Drill pipe is in accordance with API SPEC 5D, it can be divided into two groups:
Group 1--Grade E drill pipe
Group 3--All high strength grades of drill pipe .(Grades X-95, G-105, S-135)

The minimum elongation in 2 in.(50.8mm) shall be that determined by the following formula:
"e=625,000A0.2/U0.9"
"e" = minimum elongation in 2 in (50.8 mm) in percent rounded to nearest 0.5%.
"A"= cross-sectional area of the tensile test specimen in square inches, based on specified outside diameter, or nominal specimen width, and specified wall thickness rounded to the nearest 0.01 in.2, or 0.75 in.2, whichever is smaller.
"U"= specified tensile strength, psi.

Note: See Table 5 in API SPEC 5D for minimum elongation values for various size strip tensile specimens and grades. The minimum elongation for either round bar tensile specimen (0.350-in. diameter with 1.4 -in, gauge length and the 0.500-in. diameter with 2.00-in. gauge length) shall be that shown in Table 5 for a cross-sectional area "A" of 0.20 in.2.

Tolerances on Dimensions
The following tolerance apply to the outside diameter of the drill pipe body immediately behind the upset for a distance of approximately 5 in. for sizes 5-1/2 and smaller, and a distance approximately equal to the OD for sizes larger than 5-1/2. Measurements shall be made with calipers or snap gages.

Inside Diameter: d, is governed by the outside diameter and weight tolerances.
Upset Dimensions: Tolerances on upset dimensions are given in Tables 7 and 8 in API SPEC 5D.
Eccentricity:
Outside Diameter: The maximum eccentricity, measured with a saddle gage (see Figure 5) at a distance of 5 to 6 in. from the end of the upset, shall not exceed 0.093 in. (total indicator reading).
Inside Diameter: The maximum eccentricity of the bore of the upset with respect to the outside surface of the drill pipe shall not be more than 1/16 in. (1/8 in. total indicator reading).
Ovality: Maximum ovality, measured with a micrometer on outside diameter of upset shall not exceed 0.093 in.