Stainless steel lined fluoropolymer flange gate valve PFA, FEP

What is Z41F46-16P stainless steel fluoropolymer-lined gate valve?

Z41F46-16P adopts stainless steel valve body and fluorine-containing material lining, and achieves pipeline opening and closing through gate lifting. The stainless steel metal substrate and internal lining layer play different roles, and the actual corrosion resistance performance should be judged jointly with the internal and external environment.

Current product parameters

The current specification is DN50-DN500, with a pressure rating of PN16/Class150. The valve body can be selected from 304 (CF8) or 316L (CF3M), and the lining adopts the PFA or FEP scheme. The specific material combination shall be confirmed according to the order and technical agreement.

Why do stainless steel valve bodies still need to be lined with fluorine?

Stainless steel can improve the corrosion resistance of metal substrates in certain environments, while PFA/FEP lining is used to reduce direct contact between process media and metal valve bodies. For media with strong corrosiveness or high material compatibility requirements, this combination structure can be adopted according to actual working conditions.

How to choose between 304 and 316L?

The alloy composition and corrosion resistance characteristics of 304 and 316L are different. Although the medium side is mainly isolated by a lining layer, the valve body material still needs to consider external corrosion environment, temperature, mechanical load, and project material specifications.

How to choose between PFA and FEP?

Both belong to fluorine-containing materials, but they are not exactly the same material. The selection should be confirmed based on the composition, concentration, temperature, pressure, and lining manufacturing structure of the medium, and the parameters of the two cannot be unconditionally exchanged.

What information is required for selection?

The name, concentration, temperature, and pressure of the medium should be provided DN、 Flange standards, 304 or 316L valve body requirements, PFA/FEP lining requirements, opening and closing frequency, as well as special conditions such as vacuum, particle, and flushing.

Z41F46-16P Stainless Steel fluoropolymer-lined Gate Valve Common Problems

Do I still need fluorine lining after using 316L valve body?

Whether fluorine lining is required depends on the medium and project requirements. 316L itself has a certain degree of corrosion resistance, but it cannot replace the selection of lining materials under all corrosive conditions.

Which is definitely better, PFA or FEP lining?

There is no unified conclusion that deviates from the working conditions, and the selection should be based on the medium, temperature, pressure, and product lining structure.

Can stainless steel lined fluorine gate valves be used for throttling in the long term?

Generally, fully open and fully closed isolation are still the main purposes, and long-term operation with small openings may increase the risk of erosion of the gate, valve seat, and lining.