SOUNDOWN offers two basic high temperature thermal insulation systems, for use on hot exhaust pipes. Both systems use a non-asbestos, fiberglass blanket as the base insulation material. The standard blanket is flexible and has a thickness of 1". It withstands temperature in excess of l,2000F. The two systems differ in the type of covering over the fiberglass wool



Our plaster impregnated "rewettable" cloth forms an easily moldable covering to the fiberglass blanket, which becomes weatherproof and paintable after coating with our mastic sealant. This system is ideal for treating complex shapes and exposed pipes.


Procedure for applying:

1) Cut and fit fiberglass blanket. Wire in place with stainless or copper wire. (Keep surface as smooth as possible).

2) Cut rewettable cloth in strips.
Roll strips loosely.
Dip rolled strips briefly in warm water.
Apply strips over fiberglass (winding with a 50% overlap will give a double coat. Two or more coats are suggested).
Use gloved hands to smooth the soft plaster.
Let dry for approximately 24 hours.

3) Apply two coats of mastic, 50 ft2/gallon per coat, waiting 1 hour between coats. Allow to dry for 24 hours before painting.



The laced-on covering uses an aluminized fiberglass cloth cover which is assembled to the fiberglass blanket by crimped-on stainless steel lacing hooks and washers. These covers are then held in place by wire lacing. Straight pipe runs are easily treated with this system, but complex shapes generally require greater time and effort to achieve a good fit.


Procedure for applying:

1) Measure pipe segments, length and circumference (wrap a string around) of straight and elbow pieces. Add 6 "" to the pipe circumference to get the width, C, of 1", thick insulation needed to wrap the pipe.

2) Cut the fiberglass to width C, and of the appropriate length. For elbows, a butterfly pattern is required: check the fiberglass pieces for fit.

3) Cut the aluminized cover with 2 " to 3" excess beyond the edge of the fiberglass. (Use the fiberglass pieces as cutting guides.) Remember to cut the pieces for installation with the aluminized face outward.

4) Lay the aluminized cover over the fiberglass mat and wrap excess beneath. Push the lacing hooks through the cover and wool at 6" to 8" intervals along the "joint edges", the hooks should be 1 " to 2" from the edge of the fiberglass.


(The pipe wrap end may be finished in the same fashion as the edges and the hooks used to join sections of wrap together.)

5) Slide washer over the protruding lacing hook shank.

6) Crimp lacing hook shank using a piece of flattened 3/8" tubing, following the sequence illustrated below:

7) Install blankets by lacing lightly with thin gauge stainless steel or copper wire.