Definition
Premium Class — Premium Class is a used-drill-pipe classification under API RP 7G-2 and DS-1 in which the tube retains at least about 80 percent of its nominal wall thickness with defined limits on cuts and damage, making it the standard grade for most drilling operations.
Also known as: premium class, premium class drill pipe, class 1 premium
What Premium Class means
Premium Class is a condition grade for used drill pipe defined by inspection standards such as API RP 7G-2 and DS-1. To be classified Premium, the tube body must retain a minimum remaining wall of about 80 percent of the nominal wall thickness, and any cuts, slip marks, corrosion pits or other damage must fall within the standard’s acceptance limits. Tool joints must also meet dimensional and MPI acceptance criteria.
Premium Class is the most commonly specified grade for drilling rental strings because it offers a strong balance of load capacity and availability. Its reduced-wall condition is accounted for in torsional, tensile and pressure ratings, which are derated from the new-pipe values accordingly.
How it is determined
- Remaining wall ≥ ~80% measured by EMI and confirmed with ultrasonics.
- Limited surface defects — cuts, gouges and pitting within class limits.
- Acceptable connections — tool joints gauged and MPI-inspected.
Pipe that falls below Premium limits but stays above the Class 2 threshold is downgraded rather than scrapped.
Why it matters for rentals
Specifying Premium Class and requiring the inspection certificates ensures you know the true capacity of your rental string. See our drill pipe and quality program, or contact us to confirm class and ratings.