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A question about elastomer 2
- Thread starter Johnae
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1
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EdStainless
Materials
Yes, you cna find it by web searching.
But the generic compound names are not the same materials. In elastomers the properties (especially aging and degredation) are closely linked to the fillers, cure agents, and additives that are used.
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Rust never sleeps
Neither should your protection
But the generic compound names are not the same materials. In elastomers the properties (especially aging and degredation) are closely linked to the fillers, cure agents, and additives that are used.
= = = = = = = = = = = = = = = = = = = =
Rust never sleeps
Neither should your protection
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1
- #3
Chemraz is a Greene Tweed product so you will find data on their web site. Kalrez is a DuPont product so look on their site. They are both FFKM (ASTM D1418) based elastomers.
Steve Jones
Materials & Corrosion Engineer
Steve Jones
Materials & Corrosion Engineer
- Thread starter
- #4
It depends what the individual manufacturers have blended into the final product.
Steve Jones
Materials & Corrosion Engineer
Steve Jones
Materials & Corrosion Engineer
The "Elastomeric Teflon" comes from the original introduction of Kalrez. This was used to introduce Kalrez to the public to convey the chemical resistance of the Teflon polymer used to compound Kalrez.
Adding to the statements above, the names Kalrez and Chemraz are trade names covering a family of compounds that exhibit very specific chemical compatibility and physical properties. In the Kalrez line there are about 8 compounds (1058, 6375, etc) and in the Chemraz line there are about 12 compounds (505,555,etc). This means that Kalrez will not always substitute for Chemraz and vice verse.
Unless you have very specific references the compatibility charts for any base materials are for relative pure fluids and should be used only as a starting point, especially if you have mixed fluids.
The selection of an Oring compound is a fairly complex task, much more than getting a black one off the shelf.
Anecdotal:
A changing an Oring compound cost my company over 8 million dollars due it's failure and the resultant explosion and fire.
We were using an EPDM Oring compounded to be nonconductive to seal a feed through on an electrolytic cell. The nonconductive Oring cost $2.35 each. Purchasing in their infinite wisdom found an EPDM Oring for $0.49. The conductive Oring allowed enough electric leakage through the feed through to heat the gland to where it failed. This leak to release of conductive liquid, highly flammable organics, Hydrogen and Oxygen.
Adding to the statements above, the names Kalrez and Chemraz are trade names covering a family of compounds that exhibit very specific chemical compatibility and physical properties. In the Kalrez line there are about 8 compounds (1058, 6375, etc) and in the Chemraz line there are about 12 compounds (505,555,etc). This means that Kalrez will not always substitute for Chemraz and vice verse.
Unless you have very specific references the compatibility charts for any base materials are for relative pure fluids and should be used only as a starting point, especially if you have mixed fluids.
The selection of an Oring compound is a fairly complex task, much more than getting a black one off the shelf.
Anecdotal:
A changing an Oring compound cost my company over 8 million dollars due it's failure and the resultant explosion and fire.
We were using an EPDM Oring compounded to be nonconductive to seal a feed through on an electrolytic cell. The nonconductive Oring cost $2.35 each. Purchasing in their infinite wisdom found an EPDM Oring for $0.49. The conductive Oring allowed enough electric leakage through the feed through to heat the gland to where it failed. This leak to release of conductive liquid, highly flammable organics, Hydrogen and Oxygen.
EdStainless
Materials
The other fluoropolymer based elstomer is Aflas. If you really want the best try Seals Eastern in Red Bank NJ.
If you are looking at using these materials then you know how expensive they are, and you must have a very critical application.
When I was buying elastomers we had a simple rule. We would qualify a specific formulation from each potential supplier, and they had to commit in writing that if they changed any ingedients (even just sources of the same material) they would have to requalify. period. no exceptions.
= = = = = = = = = = = = = = = = = = = =
Rust never sleeps
Neither should your protection
If you are looking at using these materials then you know how expensive they are, and you must have a very critical application.
When I was buying elastomers we had a simple rule. We would qualify a specific formulation from each potential supplier, and they had to commit in writing that if they changed any ingedients (even just sources of the same material) they would have to requalify. period. no exceptions.
= = = = = = = = = = = = = = = = = = = =
Rust never sleeps
Neither should your protection
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