What is the scope of application of API682 standard? Sealing system?

What is the scope of application of API682 standard? Sealing system?

1 Application field

The API682 specification is applicable to the sealing systems of centrifugal pumps and rotary pumps in the crude oil, natural gas, and chemical industries, and is widely used in hazardous, flammable, or harmful media conditions ranging from 20-110mm and their sealing shaft diameters. The sealing of other pumps, compressors, and mixers does not fall within the scope of this standard, but corresponding standards have been introduced. To achieve continuous operation of the pump, the sealing system of this standard should operate for at least 3 years (25000 hours)

2 Sealing System

The API682 specification divides sealing into three series, three forms, and three layout methods.

(1) Sealed series. API682 divides sealing into three series of applications: Series 1, Series 2, and Series 3.

(2) Sealed form. API682 categorizes seals into three forms: Type A, Type B, and Type C.

The application temperature for Type A and Type B closures is ≤ 176 ℃, and the application temperature for Type C closures is ≤ 400 ℃. B-type seals are commonly used in low-temperature conditions.

(3) Sealing layout method. API682 divides sealing into layout method 1, layout method 2, and layout method 3.

The preferred port combination mode for layout method 2 is the "reaction" combination mode, while the standard port combination mode for layout method 3 is the "reaction" mode, which allows the residue inside the sealed chamber to be ejected under centrifugal force, with little impact on the main seal, but the "back-to-back" and "zero distance" port combination modes are more compact.