Here’s the rundown on degradable balls:
Time: We consider a ball to be degradable if it disappears in hours to days. Other manufacturers consider weeks to months to qualify as degradable.
Specific Gravity (SG): The (apparent) density of the ball measured as g/cc³ with water as the reference of 1.0 g/cc³. SG is important as many operators want to match the SG of the ball to that of the production fluid. Our patent-pending polymer and metal balls both have an SG of 1.7 – generally considered the “sweet spot”.
Fresh Water vs. Chloride Degradable: Our patent-pending polymer will degrade in 70° F fresh water, whereas our fresh-water degradable metal ball needs 210° F to degrade – or – the presence of some chloride in the fluid. The other metals we have need chlorides of varying levels to degrade. We have an acid-grade as well. The type of fluid the ball will be in is very important so that the ball does not degrade to quickly or too slowly.
Temperature: Virtually all degradable materials see the dissolve rate increase with an increase in temperature, and as noted above, some have a minimum initiation temperature. Our patent-pending polymer is unique in that it will degrade in “cold” water whereas virtually all other degradable polymers need near-boiling temperatures to begin to degrade.
Strength: Metals are usually considered by many to be stronger than polymer, but the extra strength may not be needed nor worth the extra cost. Polymer can be “tougher” than metal in certain situations.
Cost: Polymer costs less than metal.
So, reader… if you can find out the wellbore conditions according to the list I’ve presented you above, I will be glad to recommend a ball or two for you to test. Please contact us.