Figure 1. Rotary Union for Advanced High-Speed Liquid-Cooled Generators and Motors and
Through-the-Tool Coolant Systems for Machining Centers
The Navy needs robust high-speed rotary unions for advanced high-speed liquid-cooled generators and motors. Under a Phase II SBIR contract for the Naval Sea Systems Command (NAVSEA), we developed a Rotary Union to meet Navy needs. Our Rotary Union can also be used to admit coolant into a rotating spindle for through-the-tool coolant systems for Machining Centers. Our Rotary Union uses hydrostatic radial and thrust bearings to support a rotor and maintain tight clearances in clearance seals. Figure 1 shows our Rotary Union in a setup for testing. Our setup includes a servomotor, which is driven by a computer-controlled servomotor drive to achieve desired rotational speeds for our Rotary Union. We demonstrated the capability of our Rotary Union to pass 5 GPM of coolant with only a 43 psi pressure drop at a rotational speed of 12,000 RPM. Hydrostatic bearings can operate at large radii with fast rotational speeds, so our Rotary Union has room for large flow capabilities. The hydrostatic bearings offer the same advantages to our Rotary Union that hydrostatic bearings offer to spindles of high-precision high-speed machine tools (including nano-precision diamond-turning lathes for optics): high-speed capability, long life, durable, reliable, large damping of shocks and vibrations, and dynamically stable. Proprietary designs give our Rotary Union for liquid-cooled generators minimal seal leakage. Our Rotary Union uses materials that give our Rotary Union graceful degradation to avoid catastrophic failures.
Through-the-Tool Coolant Systems for Machining Centers
The Navy needs robust high-speed rotary unions for advanced high-speed liquid-cooled generators and motors. Under a Phase II SBIR contract for the Naval Sea Systems Command (NAVSEA), we developed a Rotary Union to meet Navy needs. Our Rotary Union can also be used to admit coolant into a rotating spindle for through-the-tool coolant systems for Machining Centers. Our Rotary Union uses hydrostatic radial and thrust bearings to support a rotor and maintain tight clearances in clearance seals. Figure 1 shows our Rotary Union in a setup for testing. Our setup includes a servomotor, which is driven by a computer-controlled servomotor drive to achieve desired rotational speeds for our Rotary Union. We demonstrated the capability of our Rotary Union to pass 5 GPM of coolant with only a 43 psi pressure drop at a rotational speed of 12,000 RPM. Hydrostatic bearings can operate at large radii with fast rotational speeds, so our Rotary Union has room for large flow capabilities. The hydrostatic bearings offer the same advantages to our Rotary Union that hydrostatic bearings offer to spindles of high-precision high-speed machine tools (including nano-precision diamond-turning lathes for optics): high-speed capability, long life, durable, reliable, large damping of shocks and vibrations, and dynamically stable. Proprietary designs give our Rotary Union for liquid-cooled generators minimal seal leakage. Our Rotary Union uses materials that give our Rotary Union graceful degradation to avoid catastrophic failures.