Elastomer seals - donar.messe.de

SEAL TECHNOLOGY PREMIUM-QUALITY SINCE 1867

Elastomer seals for the pharmaceutical industry, food, bio and medical technology

Uncompromising premium quality: C. Otto Gehrckens – COG for short – has offered its customers first-rate quality for over 145 years. Tradition and innovation are a single potent entity at COG and the key to success. This is demonstrated daily in our customer relations. Our customers are among the best in their respective industries. And they expect no less from us.

COG has over 220 employees, all committed to the success of our customers – from the engineers in the Application Technology department to the quick off the mark colleagues at the world’s largest O-ring warehouse.

As an independent manufacturer based in Pinneberg near Hamburg in Germany COG has been family owned and managed for five generations. Today our high delivery capacity, our agile manufacturing capability as well as our committed customer service at all levels makes us a leading supplier of precision O-rings and elastomer seals.

Our customers define our goals in all our undertakings. From the close cooperation of Application Technology and Sales new ideas and products rapidly evolve both goal and market orientated – and with that creating a considerable market advantage for our cus-tomers. Let us discuss your aims!

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For the benefit of our customersWorld’s largest O-ring warehouse

For further information please

have a look at

www.COG.de or contact us

directly.

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• Founded in Pinneberg near Hamburg in 1867

• Independent family-owned company with more than 220 employees

• Optimised delivery service using our modern logistics centre

• Quality management per DIN EN ISO 9001 standards

• Environment management in compliance with DIN EN ISO 14001

• World’s largest O-ring warehouse

(more than 45,000 items kept in stock for immediate delivery)

• Tools available for more than 22,000 different O-ring dimensions

• In-house toolmaking

• Close cooperation with leading raw material manufacturers

• In-house compounding and compound development

• Release certificates and approvals available for various materials for the food and pharmaceutical industries (including FDA, USP, 3-A Sanitary Standard, BfR, KTW, DVGW, NSF/ANSI 61)

COG at a glance

ContentsOverview: material certificates of release and of approval ...... 5Overview compounds .............................................................. 6Correct choice of material ........................................................ 7WFI, SIP and CIP tried and tested materials ............................ 8EPDM/EPM materials ............................................................... 10Silicone/NBR/HNBR materials ................................................. 11FEPM/FKM materials ................................................................ 12Materials for the drinking water application ............................. 13Dairy pipe screw connection seals /clamp seals ..................... 14Hygienic Design/ Aseptic- screw connections ........................ 15Special material solutions ........................................................ 16Moulded parts and special services ........................................ 17Express production .................................................................. 18Stock and logistics ................................................................... 19

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Curiosity, experience, expertise.Three key COG attributes.

The use of seals in the biotech and medical technology fields as well as in the pharmaceuti-cal and the food processing industries makes it one of the most demanding application areas in seal technology. The seals used in these appli-cation areas have to meet special requirements which cannot be achieved by conventional seal materials e. g. because they have not met all approval certification prerequisites.

An overview of standards for the food and pharmaceutical industries

All the materials which come into contact with food being processed in production must com-ply with corresponding standards/approvals for use with foodstuffs. In addition to the materials approvals/standards such as FDA, EU Regula-tion 1935/2004, there are also construction requirements for the processing equipment relating to the installation spaces as well as the geometries of the individual parts.These include standards such as DIN 11864 for “aseptic screwed pipe connections” and DIN 11853 for “Hygienic flanged pipe connections”. For more information about these standards, see page 15.

Greater demands in production

The requirements for elastomer seals in the food and pharma-ceutical industries are becoming increasingly complex. As a result of the constant decreasing or even complete elimination of preservatives, cleaning processes have to use in a CIP (Cleaning in place) procedure to deal with contamination of pipes, valves, pumps etc. that occurs during the production process.

At the same time, it is apparent that production cycles are being shortened, with resulting increased productivity. Consequently, the cleaning process must also be shortened, and this is being achieved with even more aggressive CIP media. A good solution for production processes but a major challenge for sealing materials.

As a result of the constant decreasing or even complete elimina-tion of preservatives, dealing with the contamination of pipes, valves, pumps etc that occurs during the production process requires the constant improvement of the cleaning detergents.

The amount of preservatives used in the production process is constantly decreased or even completely eliminated. Therefore CIP procedures require constantly improved cleaning deter-gents in order to remove the contamination in the pipes, valves, pumps etc that occur during the production process.

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There are various standards applicable to the food and pharmaceutical industries and related sectors. Having the appropriate certification for materials used is indispensable in these application areas.

Release/Test certificate/Regulation Application/Country Criteria/Standards

BfR Recommendation(Federal Institute for Risk Assessment)

Plastics in contact with foodsCountry of origin: Germany

BfR regulations “Plastics coming into

contact with foods” Various sections depending on

use of seal element

NSF release (National Sanitation Foundation)

Food and sanitary facilitiesCountry of origin: USA

NSF standards and criteria

3-A Sanitary(3-A Sanitary Standard Inc.)

Materials for use in hygienic dairy and food

industry plantsCountry of origin: USA

3-A Sanitary Standards and criteria, Class I to IV

Food, medical and pharmaceutical industries

FDA regulation CFR 177.2600

(Food and Drug Administration)

Materials for use in food and pharmaceutical industries

Country of origin: USA

Including “White List” (list of formulated ingredients) as specified in

Federal Regulation 21. CFR 177.2600

USP certification(United States Pharmacopeia, USA)

Use in medicaland pharmaceutical industries

Country of origin: USA

Varying testing requirements:USP Class I to VI,USP Class 26…

Drinking water (no other use)

ACS approvalFrench Standard

NF XP P41-250, parts 1-3

Plastics in contact with drinking water

Country of origin: France

Testing of formulation based on “Synoptic Documents”

– storage test (microbe test)

DVGW Release for water

(German Association for Gas and Water)

Materials and components for drinking water: Seal materials for

drinking water plantsCountry of origin: Germany

DVGW W 534

DVGW W270 recommendation

(German Association for Gas and Water)

Materials in drinking water applications

Country of origin: Germany

Microbiologic testing; proliferation of micro-organisms on materials

KTW recommendationPlastics in drinking water; cold, warm and hot water

Country of origin: Germany

BfR regulations “Plastics coming into contact with foods

ÖNORM (Austrian Standards Institute)

Materials in contact with drinking water and warm water

Country of origin: Austria

Industry standards committee FNA 140 on water quality

WRAS release (Water Regulations Advisory Scheme)

Plastics in contact with drinking waterCountry of origin: Great Britain

British Standard BS 6920

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Overview of materialsby application areas

ASTM D1418 ISO1629 COG material Releases/approvals Page

Food technology

EPDM

AP 310 FDA 21. CFR 177.2600 10

AP 312 FDA 21. CFR 177.2600 10

AP 320 FDA 21. CFR 177.2600 10

AP 332 FDA 21. CFR 177.2600, KTW recommendation D2 10, 13

EPM EP 390 FDA 21. CFR 177.2600 10

FKM Vi 665 FDA 21. CFR 177.2600 12

HNBRHNBR 410 FDA 21. CFR 177.2600 11

HNBR 420 FDA 21. CFR 177.2600 11

NBR

P 581 FDA 21. CFR 177.2600, 3-A Sanitary Standard 11

P 582FDA 21. CFR 177.2600, KTW recommendation D2, DVGW DIN EN 549,

DVGW W 270, NSF/ANSI, WRAS BS 692011, 13

VMQ

Si 50 FDA 21. CFR 177.2600, BfR recommendation XV 11




Si 966, B FDA 21. CFR 177.2600, BfR recommendation XV 11

Si 973, R FDA 21. CFR 177.2600, BfR recommendation XV 11

Si 976, R FDA 21. CFR 177.2600, BfR recommendation XV 11

Si 976, TR FDA 21. CFR 177.2600, USP Class VI to +70 °C 11

Food, medical and pharmaceutical industries

EPDM

AP 302 FDA 21. CFR 177.2600, USP class VI to +121 °C, 3-A Sanitary Standard 8, 9, 10

AP 306FDA 21. CFR 177.2600, USP class VI Chapter 88 to +121 °C and Chapter 87,

ISO 10993 part 58, 9, 10

AP 313 FDA 21. CFR 177.2600, USP Class VI to +70 °C 10

AP 315 FDA 21. CFR 177.2600, USP Class VI, 3-A Sanitary Standard 10

AP 318FDA 21. CFR 177.2600, 3-A Sanitary Standard, KTW D1 and D2, DVGW

W 270 and W 534, DIN EN 681-1, NSF/ANSI Standard 61, WRAS BS 6920, ÖNORM B 5014-1

9, 10, 13

AP 323FDA 21. CFR 177.2600, USP Class VI to +70 °C, 3-A Sanitary Standard, KTW recommendation D1 and D2, DVGW W 270 and W 534, DIN EN 681-1, ACS,

NSF/ANSI Standard 61, WRAS BS 6920, ÖNORM B 5014-19, 10, 13

AP 372FDA 21. CFR 177.2600, KTW D1 and D2, DVW W 270 and W 534, DIN EN 681-1,

ÖNORM B 5014-1, WRC 4020, WRAS, NSF/ANSI 619, 10, 13

FEPM Vi 602 FDA 21. CFR 177.2600, USP Class VI to +121 °C 9, 12

FKMVi 780 FDA 21. CFR 177.2600, USP Class VI to +121 °C, 3-A Sanitary Standard 9, 10, 12

Vi 971, W FDA 21. CFR 177.2600, USP Class VI to +70 °C, 3-A Sanitary Standard 12

VMQSi 70, W FDA 21. CFR 177.2600, USP Class VI to +70 °C 11

Si 871, TRFDA 21. CFR 177.2600, USP Class VI to +37 °C, Chapter 87,

USP Class VI to +121 °C, Chapter 8811

Drinking water (no other use)

NBRP 480 KTW D1 and D2 13

P 520 KTW D1 and D2 13

It’s always better to talk to a professional. So why not contact our Application Technology department and take advantage of our expert knowledge!

+49 4101 50 02-964 e-mail: [email protected]

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Choosing the right materials for use in the food and pharmaceutical industries as well as in related areas is generally a major challenge. In addition to the required certification of materi-als, other factors must be taken into account. For, above all, the sealing materials employed must fulfil their primary purpose and provide a safe seal.

This is down to a fair amount of deciding fac-tors. In addition to their general effectiveness in sealing the media involved, interactions in for instance cleaning or sterilization processes, operating temperatures and mechanical prop-erties are only a few of the parameters that have to be taken into account.

To be absolutely safe, we urgently recommend a non-binding consultation with the applica-tions engineers. As a result of their years of experience and day-to-day confrontation with the various problems of our customers they are experts in choosing the right materials. In case an appropriate material cannot be assigned immediately our technicians will carry out the necessary research or advise you in the course of necessary tests of materials.

The right materialfor your application

Seal solutions for a wide range of applications

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Demands on the modern food industry are rising continuously as a result of constantly improved production processes. In addition to their general chemical resistance e. g. when used in fatty media or aromatic substances and essential oils, many elastomer seals have to applicable in CIP or SIP procedures (CIP = Cleaning in place; SIP = Sterilisation in place) commonly used today. Interactions between the media to be sealed off and the sometimes very aggressive disinfectant and cleaning agents or the superheated steam with a temperature of up to 149 °C used in the sterilization process are an enormous challenge for the materials. This constantly causes many elastomer seals to fail. More frequent main-tenance intervals, increased repairs, or even interruptions of production are the expensive consequences.

In cooperation with the firm Ecolab, one of the leading manufac-

turers of CIP media, COG has subjected three high performance seal materi-als for the food and phar-maceutical industries to extensive materials testing. In these tests Ecolab successfully

established the required predective properties of

the EPDM material AP 302, AP 306 and the FKM material

Vi 780 against various CIP media.

FD Water and WFI

FD water = fully desalinated water. WFI water = water for injection. WFI is absolutely pure water that has been completely demineralised. WFI strains and damages materials it comes in contact with by leaching out minerals, thus severely impairing them. In this way, WFI can for instance make concrete cavernous and thus unusable within a short period. VE water is an early stage of WFI, and is also used in production processes, although it is not as aggressive as WFI water. Both media strain elastomer materials enormously and only few seal materials can withstand and meet the requirements according to FDA and USP Class VI at the same time.

All three materials can easily be used in SIP procedures. In addition, the three compounds have also been tested successfully in aggressive WFI water at 90 °C, a medium increasingly used in the pharmaceutical industry.

CIP tested seals are absolutely essential when it comes to security for many design engineers and operators in the food and pharmaceutical industries.

AP 302 , AP 306 and Vi 780WFI water, CIP and SIP tested high performance seal materials

SIP inspected

WFI inspected

CIP inspected

The EPDM material “AP 302”, “AP 306” and the FKM material “Vi 780“ are specifically tailored to the food and pharmaceuti-cal industries and their extraordinary wide range of use in critical application areas. They are authorized for use accord-ing to FDA 21. CFR 177.2600 and USP Class VI, Chapter 88. In the USP test all materials were also successfully certified in the highest class up to 121°C.

The compounds “AP 302” and “AP 306” are exceptionally well suited for use with liquid media or media with low fat content. AP 302 offers excellent hardness of only 70 Shore compared to a very low compression set of only <12 % (22 h/100 °C). AP 306 has a hardness of 75 Shore A com-pared with a low compression set of <18 % (24 h/100 °C).

In case the fat content of the employed media is over 30 % it is advisable to use the seal material “Vi 780”. This seal material is also very resistant to aromatic substances and essential oils.

Seal solutions for a wide range of applications

In certain areas of application this high performance material achieves the sealing behaviour of FFKM seals, sometimes even exceeding it. Perfect prerequisites for use in highly demanding applications.

AP 318, AP 323 and AP 372 – when many authorizations are neededThese EPDM high performance materials meet a large num-ber of licensing requirements simultaneously. Three compact materials for variable use meeting diverse demands.

Material properties at a glance

ASTMD 1418

ISO1629COG-

number Hardness Colour Temperature range Special properties

EPDM

AP 302 70 Shore A black from -40 °C to +150 °C FDA, USP class VI to +121 °C, 3-A Sanitary Standard

AP 306 75 Shore A black from -40 °C to +150 °CFDA, USP Class VI Chapter 88 to +121 °C and Chapter 87, ISO 10993 part 5

AP 318 70 Shore A black from -35 °C to +140 °CFDA, 3-A Sanitary Standard, KTW D1 and D2, DVGW W 270 and W 534, DIN EN 681-1, NSF/ANSI Standard 61, WRAS BS 6920, ÖNORM B 5014-1

AP 323 70 Shore A black from -45 °C to+140 °CFDA, USP Class VI to +70 °C, 3-A Sanitary Standard, KTW D1 and D2, DVGW W 270 and W 534, DIN EN 681-1, ACS, NSF/ANSI Standard 61, WRAS BS 6920, ÖNORM B 5014-1

AP 372 70 Shore A black from -40 °C to +140 °CFDA, KTW D1 and D2, DVW W 270 and W 534, DIN EN 681-1, ÖNORM B 5014-1, WRC 4020, WRAS, NSF/ANSI 61

FEPM Vi 602 75 Shore A black from -10 °C to +230 °C FDA, USP Class VI to +121 °C

FKM Vi 780 80 Shore A black from -10 °C to +200 °C FDA, USP Class VI to +121 °C, 3-A Sanitary Standard

To meet the exceptionally high requirements of

the food and pharmaceutical industries, COG has

developed its HygienicSeal product line – the seal

of quality for safety.

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ASTMD 1418

ISO1629COG-


EPDM

AP 302 70 Shore A black from -40 °C to +150 °CFDA, USP class VI to +121 °C, 3-A Sanitary Standard

AP 306 75 Shore A black from -40 °C to +150 °CFDA, USP Class VI Chapter 88 to +121 °C and Chapter 87, ISO 10993 part 5

AP 310 70 Shore A black from -50 °C to +140 °C FDA


AP 313 70 Shore A white from -40 °C to +140 °C FDA, USP Class VI

AP 315 70 Shore A black from -40 °C to +140 °C FDA, USP Class VI, 3-A-Sanitary



AP 323 70 Shore A black from -45 °C to+140 °CFDA, USP Class VI to +70 °C, 3-A Sanitary Standard, KTW D1 and D2, DVGW W 270 and W 534, DIN EN 681-1, ACS, NSF/ANSI Standard 61, WRAS BS 6920, ÖNORM B 5014-1

AP 332 70 Shore A black from -50 °C to +140 °C FDA, KTW

AP 372 70 Shore A black from -40 °C to +140 °CFDA 21. CFR 177.2600, KTW D1 and D2, DVW W 270 and W 534, DIN EN 681-1, ÖNORM B 5014-1, WRC 4020, WRAS, NSF/ANSI 61

EPM EP 390 80 Shore A black from -40 °C to +150 °C FDA

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EPDM materialsAreas of application:Mainly food and the pharmaceutical industries.

Properties/Advantages:• Basic elastomer: Ethylene propylene diene rubber• Peroxidically or sulphur cross-linked• Good resistance in watery media• Good resistance in many CIP media• Good resistance to hot water and steam• Very resistant to ageing and ozone• Good low-temperature flexibility• Poor resistance to some plant and animal oils/fats

EPM materialsAreas of application:Various due to versatile material, also highly suitable for food-grade applications.

Properties/Advantages:• Basic elastomer: Ethylene propylene rubber• Peroxidically cross-linked• Good resistance in watery media• Good resistance to acids and alkalis • Good resistance in many CIP media• Outstanding resistance to hot water and water vapour• Limited resistance to some plant and animal oils and fats• Very resistant to UV, ageing and ozone• Good low-temperature flexibility

Widely used and proved

ASTMD 1418

ISO1629COG-


VMQ

Si 50 50 Shore A blue from -60 °C to +200 °C FDA, BfR

Si 70, W 70 Shore A white from -60 °C to +200 °C FDA, USP Class VI to +70 °C

Si 820 70 Shore A red from -60 °C to +200 °C FDA, BfR



Si 871, TR 73 Shore A transparent from -60 °C to +200 °CFDA, USP Class VI to +37 °C, Chapter 87, USP Class VI to +121 °C, Chapter 88

Si 966, B 65 Shore A blue from -60 °C to +200 °C FDA, BfR

Si 973, R 70 Shore A red from -60 °C to +200 °C FDA, BfR

Si 976, R 75 Shore A red from -60 °C to +200 °C FDA, BfR

Si 976, TR 70 Shore A transparent from -40 °C to +200 °C FDA, USP Class VI to +70 °C

NBRP 581 70 Shore A black from -40 °C to +120 °C FDA, 3-A Sanitary

P 582 70 Shore A black from -20 °C to +120 °CFDA, KTW D2, DVGW DIN EN 549, DVGW W 270, NSF/ANSI, WRAS BS 6920

HNBRHNBR 410 70 Shore A black from -20 °C to +150 °C FDA

HNBR 420 90 Shore A black from -20 °C to +150 °C FDA

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Silicone materialsAreas of application:Production processes of the food industry involving high temperatures.

Properties/Advantages:• Basic elastomer: Silicone rubber• Mostly peroxidically cross-linked• Physiologically inert• Limited mechanical properties• Weaknesses with some

acidic media• Weakness with SIP media• Excellent low temperature

flexibility

NBR materialsAreas of application:Food industry, especially in meat processing.

Properties/Advantages:• Basic elastomer: Acrylnitrile

butadiene rubber• Sulphur cross-linked• Good mechanical properties• Good resistance to oil and fat • Used in the meat processing

industry• Moderate resistance to many

CIP media• Not suitable for steam sterilization

HNBR materialsAreas of application:Production processes of the food industry involving high temperatures.

Properties/Advantages:• Basic elastomer: Hydrogenated

butadiene rubber (HNBR)• Peroxidically cross-linked• Good mechanical properties• Suitable for steam sterilization• Weaknesses with some

CIP media• Low gas and vapour

permeability

ASTMD 1418

ISO1629COG-


FEPM Vi 602 75 Shore A black from -10 °C to +230 °C FDA, USP Class VI to 121 °C

FKM

Vi 665 75 Shore A blue from -15 °C to +200 °C FDA

Vi 780 80 Shore A black from -10 °C to +200 °CFDA, USP Class VI to +121 °C, 3-A Sanitary Standard

Vi 971, W 75 Shore A natural white from -20 °C to +200 °C FDA, USP Class VI, 3-A Sanitary

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Materials containing fluorinefor demanding applications

FEPM MaterialsAreas of application:Highly demanding food and pharmaceutical industries applications

Properties/Advantages:• Basic elastomer: Viton® Extreme-ETP• Peroxidically cross-linked• Comparable with FFKM in certain areas, but

significantly cheaper• Application temperatures: -10 °C to +230 °C• Outstanding resistance in CIP/SIP procedures• Good resistance to essential oils, fatty and oily

substances, and aromatic substances• Good resistance to hot water and vapour• High chemical resistance

FKM MaterialsAreas of application:Highly demanding food and pharmaceutical industries applications

Properties/Advantages:• Basic elastomer: Fluoroelastomer rubber • Bisphenol cross-linked• Very good resistance to media• Hydrocarbons of all kinds (oils, fats, solvents)• Low gas permeability• Weakness with alkaline CIP media• Reasonable resistance to water vapour > 130 °C

ASTMD 1418

ISO1629COG-


EPDM


AP 323 70 Shore A black from -45 °C to +140 °C

FDA, USP Class VI to +70 °C, 3-A Sanitary Standard, KTW D1 and D2, DVGW W 270 and W 534, DIN EN 681-1, ACS, NSF/ANSI Standard 61, WRAS BS 6920, ÖNORM B 5014-1

AP 332 70 Shore A black from -50 °C to +140 °C FDA, KTW

AP 372 70 Shore A black from -40 °C to +140 °CFDA, KTW D1 and D2, DVW W 270 and W 534, DIN EN 681-1, ÖNORM B 5014-1, WRC 4020, WRAS, NSF/ANSI 61

NBR

P 480 70 Shore A grey from -20 °C to +120 °C KTW

P 520 70 Shore A black from -20 °C to +120 °C KTW

P 582 70 Shore A black from -20 °C to +120 °CFDA, KTW D2, DVGW DIN EN 549, DVGW W 270, NSF/ANSI, WRAS BS 6920

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Materials for drinking water approvalThe KTW (Drinking Water Commission) recommendation is a German drinking water ordinance by the German Federal Institute for Risk Assessment BfR (Bun-destinstitut für Risikobewertung previously BgVV). Products which are to be used in processing drinking water must satisfy the requirements and are tested for various properties. Among others, the effect of the product on the water quality, the release of components, and the necessity for disinfection.

Materials for drinking water applications

In addition to the KTW recommen-dation, the German Technical and Scientific Association for Gas and Water (Deutsche Vereinigung des Gas- und Wasserfachs (DVGW)) defines specific requirements for elastomers in drinking water in its working paper W270. According to these requirements, materials used in drinking water may not enhance the growth of microorganisms.

International RegulationsDifferent regulations frequently apply in other countries, such as the WRAS release or WRC approval for Great Britain, ACS approval for France, etc. In some cases, drinking water ap-proval in one country is also valid in other countries.

Our Application Technology department can provide you with more information.

Nominal size DN 10 15 20 25 32 40 50 66 80 100 125 150

Inner diameter 12 18 23 30 36 42 54 71 85 104 130 167

Outer diameter 20 26 33 40 46 52 64 81 95 114 142 155

Height 4,5 4,5 4,5 5 5 5 5 5 5 6 7 7

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Sealing rings for dairy pipe screw joints are applied in very different industries where they are subject to highest demands. The DIN 11851 standard for “Fittings for food, chemicals and pharmaceutical industry; stainless-steel screwed pipe connections” specifies the relevant dimen-sions, designs and materials for screwed pipe connections, often informally referred to as “dairy pipe screw connections” as well. Unlike many other screwed pipe connections, O-rings are not used as a seal element in dairy pipe screw connections, but instead a type G seal ring as shown in the illustration at the top right.

Clamp seals for clamp connectionsGerman standard DIN 32676 entitled: “Fittings for the food, chemical and pharmaceutical industries – Clamp connections for stainless steel tubes – Weld-on type” specifies requirements for “clamp connections”. Although this expression is not a standard expression, it is commonly used.

The following standard dimensions are produced:

Rings for dairy pipe screw and clamp connections

COG offers the following seal ring materials for dairy pipe screw or for clamp connections in compliance with DIN 11851 or DIN 32676: • EPDM: AP 310, AP 320; AP 302• EPM: EP 390• FKM: Vi 665, Vi 780• HNBR: HNBR 410 and 420• VMQ: Si 50, Si 820, Si 840, Si 870• FEPM: Vi 602

All materials have FDA or BfR approval (Federal Institute for Risk Assessment).

Nominal size DN * 10 15 20 25 32 40 50 65 80 100

Inside diameter 12 18 22 28 34 40 52 68 83 102

Cord thickness 3,5 3,5 3,5 3,5 5 5 5 5 5 5

* applies to pipes defined under DIN 11866 series A

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Pipe nominal size for the standards DIN 11853 and DIN 11864

In addition to dairy pipe screw connections and clamp con-nections, another trend is asserting itself in the food and pharmaceutical industries. The concept of “hygienic design” is gaining more and more importance in relation to food safety and product liability. Machines, plants and compo-nents in the food industry are supposed to be constructed and built according to “hygienic design”.

Hygienic design means designing parts, components and production plants with a focus on the cleansing processes. In the construction process the cleansing requirements are considered and areas avoided where dirt might concen-trate yet not be accessible for cleaning (e. g., CIP or SIP) and hence pose a risk to the product (for instance food). Effective and safe cleaning of production plants requires components that are easy to clean. Thus, hygienic design is an important element in safeguarding the quality of food, something which is becoming increasingly important.

Hygienic designAseptic screwed pipe connection German standard DIN 11864 entitled: “Fittings of stainless steel for the aseptic, chemical and pharmaceutical industry” is divided into three parts: 1. Aseptic screwed pipe connection 2. Aseptic flange connection 3. Aseptic clamp connection This standard uses the additional term “aseptic” to draw atten-tion to the fact that the materials referred to are used not only in the food industry but also in pharmaceutical. It involves very costly materials. In this standard, the term “material” refers exclusively to stainless steel, not to elastomers!

In addition, the standard DIN 11853 for “hygienic connections” is also of significance to hygienic design. The recommended seals used in modern hygienic design are mainly O-rings. The table below provides an overview of current O-rings in relation to tube sizes for the standards DIN 11853 and DIN 11864. In addition, there are two more tables for O-rings, but they are rarely used. If needed, these can be requested from our Application Technology department.

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PTFE PTFE is the abbreviation for the mate-rial polytetrafluoroethylene. This is a fully fluorinated polymer with unusually high melting viscosity. Thus, PTFE has tremendous thermal stability. Even if used persistently in demanding ap-plication environments with tempera-tures of 260 °C, this material remains fully usable after many thousands of hours. It is also resistant to almost all chemicals. Even aggressive acids such as aqua regia (nitrohydrochloric acid) cannot corrode PTFE. Moreover, PTFE has many further positive quali-ties, such as excellent electrical insula-tion and anti-adhesive behaviour, good dry-running properties and low heat conductivity. However, since PTFE is a very hard an inelastic material, there are restrictions in the applicability. Further-more PTFE cannot be elongated – a fact to be considered on assembly.

These outstanding features make the PTFE seal material of COG a univer-sally usable material for very different industries. As a result, PTFE is also used in the food, medical and pharma-ceutical industries.

COG is able to delivery directly from stock for many PTFE O-ring dimen-sions, and can thus offer rapid delivery.

FEP-encapsulated O-rings FEP-encapsulated O-rings offer two major benefits: very high resistance to a wide range of media while also offer-ing good elasticity. This is due to the 2-component system use in the design of these O-rings. FEP encapsulated O-rings have an elastic core made of silicone (VMQ). The coating of each elastic core consists of a seamless thin skin of FEP. This combination of out-standing resistance and good elastic-ity makes completely new application possibilities for these multi-component O-rings available. While the silicone O-ring offers the required elasticity, the FEP-coating protects the core against chemical media.

Customised material solutions

A recommended FDA material Good to know: FEP is an approved material (according to FDA Regulation 21 CFR 177.1550) for use in parts or components which come into contact with food and used for the production, processing, transport or storage of food.

In general, FEP-encapsulated O-rings with silicone core are available in thicknesses between 1.5 and 19 mm. FEP-encapsulated O-rings are used in many different chemicals, pharmaceutical and food-grade applications.

PFA – for extremely high temperatures In addition to FEP coatings, COG of-fers PFA coatings as well. PFA stands for perfluoroalkyl. PFA is used for coating silicone O-rings in the same way as FEP and has close to the same chemical resistance and the same properties as PTFE. Therefore, PFA-encapsulated O-rings can be exposed to higher working temperatures than FEP-encapsulated O-rings with the same low-temperature flexibility. The diagram below presents an overview of the operating temperature ranges.

Heat resistance and low-temperature flexibility of FEP- and PFA-encapsulated O-rings

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What many do not know is that in addition to our core precision O-ring business, COG produces moulded parts as well. The experience and expertise we have gained over decades working with elastomer seal materials we also put into the manufacturing of moulded parts. We can pro-duce rotationally symmetrical geometries based on customer drawings from almost all standard materials in lots of up to approx. 1,000 pieces. Our company’s own tool design and construction capability enables cost-effective production even

Special servicesIn addition to our extensive range of seal products, COG can offer a variety of special services. We have only listed a few keywords. Please contact our COG team for more information.

• Colour coding (dots) of O-rings• Primary and individual packaging• Subsequent cleaning in deionised water• Treatment removing all paint-wetting impairment substances (“LABS-free” condition)• 100% automated optical dimensional inspection (AD < 80 mm)• Special labels – also with customised bar coding• EDI connection• Certificate of compliance as per EN 10204 – 2.1• Certificate of compliance as per EN 10204 – 2.2• Inspection certificate as per EN 10204 – 3.1• VDA Initial Sample Inspection Report• Manufacturer’s certificate M as per DIN 55 350 part 18• Chamber of Commerce (IHK) certificate of origin for export• And many more custom services

In need of something special

for low-volume orders. The external diameter of the moulded parts manufactured must not exceed 1,400 mm. Moulded parts using rota-tionally symmetrical geometries include: flat seals, lip seals, profiled seal rings, dairy pipe screw connections, clamp connections, sealing collars, etc.

Please contact us directly to discuss the type of moulded parts we can produce for you!

Viton® is a registered trademark of E.I. du Pont de Nemours and Company

For further information please

have a look at

www.COG.de or contact us

directly.

EXPRESS SERVICE

* On certain occasions, such as plant holidays, special holidays or other in-house occurrences, our workdays may differ from

legal workdays. You can receive more information on this matter from our internal Sales department.

If worst comes to worse and no further delay is possible we at COG offer our customers an express production service. This special service is supposed to offer a loophole when caught in dire straits. We can produce those high quality precision O-rings not in stock within 5 to 7 workdays*. These orders are put onto the “fast lane” of our cleverly devised production processes and delivered in the shortest of times.

Especially for our express service we constantly have eight different, frequently used compounds in stock. These include FKM, FEPM, VMQ, HNBR, NBR and EPDM compounds. As long as ingredients are in stock, we can produce any other mixtures on request in this express manner. Do contact us if you need help!

COG–express productionWhen the pressure is on:

Express production essentials:• Production time between 5 and 7 work days*• 7 different compound mixtures constantly in stock• Max. quantity depends on the size of the O-rings • Express charge: 250 EUR flat, plus VAT

Deadline guarantee:If COG does not keep to the confirmed deadline for the express delivery you only pay the merchandise value.

** In workdays.

Quality Material Hardness in Shore A

Colour Properties Delivery time** on orders placed

before 10 a.m. after 10 a.m.

AP 310 EPDM 70 black FDA approval, peroxidically cross-linked 5 6

Vi 982 FEPM 75 black Excellent resistance to chemicals 6 7

Vi 500 FKM 80 black 6 7

Vi 564 FKM 70 black 6 7

Vi 665 FKM 75 blue FDA approval 6 7

P 583 NBR 70 black 5 6

Si 820 VMQ 70 red FDA and BfR approval 5 6

Delivery times for COG express production

External diameter in mm Maximum quantity

≤ 220 60

221 - 550 40

551 - 1400 25

Maximum quantity Simple procedures:Simply pay is the merchandise value of the O-rings plus express charge (€ 250,- plus VAT) – no minimum regard-ing quantity or value with this service

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One order, one delivery date,

one additional charge:

250 EURflat, plus VAT

COG is based in Germany – in the metropolis region of Hamburg, in close proximity to the Hamburg port and the international airport. Hamburg is known as “The Gate to the World”. And not without reason!

The easy access to all means of transportation and the possibilities therefore provided are strategically significant for our export activities.If necessary, we despatch orders that reach us before 3 p.m. the very same day all over the world. On request we deliver by courier “asap” – mostly even the next workday.

Distance is relative.Ordered and dispatched all over the world in one day.

An overview of the advantages of COG’s stock and logistics:

• Immediate availability for delivery• World’s largest O-ring warehouse

(more than 45,000 items kept in stock for immediate delivery)• State of the art storage and communication technology• If required, orders placed before 3 p.m. are dispatched the same day

provided parts are in stock• Storage provision for customers incl. call-off agreement for buffer-type storage• Overview of daily stock on hand at www.cog.de

For some of our customers that means: COG – so far away yet so close!

And from our point of view: distance is relative and close customer relation goes beyond borders.

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C. Otto Gehrckens GmbH & Co. KGSeal Technology

Gehrstücken 9 • 25421 Pinneberg • Germany

+49 4101 50 02-0

+49 4101 50 02-83

www.cog.de • [email protected]