Pipe coupling

A reinforced plastic pipe having an inner pipe section of a first inner diameter reinforced by a series of outwardly extending reinforcing portions of a second greater diameter that reinforce and increase the strength of said inner pipe section, wherein said reinforced plastic pipe is a corrugated reinforced plastic pipe with a series of spaced reinforcing corrugations selectively connected to said inner pipe section;

• a male/female connector with one end of said reinforced plastic pipe having a two stage male connector and an opposite end of said reinforced plastic pipe having a two stage female connector sized to receive a male connector of the same construction as said two stage male connector;
• said male connector including a first spigot portion with an inner wall of said first diameter and an outer wall section of a diameter less than an outer diameter of said female connector, said first spigot portion is of a length at least equal to a length of said reinforced plastic pipe necessary to fully include two adjacent corrugations;
• said male connector further including a second spigot portion having an inner diameter the same as said first spigot portion and a plurality of spaced outwardly extending reinforcing members separated by inwardly extending recesses, said second spigot portion is of a length at least equal to a length of said reinforced plastic pipe that fully includes three adjacent corrugations;
• and
• said female connector at a free end thereof includes a first cuff portion with an inner wall defining an outer connecting cavity sized to receive and engage said second spigot portion and an inner cuff portion defining a smaller in diameter tubular cavity merging with said outer cavity and said inner cuff portion being of a size to receive and closely sleeve said first spigot portion, and
• wherein said first spigot portion is of reduced stiffness relative to said second spigot portion.

A reinforced plastic pipe comprising:

• two extruded layers forming a generally smooth inner tubular wall and a corrugated or ribbed outer wall that reinforces and increases a strength of said pipe;
• a male connector having a first spigot portion and a second spigot portion having an outer diameter greater than an outer diameter of said first spigot portion, said second spigot portion having a plurality of corrugations;
• and
• a female connector having an inner cuff portion and an outer cuff portion having an inner diameter greater than an inner diameter of said inner cuff portion, said inner cuff portion configured to receive and engage said first spigot portion and said outer cuff portion configured to allow said first spigot portion to pass through to said inner cuff portion and to receive and engage said second spigot portion, and
• wherein said outer diameter of said first spigot portion is approximate to the inner diameter of said inner cuff portion, and
• said outer diameter of said second spigot portion is approximate to the inner diameter of said outer cuff portion, and
• said smooth inner tubular wall runs a length of said pipe including an entire length of said female connector such that an inner diameter of said smooth inner wall increases or remains the same from a start of said inner cuff portion to said free end of said female connector.