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Q&A: How does Ecodur hold up in high abrasion application areas?

Abrasion resistance of coatings really has more than one determinant property and is a fairly complex subject. The simplest property is to relate the respective hardness values with the material of higher relative hardness causing the one of lower relative hardness to yield or wear away when both are in contact under sufficient stress for the harder material to impinge upon the softer one. This property governs in the case of most metals and minerals.

Most organic coatings have within them minerals of widely varying hardness values. The hardness values of the overall cured organic coatings are normally measured using Shore D (and Shore A) hardness gauges. A typical measured hardness of a relatively hard epoxy coating at about Shore D 80 could have hard and/or soft minerals included within the coating matrix varied while having no change in its overall hardness value. The included harder minerals such as ground quartz do tend to improve the abrasion resistance of such relatively hard coatings such as commonly used epoxies.

Another important property when determining abrasion resistance of coatings is that of elasticity/resilience. This relates to energy absorption capabilities. For example, rubber coatings are relatively soft (often less than Shore D 50) but are widely used for abrasive slurries, especially relatively slow moving ones. They generally do not contain hard minerals yet outperform the harder epoxy coatings in many abrasive applications. The ability of the coating to absorb the energy of the harder impinging materials and effectively “bounce” them away is an important one. Harder coatings that do not effectively absorb the energy of the impinging materials tend to abrade relatively quickly. If the energy of the relatively harder impinging particles in the slurry exceed the energy absorption capabilities of the relatively softer coating, the coatings will generally fail quite quickly. Harder coatings tend to have relatively low energy absorption capabilities and therefore tend to become ground down or abraded away at a rate that can often be predicted relatively accurately.

The Ecodur coatings are normally formulated to cure to a Shore D 50 hardness and have sufficient elasticity/resilience to absorb the energy from relatively slow moving slurries such as those normally found in the well head mud tubs. It is important to have enough coating thickness to provide enough of a cushion to absorb the impact energy of the hard particles in the slurries and redirect or bounce them away from the coated surface.