Low melting point fiber (LMF) Filter

In the production of two-component polyester low melting point fiber (LMF), the type of filter used in the filtration process varies according to production needs and fiber quality requirements, but the following filters are usually selected:

1. Sintered metal filter element

Material: sintered from stainless steel, nickel-based alloy and other materials.

Features:

High temperature resistance (up to 300°C or above).

High strength and excellent pressure resistance.

Uniform pore size, providing precise filtration effect (several microns to tens of microns).

Applicability: used to remove small particle impurities and high-precision filtration.

Advantages:

Easy to clean and can be reused many times.

Long life, suitable for high-demand continuous production.

2. Metal woven mesh filter

Material: woven from stainless steel wire.

Features:

Wide pore size range (tens of microns to hundreds of microns).

Multiple layers can be stacked to form gradient filtration.

Applicability: Usually used for primary filtration to remove larger particle impurities.

Advantages:

Low cost.

Simple structure, easy to install.

3. Porous ceramic filter

Material: Made of high-temperature resistant ceramic material.

Features:

Extremely high heat resistance and corrosion resistance.

Ultrafine filtration (micron level) can be provided.

Applicability: Mainly used for high-precision filtration of melt spinning.

Advantages:

Suitable for harsh conditions.

Good interception effect on thermal degradation products.

4. Multi-stage filtration system

Combination method: Multi-stage filtration is usually used in actual production, combining different types of filters:

Primary filter: removes large particle impurities (such as particles that are not completely melted).

Intermediate filter: further removes smaller particles and gel-like substances.

Final filter: ensures high purity of the melt, and the pore size is usually several microns.

Filter selection factors

Quality requirements for fiber products:

For LMF with high fineness requirements, high-precision filters are required.

Melt characteristics:

When the melt viscosity is high, high-strength and high-temperature resistant filter materials need to be selected.

Equipment and process conditions:

The filter needs to adapt to the design of the spinning component, such as flow, pressure and temperature requirements.

Configuration examples of common filters

Primary filtration: metal woven mesh (100-300 microns).

Intermediate filtration: sintered metal filter element (20-50 microns).

Final filtration: sintered metal filter element or porous ceramic filter (5-10 microns).

This multi-stage filtration system can effectively remove impurities of different sizes and ensure the high quality and stability of LMF.

Maintenance and management

Regularly replace or clean the filter to prevent blockage from affecting the melt flow.

Monitor the pressure difference changes of the filtration system to determine the operating status of the filter.

Adjust the filtration accuracy according to the production process and optimize the filtration efficiency.