Bullard offers fire helmets in a variety of materials, in order to suit the specific needs of each firefighting situation.
Composite helmet shells are a mixture of thermoset resins and glass fiber. The thermoset resin is the “glue” which is needed to hold glass fibers together in a composite helmet shell Thermoset resins are a family of plastics that do not melt but chemically degrade at high temperatures, and thermoset resins are aeated by mixing two base materials just like epoxy glues (Epoxy glues are thermoset resins). One of the ingredients is a catalyst that, when combined with the other agents and heat during molding, will solidify the mixture, locking itself and the glass fibers into a rigid state. In compression molding applications, very little catalyst is used so that the Liquid resin remains stable at room temperature; the heat and pressure of the molding operation initiates the chemical reaction to solidify the resin.
Thermoset resins by themselves have relatively little strength; the strength of a therrnoset composite material comes primarily from the fibers of glass or other materials that are bonded together by the resin.
The challenge in designing an effective composite material is getting the right mix of a good thermoset resin and high content of glass. The glass fiber is heavier than the resin, so getting the right mix also creates the best potential for a lighter helmet shell. Most fire helmets today have a glass content of approximately 50 percent.
High Performance Thermoplastics
Until relatively recently, it was possible to obtain either great heat resistance or great impact resistance, but not both in the same material. Thanks to new thermoplastic advancements, thermoplastics can now exhibit a high quality surface finish, impact resistance and heat resistance. While todays advanced thermoplastics can perform at temperatures exceeding 500″ F (260″ C), thermoplastics can be sensitive to some chemical solvents.
Vanguard Fire & Safety is a distributor of leading brand fire-fighting equipment and specialised industrial safety products. We are committed to the supply of premium quality products to the fire and emergency services related market and industrial safety segment.
We have an office in Port Elizabeth and one in Durban.
PORT ELIZABETH OFFICE: +27 41 451 2461
DURBAN OFFICE: +27 31 564 3200
EMAIL ADDRESS: firstname.lastname@example.org