A spade is a single solid blind, usually with a handle stamped with its size and class so it is visible from outside the joint. Spading a line means spreading the flanges, inserting the spade with new gaskets, and bolting up. It gives isolation that does not depend on any valve seat, which is why permits for vessel entry and hot work call for spades or spectacle blinds.
Spade the inlet and outlet before anybody goes in that drum, valves don't count for entry isolation.
Gulf Coast crews often call it a skillet; the handle is the giveaway that a blind is in the joint.
Also heard as
- paddle blind
- skillet
- slip blind
- blank
Related terms
Spectacle blind
A figure-8 shaped plate between two flanges with one solid end for isolation and one open ring for flow.
Double block and bleed
Isolation using two closed seats in series with a vent or drain between them to prove the isolation holds.
Bubble-tight
Shut off with no visible seat leakage when tested with air or gas under water.