh filters, also known as V-type wire mesh filters, are high-precision, high-strength filtration devices widely used in water treatment, mining, food processing, petrochemicals, and other industrial fields. Their core advantages lie in the high filtration accuracy, anti-clogging properties, and ultra-long service life brought by the wedge wire structure, distinguishing them from traditional woven mesh and perforated mesh filters, enabling stable operation under complex working conditions. 

I. Core Structure and Working Principle

1. Key Structural Components

The core component of the wedge wire mesh filter is the "wedge wire mesh," which consists of two parts:

Wedge Wires (V-type Wires): As the main material of the filter layer, they have a wedge-shaped cross-section (narrow at the top and wide at the bottom), typically made of corrosion-resistant materials such as stainless steel (304, 316L) and Hastelloy. The wire surface is smooth, with uniform gaps, and filtration accuracy can be customized from 0.01-20mm according to requirements.

Support Wires (Longitudinal Ribs): Arranged perpendicular to the wedge wires, they provide fixation and support, ensuring the mesh does not deform under high pressure and high flow rate conditions. The support wires and wedge wires are connected by welding (resistance welding, laser welding) to form a robust "rigid screen structure" with no risk of loosening or falling off. In addition, the filter as a whole includes components such as a shell, inlet and outlet interfaces, drain valve, and fixed flanges, which can be designed in different shapes such as cylindrical, conical, and flat plates depending on the application scenario. 

2. Working Principle The filtration process follows a "outer inlet, inner outlet" or "inner inlet, outer outlet" flow design, specifically as follows: Raw liquid entry: The liquid/solid mixture to be filtered enters from the filter inlet and flows through the outer (or inner) side of the wedge wire screen. Precision filtration: The liquid (or qualified fine particles) in the mixture passes through the uniform gaps between the wedge wires and enters the interior of the screen; while impurities and large particles are trapped on the screen surface, forming a "filter cake layer" (which can be removed by backwashing in some operating conditions). Clean output: The filtered clean fluid is discharged from the outlet, completing the filtration process. Sewage Discharge/Backwashing: When impurities accumulate on the screen surface, causing a rise in pressure differential, the slag can be discharged directly by opening the drain valve, or the backwashing system (high-pressure water/air) can be activated to flush the impurities away from the screen, achieving maintenance without shutting down the system. 

II. Main Types and Applicable Scenarios Based on structural form and application requirements, wedge wire screen filters can be divided into the following categories, each corresponding to different application scenarios: 

1. Cylindrical Filter Structural Features: The screen is cylindrical, installed vertically or horizontally, occupying a small area, suitable for high-flow-rate conditions. Applicable Scenarios: Municipal sewage treatment, industrial circulating water filtration, groundwater sand removal, agricultural irrigation water filtration, etc. For example, in steel plant circulating water systems, it can remove suspended solids and rust from the water, protecting heat exchangers from clogging. 

2. Conical Filter Structural Features: The screen is conical, utilizing gravity to assist in slag discharge; impurities easily accumulate at the bottom of the cone, resulting in high sewage discharge efficiency. Application Scenarios:Mining (e.g., gold and copper mines) slurry filtration, coal washing wastewater treatment, fruit juice residue removal in food processing, syrup filtration, etc. For example, in flour mills, it can filter bran particles from flour, improving product purity.

3. Plate Filter: Structural Features: The screen is flat, multiple plates can be stacked, providing a large filtration area, suitable for low-pressure, low-viscosity fluids.

Application Scenarios: Catalyst filtration in the chemical industry, pharmaceutical liquid clarification, edible oil refining filtration, etc. For example, in antibiotic production, it can remove mycelium from the liquid, ensuring drug quality.

4. Self-Cleaning Filter: Structural Features: Built-in scraper, brush wheel, or backwashing device, automatically monitors pressure differential and initiates cleaning without manual disassembly.

Application Scenarios: High-viscosity fluid filtration (e.g., crude oil, asphalt), continuous production processes (e.g., white water recovery in paper mills), unattended remote areas (e.g., oilfield wellhead filtration). 

III. Core Advantages and Comparative Advantages Compared to traditional filtration equipment (such as woven mesh filters and bag filters), wedge wire mesh filters have significant advantages: 

1. High Precision and Stability The wedge wire gaps are machined using precision molds, with an error controllable within ±0.01mm, resulting in filtration precision far exceeding that of woven mesh (where gaps are prone to deformation); The rigid structure is impact-resistant and vibration-resistant, maintaining stability even under high temperature (-200℃ to 500℃) and high pressure (up to 10MPa) conditions, without gap widening due to pressure changes. 

2. Anti-clogging and Easy to Clean The smooth surface of the wedge wires and the inverted conical gap (wider on the outside and narrower on the inside) design prevent impurities from easily getting stuck, reducing the risk of clogging; It supports multiple cleaning methods such as backwashing and mechanical scraping, offering high cleaning efficiency and rapid restoration of filtration performance, eliminating the need for frequent filter media replacements. 

3. Long Lifespan and Economy: Made of corrosion-resistant materials such as stainless steel, it is wear-resistant and corrosion-resistant, with a service life of 5-10 years, 3-5 times that of woven mesh filters; It eliminates the need for frequent filter media replacements, reducing consumable costs and downtime for maintenance, resulting in superior long-term economic efficiency.

4. Environmental Protection and Compliance: The filter media is 100% recyclable, with no secondary pollution; It meets food-grade (FDA certified) and pharmaceutical-grade (GMP standard) requirements, making it suitable for applications with high hygiene standards.