English (language) A castle is a fortress. It may also have a residence, and many castles were residences of various lords and nobles, but a castle isn't required to be a residence, as many were built to be forts guarding militarily interesting areas. A mansion is a large, opulent residence. It may have a fairly high degree of security and some level of fortification to protect the people living there, but it is not intended to be a strong place with strategic military importance. Written Jun 12, 2015 â¢ View Upvotes.
A plug weld is used to fasten two pieces of metal together using a welder. When joining the pieces, a hole is drilled into the top piece and it is laid over the bottom one. A weld is then made by running a bead inside of the drilled hole, thereby holding the two pieces together.
From Wikipedia, the free encyclopedia. In fluid mechanics, plug flow is a simple model of the velocity profile of a fluid flowing in a pipe. In plug flow, the velocity of the fluid is assumed to be constant across any cross-section of the pipe perpendicular to the axis of the pipe.he plug flow model has many practical applications. One example is in the design of chemical reactors. Essentially no back mixing is assumed with plugs of fluid passing through the reactor.