US Patent 10544643 Hydraulic fracturing systems and methods

A well stimulation system includes an inlet fluid conduit connected to a manifold, and a first wellhead assembly connected to the manifold, wherein the wellhead assembly includes a frac tree, a wellhead coupled to the frac tree, wherein the wellhead is in fluid communication with a first well, wherein the frac tree of the first wellhead assembly is configured to inlet a stimulation fluid from the manifold to the first well along a first fluid flowpath extending through the frac tree, wherein the frac tree of the first wellhead assembly is configured to outlet well fluid from the first well to the manifold along the first fluid flowpath.