Patent ID: 8875411

Claim:
A method of measuring parameters of a hollow pipe using a cylindrical ruler kit, the cylindrical ruler kit comprises a plurality of tubular members, each of the tubular members being an elongate, hollow, cylindrical tube open at both ends, the tube having an axial slit defined therein extending the length of the tube, the tube having a fixed, known diameter, each of the tubes having: a first indicia disposed on the tube marking the known diameter of the tube; a second indicia disposed circumferentially about at least one end of the tube, the second indicia marking the at least one end of the tube with a graduated circumferential scale indicating the circumferential distance around the at least one end of the tube; and a third indicia disposed lengthwise along the tube adjacent the axial slit, the third indicia marking the tube with a graduated ruled scale indicating the rectilinear distance along the tube, each of the tubular members having a different diameter, the tubular members telescoping within the largest diameter tubular member for compact storage and transport; the method comprising the steps of: inserting the pipe into the tubular members of progressively increasing diameter until a first matching tube having the closest fit of curvature to the pipe is found; reading the first indicia from the first matching tube to determine the outer diameter of the pipe; aligning the pipe with the ruled scale of the first matching tube and reading the axial length of the pipe; inserting tubular members of progressively increasing diameter into the pipe until a second matching tube having the closest fit of curvature to the pipe is found; and reading the first indicia from the second matching tube to determine the inner diameter of the pipe.