Sealing rubber ring materials commonly used in acid-resistant chemical pumps

I often hear feedback from some customers: the acid-resistant chemical pump used by the customer on site is not corroded, but there is leakage at the joint of each part of the pump body. In a situation like this, there is usually a problem with the sealing rubber ring between the components, either it is not installed in place, or it is corroded.

So what exactly is the sealing rubber ring of an acid-resistant chemical pump?

There are two kinds of materials used in the o-shaped sealing ring in acid-resistant chemical pumps: NBR and VT materials.

NBR material is also called nitrile butadiene rubber, which is a copolymer of butadiene and acrylonitrile. The advantages of this chemical material are that it has particularly good resistance to gasoline and aliphatic hydrocarbon oils, good heat resistance, good air tightness, wear resistance and water resistance, and strong adhesion. Mainly used in hydraulic lubrication system.

The disadvantages are poor cold resistance and ozone resistance, low toughness and elasticity, poor acid resistance, poor electrical insulation, and poor resistance to polar solvents. Operating temperature range: 59℃~121℃. Mainly used in the manufacture of various oil-resistant products, such as hoses, sealing products, etc.

VITON material is abbreviated as VT and also called hexafluoro rubber. Its advantages are aging resistance, oil resistance and abrasion resistance, and it is more used in sealing rings. Acid and alkali resistance, resistance to most oils and solvents (except ketones and esters), and good ozone resistance. It is generally widely used for seals in automobiles, motorcycles, B and other products, and chemical plants. The operating temperature range is -20℃～260℃ , There are special VT materials available for low temperature resistance when used in low temperature requirements, which can be used up to -40 ℃, but the price is higher.

Compared with NBR material, VT material has stronger acid and alkali resistance, but its cold resistance is poor, and the price is much higher than NBR material; VITON is fuel system seal and hose, O-ring, shaft seal, expansion Particularly suitable fluoroelastomer for joints and gaskets.

The performance of any material is not omnipotent. It should be noted that when choosing the material of the acid-resistant chemical pump body, you must confirm the material of the sealing rubber o-ring inside. In this way, it can be ensured that the acid-resistant chemical pump will not leak when transporting acid and alkali media.