- weatherstrip seals for vehicle,door and window(sunlight,rainstorm, cold,wind,ozone,UV etc)
- edge trims for guard protection or rough parts decoration(e.g.sheet metal)
- sponge/foam rubber extrusions for anti impact/vibration/collision/hard-wearing
- industrial use rubber tubing,rubber extrusions profilesstrip/sheet,extruded large profiles
1.Raw material preparation–compounding
Mix all raw materials to a certain proportion except ultra accelerator and vulcanizator,for the first stage mixing:banbury internal mixing. Most of the rubber extrusions requires two stage mixing/plastication:- banbury internal mixing
- open mixing
2.Banbury internal mixing
Mix uniformly the crude rubber with the compounding ingredients e.g. vulcanizing agent,oil-softener,fortifier etc,and stash it for 8 hours or so,to make it- Recover the fatigue
- release mechanical stress
- Reduce shrinkage
- Compounding diffusing uniformly
- Bound rubber reinforcement between carbon black and rubber with cross-linking matrix structure
- One of the ingredients Kerosene is to change the plasticity and flexibility to be more machinable;
- The largest 3 synthetic rubber producing country are: USA/Japan/Korea,especially for EPDM rubber;
- Rubber straining machine can effectively wipe off the impurities of the compounding rubber
Open Mixing
Extruding
Vulcanization
Packaging (cutting or coiling)
Large size extruded rubber items are not easy to bend,it is more like straight bars,we often call them “rubber profiles”,rubber extrusions profiles are usually cut into centain length bars,such as anti-collision rubber profiles;
7.Or deep processing as per clients’ special requirement below:
- Hole punching
- Butt jointing
- Angle Adjancent
- Flocking/Pile coating
- Adhesive Backing
8.Required Properties for Automotive rubber extrusions
Working conditions of automotive rubber seals are required strictly conditional especially for weathering aspect,the service life of the finished product are up to the performance index of rubber extrusion items. Important parameters of automotive rubber extrusions:- Temperature range: typical value: -35℃ to 70℃
- Hardness
- Tensile strength: typical value >=7Mpa
- Enlongation at break Typical value 250~350
- Compression set(compression load)
- Anti-ozone aging
- Atmospheric aging
- Resistant to paint(coating properties)
- Low-temperature properties (low-temp elasticity) typical value:keep resilient at -35℃
- Installation performance(insert/pull out force)
- Flocking resistance
- Cohesiveness
- Extrusion force for edge trims
- Brittleness temperature typical value -35℃
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