Pre insulated PE-100 Pipes

Dears,
Can any one guide me what is the advantage of pre insulated poly ethylene (PE-100 pipes) in chilled water underground piping. How the joints are making . Is there pre insulated fittings are available. Your advice will be very Helpfull in this regards Jamal
Al Khobar
<a href="/group/PipingDesign/post?postID=ApkW3IYvsn7sNrbogKuiDds0EhdDJ4IOozf0vW9H8IYzMkjowoEj4WY8JzN462f1oE0f9Ybk6JzsK__1pw">jamalmkc@gmail.com</a>,<a href="/group/PipingDesign/post?postID=lmMpuoPjL63Ta7kt1pNFVvCWQAG7MJMJWH5xL6NvNWXwtUClyDXrxaZD9jlXsWwHx62YjvDkXEcJ7HqKEQ">jamalmkc@yahoo.com</a> Received on Thu Nov 08 02:38:00 2007