Maintaining pipe wall temperature. Maintaining a constant temperature in a pipe wall in some hot process applications is critical. A new technique that utilizes bolt-on trace elements to maintain the temperature was presented in the Journal of Heat Transfer (Nov. 2000). Without bolt-on trace elements, the pipe wall temperature of a switch condenser used to produce plastic has a uniform distribution ranging from 260° to 290°F. When several bolt-on trace elements are attached to the piping, the wall temperature is uniform from 278° to 285°F.

a. Ideally, the pipe wall temperature should range between 280° and 284°F. What is the probability that the temperature will fall into this ideal range when no bolt-on trace elements are used? when bolt-on trace elements are attached to the pipe?

b. When the temperature is 268°F or lower, the hot liquid plastic hardens (or “plates”), causing a buildup in the piping. What is the probability of the plastic plating when no bolt-on trace elements are used?

when bolt-on trace elements are attached to the pipe?