Ring Disc - N Range
The Goodwin ring disc design, the N range, is the standard closure member design for sizes 12” and larger in pressure classes ANSI 150# to ANSI 2500# and is available in 3 face-to-face lengths:
Type NK: Goodwin Standard Compact
Type NB: Goodwin Standard Long
Type ND: In accordance with API 6D
The Ring Disc design (12” and larger) ensures that the disc remains light and responsive even in large sizes. Mounted on a multiple helical spring and radial guide assembly, the disc moves freely without any of the frictional forces associated with the solid disc and shaft design. With a flow path both around and though the centre of the disc the flow capacity of the valve is best in class. Due to the excellent pressure recovery properties of the diffuser, the minimal pressure drop across the valves gives lifetime energy savings when compared to more conventional check valve designs.
The N range is suitable for all fluids subject to correct material selection and all installation positions.