API (American Petroleum Institute)

An industry organization that has written a set of pump standards. The standards cover the minimum requirements for sealing systems for centrifugal and rotary pumps supplied with:

  • Seal sizes from 1.5 to 4.5 inches (30 to 120 mm)
  • Stuffing box temperatures from -40°F to 500°F (-40°C to 260°C)
  • Stuffing box pressures from 0 psia to 515 psia (0 bar to 34.5 bar).

The standard is designed to default to the equipment types most commonly supplied that have a high probability of meeting the objective of at least three years of uninterrupted service while complying with emission regulations.

Seals supplied by a seal manufacturer are subject to the same requirements that apply to seals supplied by the original equipment manufacturer (OEM)

See: API Standard, What is wrong with it?



  • On February 14, 2018