If you had read our guide on the 5 important steps in selecting an AODD Pump, you would know by now how important material selection is to the process. Given that most AODD Pump manufacturers offer a wide range of material selection for the body, diaphragm, o-ring, ball and ball seat, it can be quite a handful to know which the right material is to go with.
Today, we want to focus on a material that is available for selection for the body of an AODD Pump: PVDF.
Why? It is because, more often than not, I have found that many factories in Malaysia are using polypropylene (PP) when the chemical they are pumping actually requires a PVDF. For instance, a well-known chemical manufacturer was found using PP for Nitric Acid 68%. The reason? PP is cheaper. Of course, cheap is not always cheaper and it always comes at a price, and the price is usually premature malfunctioning of the AODD Pump.
What is PVDF?
PVDF stands for polyvinylidene fluoride, a type of semi-crystalline thermoplastic fluoropolymer that exhibits high corrosion resistance against acid and bases, possesses good abrasion resistance and is high-temperature resistant (over 100°C).
For this reason, PVDF is an ideal choice for use as the wetted part for most chemical pumping applications, commonly found as the pump head material for dosing pumps, thermoplastic centrifugal pumps as well as the body of AODD Pumps.
How Does PVDF Compare to Other Materials?
Polypropylene
PVDF is resistant to a wider range of chemicals than polypropylene, and is able to withstand most acids and caustics of higher concentrations than polypropylene could. It is also a very strong plastic and can handle abrasion better.
Of course, the superior quality of the PVDF comes at a higher price than polypropylene. Hence, if the chemical you are pumping is not more aggressive or higher temperate than polypropylene can handle, then choose polypropylene. However, for highly aggressive chemicals or high operating temperature or abrasive chemicals, then the PVDF would be the best choice in the long run.
Stainless Steel
Stainless Steel is also offers excellent chemical resistance, abrasion resistance and has high temperature resistance. Its mechanical strength far exceed those of PVDF, and so does its weight.
For food and beverage industry which needs to comply with FDA requirement, then stainless steel would be your only choice. However, in mobile application, where weight is of importance, the PVDF would be a better option.
Aluminium
Aluminium is another choice for the body material of your AODD Pump, although it has the most inferior chemical resistance compared to PVDF, polypropylene and Stainless Steel. What it does offer, though, is high abrasion resistance than the plastic options but at a much lower weight and price than Stainless Steel.
It is suitable for outdoor use or for use in harsh physical environments like in a mine. For pumping less aggressive chemicals with high solid contents like sludge or latex, aluminium is also a good choice. For aggressive chemicals, the PVDF would be a recommended choice.
When should you use PVDF?
So, what chemicals must you use a PVDF instead of the other materials? Here is a list of chemicals we have compiled for your convenience. The list is by no means an exhaustive one:
Nitric Acid 68%, Sulfuric Acid 98%, aniline hydrochloride, aqua regia, bromine, chlorine dioxide, hydrofluoric acid, hydrobromic acid, potassium hypochlorite, trichlorethylene, sulphur chloride, sodium peroxide, potassium permanganate, pentane, nitrous acid, benzene, diethyl ether, chromic acid 50%, chlorine.
Where can you get AODD Pump in PVDF Material in Malaysia?
If you looking for an AODD Pump with high standard of quality and a good track record operating in Malaysia’s industries and climate, look no further than the Fluimac Phoenix AODD Pump. Autoflo Technology Sdn. Bhd. is the official distributor for Fluimac Phoenix AODD Pump in Malaysia. Please contact us at info@ autoflotechnology.com for more information or enquiry.
