O-RING KOORD NBR 6,00 MM

Product description:

• Round cords are extruded to length and have a round cross section (like an O-ring)
• After installation and compression in the installation chamber, the round cord achieves its sealing function due to the deformation of the cross section
• In operation, the medium pressure enhances the sealing function

Materials:

• NBR, NB 70
• FKM, FP 75
• EPDM (peroxide vulcanised), EP 70
• VMQ, SI 60

Colours:

• NBR 70, black
• FKM 75, black
• EPDM 70, black
• VMQ 60, red-brown

Tolerances:

• NBR, ISO 3302-1 E1
• FKM, ISO 3302-1 E1
• EPDM, ISO 3302-1 E1
• VMQ, ISO 3302-1 E2

Operating parameters:

• Temperature NBR: -30 °C to +100 °C
• Temperature FKM: -15 °C to +200 °C
• Temperature EPDM 70: -55 °C to +150 °C
• Temperature VMQ 60: -55 °C to +200 °C

Areas of application:

• Round cord rings usually serve as the base material for round cord rings and are similar in use to an O-ring
• Application takes place as a static seal, e.g. for sealing larger pipe joints and as a lid seal in reservoir construction
• Circular cords are often used for on-site repairs and are assembled 'to size' there
• Joining the ends of the pinion ring can be done by cyanoacrylate or 2-component adhesive, depending on the purpose of the application
• However, for use in seawater or other high-performance applications, a connection by vulcanisation is required

Standard material:

• NBR
  • NBR is the most commonly used material for O-rings due to its good mechanical properties and resistance to mineral oil-based lubricants and greases
  • These properties are largely determined by the acrylonitrile content (ACN between 18% and 50%)
  • Low ACN content leads to good cold-temperature flexibility but limited resistance to oils and motor fuels; with increasing ACN content, cold-temperature flexibility decreases and resistance to oils and motor fuels increases
  • Dichtomatik's NBR standard material for O-rings has a medium ACN content, covering a wide range of applications
  • This material possesses good mechanical technology values, e.g. high wear resistance , low gas permeability and good resistance to mineral-based lubricating oils and greases, hydraulic oils H, H-L, H-LP, flammable liquids HFA, HFB, HFC, aliphatic hydrocarbons, silicone oils and greases, water up to approx. 80°C
  • NBR is generally not resistant to aromatic and chlorinated hydrocarbons, motor fuels with a high aromatic content, polar solvents, glycol-based brake fluids and the flammable liquids HFD
  • NBR is less resistant to ozone, weathering and ageing
  • However, in the vast majority of applications this has no adverse effect

Assembly:

• During assembly, any damage to the O-ring should be avoided, otherwise leaks may occur
• In addition, the following advice should be observed:
  • The O-ring must not be stretched to its elongation limit
  • The edges must be burr-free, round sections and bevelled edges must be seamless
  • Dust, dirt, metal splinters and other particles must be removed
  • Sharp points of the thread and installation spaces for other seals and guide elements should be covered with mounting sleeve
  • Mounting surfaces and O-rings should be coated with a suitable grease
  • Heating in oil or hot water to approx. 80°C makes elastomers more flexible. The O-ring can therefore be stretched more easily for assembly
  • Any assembly tools such as assembly mandrels or sleeves should be made of soft material (e.g. POM) and have no sharp edges
  • The O-ring must not be rolled over the mounting surfaces. When mounted in the groove, the O-ring must not twist

Production of bonded RSR round cord rings:

• As standard, the pre-lengthened pinion rings are bonded with a cyanoacrylate adhesive (e.g. Loctite 406).
• The permissible temperature limit is approx. 80 °C
• In the case of EPDM, VMQ and FKM round cords, a special additional primer (e.g. Loctite 770) may need to be used
• Pay particular attention to the manufacturers' product information and safety instructions
• Before bonding, both ends should be roughened with fine sanding paper and degreased with a suitable cleaning agent (e.g. acetone)
• Both ends should be glued without tension
• Then check that the glued area is completely dry
• The glued cord ring may not be stretched over the area where the cord has been glued or vulcanised.
• The connection created in this way is clearly less elastic than the cord itself

Assembly instructions:

• During assembly, any damage to the round cord must be avoided, otherwise leaks may occur
• In addition, please observe the following instructions:
  • The bonded cord ring must not be stretched over the joint of the ends and the remaining part of the cord ring must not be stretched to the stretch limit
  • Chamfers should be burr-free, radii and bevels should be seamless
  • Dust, dirt, metals and other particles should be removed
  • Thread and installation spaces for other sealing and guide elements should be covered with mounting sleeves
  • Mounting surfaces and the pinion itself should be coated with a suitable grease
  • Heating in oil or hot water to approx. 80 °C makes elastomers more elastic
  • If necessary, assembly tools can be used. These tools should be made of soft material (e.g. POM) and have no sharp edges
  • The cord or cord ring must not be rolled over the mounting surfaces. When snapping into the groove, the cord ring must not rotate in the groove