fig1 in one specific embodiment expandable casing 30 is disposed within well 20 that has been drilled into formation 26 well 20 is defined by well inner wall surface 22 expandable casing 30 has upper end 32 lower end 34 bore 36 defined by inner wall surface 38 outer wall surface 39 and axis 40 expandable casing 30 includes run in diameter 42 set diameter 44 and transitional diameter 46 run in diameter 42 is less than set diameter 44 and transitional diameter 46 illustrates the location of a cone not shown or other device used to expand expandable casing 30 from the run in diameter 42 to the set diameter 44 although a cone is described as being used to expand expandable casing 30 from the run in diameter 42 to the set diameter 44 it is to be understood that any device or method known to persons of ordinary skill in the art may be used to expand expandable casing 30 as illustrated in fig1 disposed on outer wall surface 39 of expandable casing 30 are upper sealing device 50 and lower sealing device 60 in this embodiment upper sealing device 50 is identical to lower sealing device 60 except that upper sealing device 50 is shown in the set position and lower sealing device 60 is shown in the run in position it is to be understood however that expandable casing 30 may have only one sealing device 50 60 or more than two sealing devices 50 60 for convenience both upper and lower sealing devices 50 60 will be discussed in greater detail with reference to like numerals sealing devices 50 60 include annular deformable sealing elements 51 having upper.