Dope
Dope turns up in 2 fields: corrosion, aviation. Here is what it means to the people in each one.
Dope in corrosion
Pipeline slang for hot-applied coal tar or asphalt enamel coating, poured over the pipe and wrapped.
Pipeline construction word for the hot coal tar or asphalt enamel poured over pipe and wrapped with felt or glass mat. Crews talk of doping the pipe, the dope crew and the dope kettle, and plenty of big-inch lines in service carry dope. Aged dope gets brittle, can disbond and shield CP current, so digs on these lines often find corrosion hiding under the coating.
"This old line has dope on it, brittle as glass, go easy with the excavator or it'll shatter."
Dope in aviation
A specialized lacquer applied to fabric-covered aircraft to shrink, waterproof, and stiffen the material.
A liquid chemical coating, typically nitrocellulose or butyrate based, painted onto the fabric skins of older or lightweight aircraft. As it dries, it shrinks the fabric tightly across the airframe, adding structural rigidity and protecting the material from moisture and UV degradation.
"We need to brush on two more coats of dope before we can sand the fuselage."