historical Colmonoy cooling process - asbestos use? 1

[mads2010]

Hello,

I am looking into the industrial process associated with annealing pump plungers. I would like to know how these materials were cooled -- quickly or slowly? In a vat of flame retardants (like asbestos)? Or a "tundle" (?) in which they might cool to room temperature? Or in a "tundle" associated with an air hose?

I would be appreciative of any information.

 

[unclesyd]

What little I recall about these materials is that they were always slow cooled. The parts were always cooled to RT.

We probably used one or all these methods.

Cooled in a closed furnace. The furnace had to have a high thermal mass to retard the cooling or the temperature could be ramped down.

After welding or brazing cooled by covering with slacked lime or vermiculite.

Wrapped in "A" cloth.

The last I remember seeing slow cooled Cerawool Ceramic fiber was used.

I don't every remember using any fibers. especially asbestos.

 

[mads2010]

Thanks so much!

>The parts were always cooled to RT
Can you estimate how much time this might take for a pump plunger?

>Cooled in a closed furnace
Do you recall if these furnaces were lined with an asbestos refractory material? Or if they were perhaps made of an asbestos-cement mixture?

>Wrapped in "A" cloth.
What is A Cloth?

 

[unclesyd]

Again recalling our plungers and some spargers were around 2" dia and it normally they were in the furnace overnight. Depending on your furnace or oven I think it would take minimum of five hours for a @" dia part.

The actual furnace lining was Hi-Temper Brick backed by insulating brick. Originally these furnaces had asbestos listing, rope, and asbestos paper incorporated as part of the lining. We went to Ceramic Wool on most furnaes and one with monolithic high Alumina lining.

"A" cloth is Asbestos cloth or lagging generally made from long fiber asbestos. The long fiber was not very friable.

 

[mads2010]

What time period were these practices (asbestos) customary? When were they phased out?

 

[unclesyd]

May I ask the reasoning for this line of questioning when it come to the cooling of Colmonoy?

Most everyone followed all the government directives from different branches.

 

[mads2010]

Not interested specifically in Colmonoy; rather, I am trying to figure out what potential asbestos exposures existed historically in the annealing process.

I really value your input - thank you so much!