Lightweight high compressive strength drainage pipe

Claim 2

A corrugated resilient plastic drainage pipe having a compressive strength of at least 1,000 pounds per linear foot and being of lightweight construction with a wall thickness no greater than about one-sixteenth inch and weighing no more than about 6 ounces per linear foot, said pipe having spaced apart successively arranged annular ribs with interconnecting annular valley portions therebetween defining corrugations along the periphery of the pipe and wherein the interior surfaces of said annular valley portions are crowned and the wall thickness of the medial areas of said annular valley portions is greater than any other wall portion of the corrugations of the pipe, and wherein the ribs and valley portions per foot are each about 17 in number, the majority of said annular ribs being uninterruptEd and successively arranged in spaced groups with an interrupted rib between adjacent groups, each interrupted rib comprising a set of three interconnected circularly arranged spaced apart arcuate rib segments correspondingly arranged throughout the pipe, and one rib segment of each set being substantially longer than the other two rib segments and having an arcuate extent of at least 180*, the other two rib segments being of substantially equal length.

Claim 3

A corrugated resilient plastic drainage pipe according to claim 1, wherein said ribs are wider than said valley portions interconnecting the same and wherein the height of said ribs is also greater than the width of the valley portions.

Claim 4

A corrugated resilient plastic drainage pipe according to claim 1, wherein the wall thickness of the medial areas of said annular valley portions is of about 0.055 inch.

Claim 5

A corrugated resilient plastic drainage pipe according to claim 1, wherein relatively small annular reinforcing beads are provided along opposite sides of each of said annular ribs closely adjacent the periphery thereof.

Claim 6

A corrugated resilient plastic drainage pipe according to claim 1, wherein the interior diameter of the pipe is approximately 4 inches and the exterior diameter is approximately 4 1/2 inches and wherein the peripheries of the annular ribs are crowned.

Claim 7

A corrugated resilient plastic drainage pipe according to claim 1, wherein a series of three drainage holes are provided between said rib segments of each set with the diameter of the holes being greater than the width of the ribs, two of said drainage holes being positioned between the opposite terminal ends of said long rib segment and the respective shorter rib segments, the third drainage hole being positioned between the shorter rib segments and being substantially centrally disposed between said two holes, and means extending longitudinally of said pipe along the outer surface thereof directly opposite said third drainage holes for visually aiding in installing the pipe in the ground with all of the drainage holes located below the horizontal centerline of the pipe and the third drainage holes occupying lowermost position.

Claim 8

A corrugated resilient plastic drainage pipe having a compressive strength of at least 1,000 pounds per linear foot and being of lightweight construction of a plastic material having a density within the range of about 0.954 to 0.957 gm/cm3 with a wall thickness no greater than about one-sixtheenth inch, said pipe having spaced apart successively arranged annular ribs with interconnecting annular valley portions therebetween defining corrugations along the periphery of the pipe and wherein the interior surfaces of said annular valley portions are crowned and the wall thickness of the medial areas of said annular valley portions is greater than any other wall portion of the corrugations of the pipe, and wherein the ribs and valley portions per foot are each about 17 in number, the majority of said annular ribs being uninterrupted and successively arranged in spaced groups of five with an interrupted rib between adjacent groups, each interrupted rib comprising a set of three interconnected circularly arranged spaced apart arcuate rib segments correspondingly arranged throughout the pipe, and one rib segment of each set being substantially longer than the other two rib segments and having an arcuate extent of at least 180*, the other two rib segments being of substantially equal length.

Claim 9

A corrugated resilient plastic drainage pipe having a compressive strength of at least 1,000 pounds per linear foot and being of lightweight construction of a plastic material having a density within the range of about 0.954 to 0.957 gm/cm3 with a wall thickness no greater than about one-sixtheenth inch, said pipe having spaced apart successively arranged annular ribs with interconnecting annular valley portions therebetween defining corrugations along the periphery of the pipe and wherein the interior surfaces of said annular valley portions are crowned and the wall thickness of the medial areas of said annular valley portions is greater than any other wall portion of the corrugations of the pipe, and wherein the ribs and valley portions per foot are each about 17 in number, the majority of said annular ribs being uninterrupted and successively arranged in spaced groups of five with an interrupted rib between adjacent groups, each interrupted rib comprising a set of three interconnected circularly arranged spaced apart arcuate rib segments correspondingly arranged throughout the pipe, and one rib segment of each set being substantially longer than the other two rib segments and having an arcuate extent of at least 180*, the other two rib segments being of substantially equal length.

Claim 10

A corrugated resilient plastic drainage pipe according to claim 7, wherein the interior diameter of the pipe is approximately 4 inches and the exterior diameter of the pipe is approximately 4 1/2 inches, and wherein the pipe weighs no more than about 6 ounces per linear foot.

Claim 11

A corrugated resilient plastic drainage pipe according to claim 7, wherein the wall thickness of the pipe is within the range of about 0.043 to 0.055 inch and the plastic material is polyethylene.

Claim 12

A corrugated resilient plastic drainage pipe according to claim 7, wherein the pipe weighs no more than 5 1/2 ounces per linear foot and wherein the plastic material is polyethylene having a density of 0.955 gm/cm3.

Claim 13

A corrugated resilient plastic drainage pipe according to claim 7, wherein said ribs are wider than said valley portions interconnecting the same and wherein the height of said ribs is also greater than the width of the valley portions.

Claim 14

A corrugated resilient plastic drainage pipe according to claim 7, wherein a series of three drainage holes are provided between said rib segments of each set with the diameter of the holes being greater than the width of the ribs, two of said drainage holes being positioned between the opposite terminal ends of said long rib segment and the respective shorter rib segments, and the third drainage hole being positioned between the shorter rib segments and being substantially centrally disposed between said two holes.

Claim 15

A corrugated resilient plastic drainage pipe having a compressive strength of at least 1,000 pounds per linear foot and being of lightweight construction of a plastic material having a density within the range of about 0.954 to 0.957 gm/cm3 with a wall thickness no greater than about one-sixteenth inch, said pipe having spaced apart successively arranged annular ribs with interconnecting annular valley portions therebetween defining corrugations along the periphery of the pipe and wherein the interior surfaces of said annular valley portions are crowned and the wall thickness of the medial areas of said annular valley portions is greater than any other wall portion of the corrugations of the pipe, and wherein the ribs and valley portions are approximately six in number per each 4 inches of pipe length, five of said six annular ribs being successively arranged in a group with an interrupted rib adjacent one end of the group, each interrupted rib comprising a set of three interconnected circularly arranged spaced apart arcuate rib segments correspondingly arranged throughout the pipe, and one rib segment of each set being substantially longer than the other two rib segments and having an arcuate extent of at least 180*, the other two rib segments being of substantially equal length.

Claim 16

A corrugated resilient plastic drainage pipe having a compressive strength of at least 1,000 pounds per linear foot and being of lightweight construction of a plastic material having a density within the range of about 0.954 to 0.957 gm/cm3 with a wall thickness no greater than about one-sixteenth inch, said pipe having spaced apart successively arranged annular ribs with interconnecting annular valley portions therebetween defining corrugations along the periphery of the pipe and wherein the interior surfaces of said annular valley portions are crowned and the wall thickness of the medial areas of said annular valley portions is greater than any other wall portion of the corrugations of the pipe, and wherein the ribs and valley portions are approximately six in number per each 4 inches of pipe length, five of said six annular ribs being successively arranged in a group with an interrupted rib adjacent one end of the group, each interrupted rib comprising a set of three interconnected circularly arranged spaced apart arcuate rib segments correspondingly arranged throughout the pipe, and one rib segment of each set being substantially longer than the other two rib segments and having an arcuate extent of at least 180*, the other two rib segments being of substantially equal length.

Claim 17

A corrugated resilient plastic drainage pipe having a compressive strength of at least 1,000 pounds per linear foot and being of lightweight construction with a wall thickness no greater than about one-sixteenth inch and weighing no more than about 6 ounces per linear foot, said pipe having spaced apart successively arranged annular ribs with interconnecting annular valley portions therebetween defining corrugations along the periphery of the pipe and wherein the interior surfaces of said annular valley portions are crowned and the wall thickness of the medial areas of said annular valley portions is greater than any other wall portion of the corrugations of the pipe, and wherein the ribs and valley portions per foot are each about 17 in number, some of said ribs being interrupted and comprising a set of three interconnected circularly arranged spaced apart arcuate rib segments correspondingly arranged throughout the pipe, and one rib segment of each set being substantially longer than the other two rib segments and having an arcuate extent of at least 180*, the other two rib segments being of substantially equal length.

Claim 18

A corrugated resilient plastic drainage pipe having a compressive strength of at least 1,000 pounds per linear foot and being of lightweight construction with a wall thickness no greater than about one-sixteenth inch and weighing no more than about 6 ounces per linear foot, said pipe having spaced apart successively arranged annular ribs with interconnecting annular valley portions therebetween defining corrugations along the periphery of the pipe and wherein the interior surfaces of said annular valley portions are crowned and the wall thickness of the medial areas of said annular valley portions is greater than any other wall portion of the corrugations of the pipe, and wherein the ribs and valley portions per foot are each about 17 in number, some of said ribs being interrupted and comprising a set of three interconnected circularly arranged spaced apart arcuate rib segments correspondingly arranged throughout the pipe, and one rib segment of each set being substantially longer than the other two rib segments and having an arcuate extent of at least 180*, the other two rib segments being of substantially equal length.