Large & Complex Machining
Bronte Precision are a Made in Yorkshire Bronze Member
When pumping any chemical, material selection is a crucial factor. Here is an overview on popular materials used in pumping applications and their compatibility with chemicals.
Most often used in non-sanitary applications, Cast, Ductile and Grey Irons are commonly used throughout pumping applications thanks to their high tensile strength and low cost point. They do however have a limited compatibility range due to their high carbon amount and would suffer damage when in contact with Acetic Acids, Ammonium Phosphates, Chromic Acids, Lactic Acids, Nitric Acids and Tartaric Acids.
Often selected when Iron is not suitable, Stainless Steels have a good range of chemical compatibility and is most often used in sanitary and food applications, especially where a greater resistance of abrasion is required. The main chemical that Stainless Steel will struggle with are high concentrated acids. Most noticeably Sulfuric and Hydrofluoric Acids which will have a corrosive effect, especially at high temperatures.
Super alloys are a complex mix of different materials, most often containing Nickel and Chromium. They are selected for their high level of hardness and wear resistance and some examples would include Inconel and Monel. In general terms these super alloys can be used in conjunction with a broad range of chemicals, and are often specified for use in conjunction with highly concentrated chemicals and viscous fluids.
Teflon is a popular brand name of PTFE is often used in chemical pumping applications as it is chemically inert to nearly all sources. Many manufacturers will use Teflon in conjunction with Iron giving them the benefits of the strength and value of iron with the high chemical compatibility of PTFE. The main drawbacks of Teflon are that it doesn’t provide much abrasion resistance, so may not be suitable for more viscous fluids.
One word of caution on compatibility charts. None are completely comprehensive and is always good practice to reference multiple charts when researching an application as often materials are rated differently by different manufacturers. It’s also important to factor in other factors such as temperatures, sunlight and strength of the chemicals your pump will come into contact with.
Bronte Precision are sub-contract machinists, working from manufacturer’s drawings to produce large sized and complex components with a niche in pumping applications. We are fully ISO certified and deliver across the UK.