O-RING GUIDE // ZATKOFF.COM Failure, improper selection or improper use of products or systems, the user, through his or her the products and/or systems described herein or own analysis and testing, is solely responsible related items may cause death, personal injury or for making the fi nal selection of the products and property damage. systems and assuring that all performance, safety and warning requirements of the application are met. This document and other information from Zatkoff Seals & Packings provides product and/or system The products described herein, including without options for further investigation by users having limitation, product features, specifi cations, designs, technical expertise. It is important that you analyze availability and pricing, are subject to change by all aspects of your application and review the Zatkoff Seals & Packings at any time. information concerning the product or system in the current product catalog. Due to the variety of operating conditions and applications for these OFFER OF SALE The items described in this document are hereby Copyright © 2019, Zatkoff Seals & Packings, offered for sale by Zatkoff Seals & Packings. This Farmington Hills, MI. All rights reserved. offer and its acceptance are governed exclusively by the provisions contained in Zatkoff Seals & Packings’ “Offer of Sale” located at www.zatkoff.com/terms. WARNING: These products can expose you to chemicals including carbon black (airborne and extracts), antimony trioxide, titanium dioxide, silica (crystalline), di(2-ethylhexyl)phthalate, ethylene thiourea, acrylonitrile, 1,3-butadiene, epichlorohydrin, toluenediisocyanate, tetra uoroethylene, ethylbenzene, formaldehyde, furfuryl alcohol, glass fi bers, methyl isobutyl ketone, nickel (metallic and compounds), lead and lead compounds which are known to the State of California to cause cancer; and 1,3-butadiene, epichlorohydrin, di(2-ethylhexyl)phthalate, di-isodecyl phthalate, ethylene thiourea, methyl isobutyl ketone, methanol, toluene, lead and lead compounds which are known to the State of California to cause birth defects and other reproductive harm. For more information go to www.P65Warnings.ca.gov. 2 O-RING GUIDE Table of Contents // ZATKOFF.COM Material Offering 4 Engineering Tools 27 Gland Designs 36 Sizing Charts 46 Metric O-Rings 64 O-Ring Kits 128 3 Material Offering Elastomers The basic core polymer of an elastomeric compound is called a rubber, produced eitherSynthetic Rubber as natural gum rubber in the wild, on commercial rubber plantations or manufactured Abbreviation synthetically by the chemical industry. Today, more than 32 synthetic rubbers are DIN/ISO ASTM Chemical Name 1629 D1418 known, the most important ones are listed on page 5. M-Group (saturated carbon molecules in main macro-molecule chain): Modern elastomeric sealing compounds generally contain 50 to 60% base polymerPolyacrylate Rubber ACM ACM and are often described simply as “rubber.” The balance of an elastomer compoundEthylene Acrylate — AEM consists of various fillers, vulcanizing agents, accelerators, aging retardants and otherChlo rosulfonated Polyethylene Rubber CSM CSM chemical additives which modify and improve the basic physical properties of the baseEthylene Propylene Diene Rubber EPDM EPDM polymer to meet the particular requirements of a specific application. Ethylene Propylene Rubber EPDM EPM Fluorocarbon Rubber FPM FKM Tetrafluorethylene Propylene Copolymer FEPM FEPM Elastomers used in producing seals, and particularly those used in O-rings, will usuallyPerfluorinated Elastomer — FFKM provide reliable, leak-free function if fundamental design requirements are observed. O-Group (with oxygen molecules in the main macro-molecule chain): “Cross-linking” between the polymer chains is formed during the vulcanization process, see “Schematic Representation of Polymer Chains Before and After Vulcanization.” Cross-linkingEpichlo rohydrin Rubber CO CO of the molecules changes the rubber from a plastic-like material to an elastic material. Epichlorohydrin Copolymer Rubber ECO ECO R-Group (unsaturated hydrogen carbon chain): After vulcanization, including any required “post-cure,” an elastomer compound attains the physical properties required for a good sealing material. As with all chemicalButadiene Rubber BR BR reactions, temperature is responsible for the speed of reaction. Only when the idealChlo roprene Rubber CR CR IIR IIR process temperature is constant during the entire vulcanization time, will the optimumIsobutene Isoprene Rubber (Butyl Rubber) Chlorobutyl Rubber CIIR CIIR degree of curing be reached. For this reason, the conditions of vulcanization are closelyIsop rene Rubber IR IR controlled and recorded as part of the Parker quality assurance process. Nitrile Butadiene Rubber NBR NBR Styrene Butadiene Rubber SBR SBR Introduction to Elastomers Hydrogenated Nitrile — HNBR Carboxylated Nitrile XNBR XNBR Before reviewing the available elastomers and their general properties, it is necessary to fully understand the terms “polymer,” “rubber,” “elastomer” and “compound” as they are used in this handbook. Q-Group (with Silicone in the main chain): Fluorosilicone Rubber FMQ FVMQ Methyl Phenyl Silicone Rubber PMQ PMQ Methyl Phenyl Vinyl Silicone Rubber PMVQ PVMQ Methyl Silicone Rubber MQ MQ Methyl Vinyl Silicone Rubber VMQ VMQ U-Group (with carbon, oxygen and nitrogen in the main chain): Polyester Urethane AU AU Polyether Urethane EU EU The Most Important Types of Synthetic Rubber, Their Elastomer Elastomer Groupings and Abbreviations no cross-links cross-linked Schematic Representation of Polymer Chains Before and After Vulcanization Polymer A polymer is the “result of a chemical linking of molecules into a long chain-like structure.” Both plastics and elastomers are classified as polymers. In this handbook, polymer generally refers to a basic class of elastomer, members of which have similar chemical and physical properties. O-rings are made from many polymers, but a few polymers account for the majority of O-rings produced, namely Nitrile, EPDM and Neoprene. 4 MATERIAL OFFERING Synthetic Rubber Abbreviation DIN/ISO ASTM Chemical Name 1629 D1418 M-Group (saturated carbon molecules in main macro-molecule chain): Polyacrylate Rubber ACM ACM Ethylene Acrylate — AEM Chlorosulfonated Polyethylene Rubber CSM CSM Ethylene Propylene Diene Rubber EPDM EPDM Ethylene Propylene Rubber EPDM EPM Fluorocarbon Rubber FPM FKM Tetrafluorethylene Propylene Copolymer FEPM FEPM Perfluorinated Elastomer — FFKM O-Group (with oxygen molecules in the main macro-molecule chain): Epichlorohydrin Rubber CO CO Epichlorohydrin Copolymer Rubber ECO ECO R-Group (unsaturated hydrogen carbon chain): Butadiene Rubber BR BR Chloroprene Rubber CR CR Isobutene Isoprene Rubber (Butyl Rubber) IIR IIR Chlorobutyl Rubber CIIR CIIR Isoprene Rubber IR IR Nitrile Butadiene Rubber NBR NBR Styrene Butadiene Rubber SBR SBR Hydrogenated Nitrile — HNBR Carboxylated Nitrile XNBR XNBR Q-Group (with Silicone in the main chain): Fluorosilicone Rubber FMQ FVMQ Methyl Phenyl Silicone Rubber PMQ PMQ Methyl Phenyl Vinyl Silicone Rubber PMVQ PVMQ Methyl Silicone Rubber MQ MQ Methyl Vinyl Silicone Rubber VMQ VMQ U-Group (with carbon, oxygen and nitrogen in the main chain): Polyester Urethane AU AU Polyether Urethane EU EU The Most Important Types of Synthetic Rubber, Their Elastomer Elastomer Groupings and Abbreviations no cross-links cross-linked MATERIAL OFFERING 5 Rubber Rubber-like materials first produced from sources other than rubber trees were referred to as “synthetic rubber.” This distinguished them from natural gum rubber. Since then, usage in the industry has broadened the meaning of the term “rubber” to include both natural as well as synthetic materials having rubber-like qualities. This handbook uses the broader meaning of the word “rubber.” Elastomer Though “elastomer” is synonymous with “rubber,” it is formally defined as a “high molecular weight polymer that can be, or has been modified, to a state exhibiting little plastic flow and rapid, nearly complete recovery from an extending or compressing force.” In most instances we call such material before modification “uncured” or “unprocessed” rubber or polymer. When the basic high molecular weight polymer, without the addition of plasticizers or other dilutents, is converted by appropriate means to an essentially non-plastic state and tested at room temperature, it usually meets the following requirements in order to be called an elastomer: A. It must not break when stretched approximately 100%. B. After being held for five minutes at 100% stretch, it must retract to within 10% of its original length within five minutes of release. Note: Extremely high hardness/modulus materials generally do not exhibit these properties even though they are still considered elastomers. The American Society for Testing and Materials (ASTM) uses these criteria to define the term “elastomer.” Compound A compound is a mixture of base polymer and other chemicals that form a finished rubber material. More precisely, a compound refers to a specific blend of chemical ingredients tailored for particular required characteristics to optimize performance in some specific service. The basis of compound development is the selection of the polymer type. There may be a dozen or more different ones to choose from. The rubber compounder may then add various reinforcing agents such as carbon black, curing or vulcanizing agents (such as sulfur or peroxide, activators, plasticizers, accelerators, antioxidants,