1. A monitoring system for determining the status of a steam pipe, comprising: a programmable computer which when operating under control of a set of instructions recorded on a machine readable memory performs the steps of: controlling the emission of a probe ultrasonic signal having a frequency in the range of 2.25 Mega Hertz and above from an ultrasonic signal generator into a steam pipe; receiving from an ultrasonic signal receiver an electrical signal representative of an ultrasonic response signal which is generated in said steam pipe in response to said probe ultrasonic signal; processing said electrical signal by application of one or more of a filter, a moving average, a window, a transformation, a Shannon Energy Envelope and an autocorrelation method to produce a result representing a status of said steam pipe; and performing at least one of recording said result, displaying said result, and transmitting said result to another system.