Tube and pipe blocking plugs provide a seal inside or at the end of pipe systems to block flow and allow for pressure testing, maintenance, or prevent unwanted material from entering the pipe. Mechanical blocking plugs have a manual closure mechanism that squeezes two plates together to compress and expand a rubber seal that presses against the internal walls of the pipe. Inflatable blocking plugs have a rubber bladder that inserts into a pipeline and fills with fluid to provide a temporary plug. A bypass is a removable cap that allows flow around the plug and helps release and clean out material that may have accumulated inside the pipe. Pipe testing equipment is used with blocking plugs to ensure the effectiveness of pipe joints and identify leaks and inflow in underground pipe systems.