In the 1970's there was no such product as Non-asbestos gasketing. Asbestos was the product of the day and why not, it was effective, low cost and as long is it was handled properly it was safe.
In the 1980's asbestos became a dirty word, and for good reason it caused cancer. The problem was the baby got thrown out with the bath water. The asbestos in asbestos gasket material was embedded in the rubber it was blended with so, unless you took a grinder to the material to separate the asbestos out and then breathed in the asbestos (which could be avoided by oiling or wetting the material first), it was not going to hurt you. Even so, the lawyers got to work on it and effectively killed the industry. The only remaining manufacturing of asbestos gasket material is off shore. Today, very few distributors in the USA will carry it (including this one) most will only sell non-asbestos gasket materials. American Seal & Packing has never sold any asbestos product and only sells non-asbestos compressed gasket materials. Below are some of the other brands we offer.
Johns Manville took the biggest hit, once the largest distributor of gasket material in the Untied States (JM 60 was a standard), their liability was the worst since they also produced asbestos insulation. The asbestos fibers were easily released from insulation and easily breathed in. Johns Manville eventually declared Chapter 11 and sold off divisions. The gasket material division was later reformed as a portion of JM Clipper and no longer sold asbestos. The Gasketing division was sold off, but we still offer the new brand Leader Gasketing.
Leader Gasket maintains the same part numbers that JM Clipper established over the years. The most common Style numbers are:
NA-59 and NA60 - Both cutter grade sheets Both NBR/Armid based sheets, the difference is the temperature they will handle.
940 - A high tensile NBR Aramid sheet
960 An SBR/Aramid blend - SBR is ideal in steam and chemical applications and has excellent abrasion resistance.
978 and 978-C are NBR/Aramid sheets for hot oil, petroleum, and pulp and paper services to 700 F (Peak)
961 - An off white version of 960 to prevent color contamination.
986-A is an EPDM based compressed sheet material for more severe applications.
1080 An off-white NBR/Aramid sheet for general service applications.
In the 1980's the industry was prone. The first company to come out with a quality non-asbestos substitute and to market it well was Garlock. At the time Garlock was the number two seller of compressed asbestos gasket material (number 3 was Durabla Manufacturing). Garlock came out with their "Blue Guard" line and although it was not as good as asbestos in many applications it was better than a potential law suit. Before long Garlock was number 1. U.S. Gasket material customers were afraid of purchasing any asbestos containing product. With the exception of the Oil refineries.
Lamons Gasket Materials Include
Rubber and Fiber Sheet
Compressed Non-Asbestos Sheet
Virgin / Glass-Filled / PTFE Gasketing
Biaxially Orientated (Filled) PTFE Sheet
Expanded PTFE Sheet
EPTFE Joint Sealant
PTFE Envelope Gaskets
Flexible Graphite Sheet
Lamons Gasket Handbook
The refineries took their case to the supreme court and won the right to maintain the use of asbestos gasket material since no other product at the time was proven to be as effective. It did not make sense to protect workers from asbestos but not protect them from a failed gasket which in some applications (such as a steam line) can cause death. People have been cut in half by walking past a leaking steam flange due to gasket failure. The refineries won and continued to use asbestos until they finally found non-asbestos replacements. Durabla Manufacturing's "Durabla Black" is no longer produced. Production of Durabla Black ceased in 2012. Durlon Replaced Durabla's product line with non-asbestos Gasket Materials.
Durlon Gasket Material
Most of todays non-asbestos gasket materials contain either Kevlar, an aramid fiber, fiberglass, carbon, graphite or another mineral fiber. Todays major manufacturers include: Garlock, Gasket Resoures Inc., and Thermoseal (previously Klinger USA) . Most of the manufacturers are now producing off shore. Garlock produces sheet in Mexico and the USA for North American consumption. Gasket Resources Inc. produces in Canada, Thermoseal produces domestically in Ohio (USA) and Internationally. Sourcing of course is a dynamic situation and subject to change.
ThermoSeal / Klinger
Gasket Material StylesC-8200
Regardless of the manufacturer, the basics are the filler and the elastomer used. While no two compounds (or the % of filler) are identical, the basic Elastomers are: NBR (Buna-N), SBR, EPDM or Neoprene. If you examine which material you need (as defined by the application) and select the non-asbestos gasket material with that elastomer you will usually do well. This method will also allow you to select a competitive brand that will serve your application. No two materials are identical so caution must always be exercised. In general the common "Binders" are:
NBR - good for oils, gas, mild chemicals and water
SBR - good for saturated Steam, mild chemicals inert gas and water
Neoprene - good for saturated steam, refrigerants, oils, fuels, mild acids and alkalies and water.
EPDM - good for saturated steam, mild chemicals and water
Each material listed regardless of manufacture will indicate the "Binder" which makes cross referencing equal materials a much easier task. You should however pay attention to Tensile strength (for pressure resistance) Temperature ratings, and Compression / Recovery ratings.
You must also consider Size, Temperature, Application, Media, Pressure, Speed (if dynamic) of your specific application. If this is for a finished gasket you will also want to consider bolt loads, the size of bolts, the number of bolts, the bolt material and the available torque.
We at American Seal & Packing can assist you with a material selection of non-asbestos gasket materials or sell to you a non-asbestos gasket material on-line at ww.sealsales.com. We can also offer a number of non-asbestos gasket manufacturers products to meet your specifications.
Ph: 714-593-9780 Fax: 714-593-9701
Call American Seal & Packing for your gasket material requirements.