| The Relief Cut |
| A Relief Cut, sometimes termed and "Arcuate Cut" was originally used to relief pressure on a turn-of-the-century gate valve. The same principle works well on a ball valve, especially when particulates are involved. The 24" copper mining valve being loaded above will benefit from this feature as will other mining and petrochemical applications involving slurries, catalysts, dry abrasives and muds. |
Copeland
Severe Service Ball Valves
Severe Service Ball Valves
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| Closed |
| Opening |
| Open |
A relief cut is an option Copeland uses when
manufacturing valves involving slurries and larger valves
with high pressure drops. A small section is taken out of
the leading edge of both ports of the ball (press on
thumbnail to view details).
This option helps in two ways:
1. It relieves pressure faster when
the ball first starts to open. This helps
protect the sealing surface and
prevents "wire line draw" from
eating away at the ball and seat.
2. The sharp edge of the
valve has been removed and the
coating covers more of a flat surface.
This prevents the lip of the ball from
catching on a foreign object and
damaging the coating.
manufacturing valves involving slurries and larger valves
with high pressure drops. A small section is taken out of
the leading edge of both ports of the ball (press on
thumbnail to view details).
This option helps in two ways:
1. It relieves pressure faster when
the ball first starts to open. This helps
protect the sealing surface and
prevents "wire line draw" from
eating away at the ball and seat.
2. The sharp edge of the
valve has been removed and the
coating covers more of a flat surface.
This prevents the lip of the ball from
catching on a foreign object and
damaging the coating.
