Insert valve and method of insertion into pressurized pipelines

A replacement valve assembly 40, comprising:

• a valve body having a right side and a left side, the valve body comprising a right side cylinder, a left side cylinder, and a central chamber between the right side cylinder and the left side cylinder, wherein the central chamber, the right side cylinder, and the left side cylinder are disposed along a longitudinal axis and are in fluid communication so as to form a fluid passage between a right side cylindrical opening of the right side cylinder and a left side cylindrical opening of the left side cylinder, and wherein the central chamber comprises a rotatable valve;
• and
• a right side cut-covering assembly in an interior of the right side cylinder and a left side cut-covering assembly in an interior of the left side cylinder, wherein each cut-covering assembly comprises an elastomeric seal, a spring tube, and a first cross brace, wherein an exterior surface of the elastomeric seal contacts an interior surface of the cylinder, an interior surface of the elastomeric seal contacts an exterior surface of the spring tube, and the first cross brace extends within the fluid passage of the valve body between a first position on the interior surface of the spring tube and a second position on the interior surface of the spring tube,
• wherein when the rotatable valve is rotated between a first position and a second position, a first medial edge of the valve contacts the first cross brace of the right side cylinder and urges a right side end of the right side cut-covering assembly out of the right side cylindrical opening, and simultaneously a second medial edge of the valve contacts the first cross brace of the left side cylinder and urges a left side end of the left side cut-covering assembly out of the left side cylindrical opening.