DN700-DN3000 Full Face Rubber Expansion Joint

Key Design Features
Integral Full Face Sealing

The rubber bellows and flange faces form a seamless, integrated unit. Unlike conventional designs with separate gaskets, the full face rubber flange ensures the sealing surface covers the entire flange mating area. This provides superior leak-tight performance and compensates for minor flange surface irregularities or bolt hole misalignments.

Reinforced Construction

The expansion joint is manufactured using high-strength synthetic fabric reinforcement—similar to heavy-duty tire construction—combined with steel wire layers embedded within the elastomer body. This reinforcement provides excellent pressure-bearing capacity while maintaining the flexibility required for effective vibration and movement absorption.

Flange Options

The backing flanges are available in carbon steel (shot-blasted and painted or hot-dip galvanized) and stainless steel (304 or 316), drilled to accommodate ANSI, EN, DIN, JIS, or customer-specified standards. The full face design ensures bolts are installed within the flange edge, significantly increasing pressure resistance compared to standard rubber joints.

Performance Capabilities
Pressure and Temperature Ratings

For DN700 to DN2000 sizes, the expansion joints are engineered to handle operating pressures up to 16 bar (1.6 MPa), with test pressures up to 24 bar depending on design specifications. Temperature ranges vary based on elastomer selection:

When EPDM is selected, the joint operates within -20°C to +120°C, making it suitable for water, hot water, and weathering applications. NBR offers a range of -10°C to +100°C with good resistance to oils and hydrocarbons. Neoprene provides moderate oil and weathering resistance. Viton® extends the operating range to -10°C through +180°C, ideal for high-temperature and aggressive chemical environments.

Movement Absorption

The bellows design effectively absorbs axial movement (extension and compression to accommodate thermal expansion and contraction), lateral movement (off-set compensation for pipe misalignment), and angular deflection (accommodation of flange face angular variations).

Applications
Full Face Rubber Expansion Joints in the DN700–DN2000 range are ideal for water and wastewater treatment plants handling sewage, raw water, and treated effluent; large-scale commercial and industrial HVAC systems; pump and valve connections to reduce stress on equipment and absorb vibration; industrial piping systems in chemical processing, power generation, and mining; as well as marine applications including shipboard piping systems.

Advantages
No Gasket Required

The full face rubber flange eliminates the need for separate flange gaskets, simplifying installation and reducing maintenance costs while ensuring reliable sealing.

Superior Pressure Resistance

Because the flange and sphere end face are in complete contact, the product can withstand higher pressures—typically up to 2.5 MPa for full face designs compared to lower ratings for standard rubber joints.

Vibration Damping and Noise Reduction

The elastomeric construction effectively isolates mechanical vibrations generated by pumps and compressors, protecting sensitive equipment and reducing noise transmission through piping systems.

Cost-Effective Solution

Full face rubber expansion joints are lightweight, easy to install, and require minimal maintenance compared to mechanical expansion devices. They occupy less space and reduce installation labor costs.

Material Options
A variety of elastomer compounds are available to suit different service conditions. EPDM offers excellent resistance to weathering, ozone, and hot water, making it the preferred choice for water and wastewater applications as well as outdoor installations. NBR provides good resistance to oils and fuels, suitable for petroleum and hydrocarbon services. Neoprene delivers moderate oil and weathering resistance for general industrial use. Viton® is recommended for high-temperature and aggressive chemical media due to its superior thermal and chemical resistance. Hypalon offers excellent resistance to chemicals and ozone exposure, ideal for harsh chemical processing environments.