With a need for periodic inspection or access to many hot insulated surfaces, removable/reuseable insulation covers have been found to be a good solution. These covers reduce the heat loss on surfaces such as valves, flanges, pumps, compressors, and piping where otherwise a permanent, non-reuseable type of insulation might be added. The use of removable covers can reduce the long-term cost of gaining access to the hot surfaces that need periodic inspection.
There are a number of different performance requirements encountered by removable insulation covers on hot surfaces. In general, the covers should insulate effectively, be capable of being easily removed and replaced, and last a certain period of time. An impediment to their durability is the conditions to which the blankets are exposed: high service temperature, leaking chemicals, sun and rain, physical abuse, and fire, among others. The selection of appropriate materials to meet the performance requirements of a particular job can be a difficult and complex task. Such a selection is generally addressed with specifications.
As as first step in developing removable insulation specifications, ASTM Committee C-16 on Thermal Insulation formed a task group to develop a standard guide. This document, which was balloted before Committee C-16 in late 1987 and received Society approval as ASTM C 1094 in 1988, identifies the performance issues faced by removable covers and their constituent materials. Being a guide, it does not recommend particular materials or even performance values. Rather, it recommends appropriate test methods, as well as general design and construction issues, that should be addressed by a specification. The use of ASTM C 1094 in developing removable cover specifications should ultimately improve the performance and quality of those covers.