flangevalid - Gasket selection

Gasket selection

taking into account the law, directives and sets of rules 1.0
Place of installation [Info]
Flanges/Apparatuses
Fitting
Pump
Storage life [Info]
Pressure [Info]
(flat sealing strip)
Regulations
Laws
Sets of rules
Resistance to media [Info]
Use in gas supply installations and oxygen plants [Info]
Food and pharmaceuticals approval [Info]
Conditions
Temperature [Info]
Surface pressure [Info]
[MPa(N/mm2)]
Material

This selection is informal, relates to the latest technology, and any guarantee is excluded.

Gaskets are safety-relevant components and must fulfill the requirements placed on them reliably and over the long term. The selection of gaskets according to this program puts the user in a position to select a gasket that reliably meets the requirements, taking into account legislation, directives and sets of rules. Please note the philosophy and the technical company philosophy of flangevalid.

It should be noted that conventional gasket profiles, which enable laws, requirements and directives to be complied with accordingly, are listed. Any possible inadequate quality of the gaskets from individual manufacturers cannot be taken into account here and must be checked by the user.

In addition to standard sizes for dimensioning purposes, the gaskets should be thoroughly marked with manufacturers’ logos, material reference numbers, date of expiry and, if applicable, with batch identification.

Notes:

Guideline 7/23: as requirements of gaskets, in 2003 it was accepted by both work groups:

"The main function of a gasket is to ensure tightness. Its material needs to fulfill only the relevant requirements of sections 4.1, 4.2 (a) and the first paragraph of 4.3."

Requirements of sections 4.1, 4.2 (a) and the first paragraph of 4.3 that gaskets have to fulfill:

- They must be adequately resistant.

- Chemical and physical properties must not be impaired during its service life. The manufacturer of the pressure equipment defines necessary values and properties of the materials with regard to section 2.2.3 and how the materials are treated with regard to 4.1.

- The manufacturer must take suitable measures to ensure that the material meets the specified requirements.

- In particular, documents issued by the material manufacturer to certify that the materials comply with a given regulation must be collected for all materials.

Note:

A selection is made according to the gaskets usually applied in these situations. As regards maximum application with maximum pressure, please take note of the poster Limitations for gaskets by pressure and flange design.

Note:

The highest and lowest temperature for operating the gasket joint should be entered.

Notes:

TRBS are technical rules for operational safety in terms of the German Federal Occupational Safety Directive (BetrSichV).

In order to have the status of a permanent technically tight joint, and hence no regular checks as with technically tight joints, according to TRBS 2141-3, an inner flange is necessary for gaskets made of flat gasket plate material at pressures over 25 bar.

Corrugated, spiral and grooved gaskets are special gaskets according to the TRBS and fulfill the requirements.

Notes:

Installations must be technically sealed, VBG 61 still required permanently technically sealed.

Notes:

TRBS are technical rules for operational safety in terms of the German Federal Occupational Safety Directive (BetrSichV).

In order to have the status of a permanent technically tight joint, and hence no regular checks as with technically tight joints, according to TRBS 2152-2, an inner flange is necessary for gaskets made of flat gasket plate material at pressures over 25 bar.

Corrugated, spiral and grooved gaskets are special gaskets according to the TRBS and fulfill the requirements.

Note:

The HTR approval (HTR=High-Temperature Resistance) is carried out according to DVGW-VP 401 by the Karlsruhe DVGW test laboratory.

Note:

According to Guideline 7/23 of the PED, the gaskets must ensure tightness, they must be adequately chemically resistant to the fluids, the required chemical properties must not be impaired during the intended service life, they must not be impaired by aging, they must not have any adverse interaction with the other materials in the joint, the manufacturer of the pressure equipment (here also the user) must take the appropriate measures to ensure that the material used meets the specified requirements - in particular, documents issued by the material manufacturer to certify that the materials comply with a given regulation must be collected for all materials.

Note:

The choice of gaskets only permits gaskets that fulfill the TA-Luft. The gasket manufacturer must provide a form of verification, usually a certificate with the inspection document. Please bear in mind that certificates without an inspection document are invalid (see note on the certificate).

Note:

The gasket must fulfill the requirements of having a permanent technical seal. Only high-quality gaskets are permitted. Gaskets with a potential hazard e.g. risk of injury or that need to be retightened after heating due to setting/flowing (dangerous procedure) are taken out.

Note:

The gasket must not be able to be pushed out of its place. Regulation in VDI 2200.

Notes:

TR = technical rule

AD = AD 2000 Code

UVV = Accident Prevention Guidelines

VA = Administrative instructions

Note:

According to the TRFL (Technical Rules for Pipelines), the manufacturer of the gasket must confirm the resistance to media in writing.

Note:

Elastomers and elastomer-bonded gaskets have a limited storage life (ISO 2230)

Note:

The resistance needs to be verified by the manufacturer and a certificate with inspection document provided. Please bear in mind that certificates without an inspection document are invalid (see note on the certificate).

Note:

The gasket manufacturer must present a valid inspection document issued by an institute. The selection is restricted to gaskets that normally have the appropriate approval.

Note:

The gasket manufacturer must present a valid inspection document issued by an institute. The choice is restricted to gaskets that normally have the appropriate approval.

Note:

The choice of gasket only permits gaskets that are permitted for the given pressures according to the appropriate standards (e.g. EN 1514).

Note:

A surface pressure worked out by a calculation for a gasket joint can be used as a selection criterion. The choice of gasket is limited to gaskets that can also withstand a surface pressure selected accordingly.

Warning:

Gaskets made of or with PTFE are hazardous waste and must therefore be disposed of separately! Information can be found on the manufacturer’s safety data sheet.

Note:

Asbestos-free elastomer-bonded fiberboards in accordance with DIN 28091-2.

Note:

PTFE gasket sheets in accordance with DIN 28091-3.

Note:

Graphite gasket sheets in accordance with DIN 28091-4.

Note:

Please mark the applicable points. The program selects the appropriate gaskets taking the requirements into account.

Note:

The resistance to media needs to be verified and confirmed by the manufacturer according to certain sets of rules.

Resistance to media is a very complex subject. It is best to consult the published lists, e.g. from DECHEMA. If only a conditional resistance for a sealing material is shown in these lists, this cannot be used according to the rules of the Pressure Equipment Directive (97/23/EC - PED).