Rubber diaphragm technology and design

Materials and Formulation Design

The formulation design of the rubber compound for rubber diaphragms is a crucial technical step, requiring comprehensive consideration of performance requirements such as resistance to various media and aging. For example, for specific media like crude oil, the formulation must possess corresponding resistance properties. Specific formulations may use a combination of multiple rubbers, such as natural rubber and EPDM rubber (in a ratio of 5-20 parts natural rubber to 80-95 parts EPDM rubber), along with homogenizers, activators, antioxidants, plasticizers, fillers, reinforcing agents, vulcanizing agents, and accelerators, to achieve comprehensive properties such as low compression set, high strength, and ozone aging resistance at low hardness.

 

Structure and Type Design

Main structural types include pure rubber diaphragms, fabric-reinforced diaphragms (with strong fabrics such as nylon, polyester, or aramid sandwiched in the middle or on one side), metal composite diaphragms, as well as flat diaphragms, corrugated diaphragms, disc diaphragms, and rolling diaphragms. To improve performance, innovative structural designs can be employed. For example, corrugated grooves on the outer and inner rubber layers reduce wrinkling during deformation, enhancing diaphragm toughness. Multi-layered composite structures, such as metal-rubber-plastic ternary composites, balance material strength and elasticity to adapt to high-frequency operating scenarios.

 

Specialty Material Applications

To meet harsh operating conditions such as high speed, high pressure, corrosion resistance, and resistance to high and low temperatures, rubber diaphragms often utilize specialty rubber materials or undergo material modification. Commonly used materials include nitrile rubber (NBR), hydrogenated nitrile rubber (HNBR), ethylene propylene diene monomer (EPDM), fluororubber (FKM/FPM), and silicone rubber (Silicone/FVMQ). Furthermore, research is focused on developing new materials, such as ECO materials, and applying corrosion-resistant coatings, stainless steel reinforcement layers, or nanoscale coating technologies to improve the diaphragm's service life and environmental adaptability in specific media (such as mineral oil, acids, and alkalis) or high-temperature environments.