In the chemical, pharmaceutical, environmental protection and other industries, the transportation of corrosive media remains a key challenge. As a core fluid transportation equipment, the material selection of centrifugal pumps directly affects production safety and cost control.
Among them, lined fluoroplastic centrifugal pumps and perfluoroplastic pumps have become the mainstream choice due to their excellent corrosion resistance.
But what is the difference between lined fluoroplastic centrifugal pumps and perfluoroplastic pumps? How to choose a suitable pump according to the working conditions? This article conducts an in-depth analysis based on international standards and engineering practices.
Difference 1: Structural difference between lined fluoroplastic centrifugal pumps and perfluoroplastic pumps
1. Lined fluoroplastic centrifugal pump
Structural features: Metal shell (such as cast iron, stainless steel) lined with fluoroplastic (such as PTFE, F46). Impeller and pump cover are metal inserts coated with fluoroplastic.
Advantages of lined fluoroplastic centrifugal pumps:
High mechanical strength, can withstand pipeline weight and mechanical impact, suitable for high pressure and large flow occasions.
Wide operating temperature range (-20℃ to 180℃). Use bellows mechanical seal to minimize leakage risk.
Typical model: IHF series, widely used for conveying acid, alkali and salt solutions.
2. Perfluoroplastic pump
Structural features: The pump head (including pump body and impeller) is all made of fluoroplastic (such as PTFE, FEP, PFA) injection molding, and there is no metal contact with the medium.
Advantages of perfluoroplastic pump:
Resistant to strong corrosion (such as concentrated sulfuric acid, hydrofluoric acid) and short-term high temperature (up to 200°C).
Smooth surface, reducing fluid resistance and improving efficiency.
Typical model: FSB series, suitable for small-diameter pipelines and low-flow occasions.
Difference 2: Performance difference between lined fluoroplastic centrifugal pump and perfluoroplastic pump
Difference 3: Application scenarios and media of lined fluoroplastic centrifugal pump and perfluoroplastic pump
1. Application and applicable media of lined fluoroplastic centrifugal pump:
Chemical industry: conveying sulfuric acid (concentration ≤50%) and nitric acid.
Pharmaceutical industry: high-purity liquid transportation, in line with FDA hygiene standards.
2. Application and applicable media of perfluoroplastic pumps:
Electroplating industry: circulating highly corrosive liquids such as hydrofluoric acid and chromic acid.
Semiconductor industry: ultra-pure chemical transportation to prevent metal ion contamination.
Difference 4: Corrosion-resistant pump selection guide
1. Medium characteristics
Perfluoroplastic pumps are preferred for highly corrosive media (such as hydrofluoric acid and molten alkali).
Lined fluoroplastic centrifugal pumps are used for particle-containing media or high-temperature media (such as mud and boiler water), with better wear resistance and pressure resistance.
2. Process parameters
Flow rate and head: Perfluoroplastic pumps are suitable for low flow rates (≤30m³/h) and low head (≤30m), and lined pumps can meet larger flow requirements.
Pipe diameter: Perfluoroplastic pumps are suitable for pipe diameters ≤80mm, and lined pumps support larger pipe diameters.
3. Cost and maintenance
For customers with moderate corrosion and limited budgets, perfluoroplastic pumps have a higher cost-effectiveness.
Lined pumps can reduce long-term continuous operation costs due to simpler maintenance and longer service life.
4. International standards
Lined pumps comply with ISO 2858 (centrifugal pump design) and ASME B73.3 (chemical pump standard).
Perfluoroplastic pump materials require ASTM D4894 (PTFE molding standard) certification.
Difference 5: Summary and recommendations
Perfluoroplastic pumps are preferred: extremely corrosive, particle-free, low-flow scenarios.
Lined fluoroplastic centrifugal pumps are preferred: media containing solids, high pressure/temperature, and long-term operation.