US Patent 11181222 Internal pipe lining system having self-propelled, self-powered propulsion devices

Self-propelled, self-powered, propulsion devices as part of pipe lining system adapted to create an internal liner member on a pipe or other tubular structure, the system being the combination of a sprayer apparatus, an umbilical member connected to the sprayer apparatus, wherein the umbilical member supplies no power or communications to the propulsion devices, and a plurality of propulsion devices mounted externally onto the umbilical member in a removable manner. The spraying apparatus and propulsion devices are independently powered and controlled such that each may be accelerated or decelerated as required to maintain the sprayer apparatus at a constant speed during the application process.