Wear monitoring construction for erosive/corrosive flow conducting devices

Claim 1

A wear monitoring apparatus comprising: a. a body having an exterior surface; b. a body interior surface defining therewithin a flow annulus that comprises upstream and downstream bore sections; c. a means mounted within said flow annulus for controlling flow in the flow annulus; d. a seat means having a central longitudinal bore, said longitudinal bore coinciding generally with a portion of the bore section of the flow annulus, said seat means adapted to be received and removably mounted within the annulus; e. a first laterally extending port means through said body for providing fluid communication from the flow annulus through said body to the exterior surface of said body; f. first and second exterior seal means for isolating a section of the flow annulus between said body and said seat means that communicates with said first port means, said first exterior seal means being positioned upstream of said first port means, said second exterior seal means being positioned downstream of said first exterior seal means, said first and second exterior seal means and said first lateral port means thereby defining a monitoring window; g. a longitudinally extending liner removably mounted coaxially in the central bore of said seat means for monitoring wear; h. first and second liner seal means positioned at opposite end portions of said liner means for providing a sealed void space of monitored length between said first and second liner seal means that can collect and isolate fluid leakage caused by flow cutting through said liner means; and i. a second laterally extending port means extending through said seat means in communication with said first port means for transmitting flow between said first port means and the sealed void space of monitored length.