Multiple dissolvable materials are becoming available in the energy industry. While dissolvable plasticsrnhave their applications, a dissolvable metal has distinct advantages over a dissolvable plastic for hydraulicrnfracturing.rnMultiple tests were performed to compare the characteristics of dissolvable metals and dissolvablernplastics. The two product families that were explored were dissolvable frac balls and dissolvable fracrnplugs. For direct comparison, frac balls and frac plugs were constructed using a dissolvable metal andrndissolvable plastic. For both dissolvable frac balls, the materials were tested for impact resistance. Forrnboth dissolvable frac plugs, the materials were pressure tested.rnThe dissolvable metal frac ball provided higher impact resistance than the dissolvable plastic frac ball.rnThe dissolvable metal frac ball survived impact at 19 bbl/min on ball-to-seat interference as small as 0.035rnin. When the same test was performed using a dissolvable plastic ball, the ball shattered and passedrnthrough the seat. The seat overlap needed to be increased to 0.125 in. before the dissolvable plastic ballrnwas able to consistently survive impact against the seat. For the frac plugs, the dissolvable plastic wasrnunable to be used as a bottom slip because of the anchoring loads generated while the plug sealed againstrndifferential pressure. The dissolvable metal was able to anchor these loads when used as the material forrnthe bottom slip. For a dissolvable plastic mandrel to survive the setting loads, it had to be set inrncompression. The dissolvable metal mandrel had no issue being set in tension, allowing for the operationalrnsetting procedures to be unchanged. Dissolvable plastic also required the inner diameter of the frac plugrnto be much smaller.rnUsing dissolvable metal instead of dissolvable plastic reduces design requirements for convertingrnnon-dissolvable downhole tools to dissolvable ones. Dissolvable metal provides an increased impactrnresistance, has no issues being set under tension, and allows for using smaller ball-to-seat overlaps, all ofrnwhich provide more flexibility for use in industry applications.
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