Vespel® SCP-5050 Saves Weight and Extends Shroud Life

Jet engine shrouds made with high-temperature resistant Vespel^® SCP-5050 composite material offer proven impact resistance and potentially significant weight savings (40% less versus aluminum; 75% less versus stainless steel and titanium). Shrouds made with Vespel^® SCP-5050 also provide longer component life thanks to reduced wear interfaces, utilization of bearing material for the entire shroud, and elimination of bushing life issues.

Composite shrouds provide a low-friction, wear-resistant surface that prevents damage to expensive metal vane stems. Further, Vespel^® SCP-5050 can simplify design and assembly, and the weight savings realized by using this material can help improve aircraft fuel efficiency, range and payload capacity. 

Application

• A shroud is a segmented ring with holes drilled radially outward for variable vane stems used inside a jet engine compressor. Some are split.
• Grooves are cut into shroud to accept metal connecting ring, frequently with an abradable seal.
• Shrouds are typically aluminum, stainless steel, or titanium.
• Shrouds utilize bushings to enhance wear and reduce friction for variable vane stems.
• Inner shrouds typically float on the engine axis.

Challenges

• Damage can occur to expensive metal components such as vanes if bushings wear out prematurely.
• Components need to withstand thermal excursions for duration of expected engine life.
• Shrouds need to withstand impact, loading, and maintain relative location of vanes.
• Shrouds need to be designed to allow simultaneous assembly with multiple vanes.

More Hot Wear Resistance

Solution

Design shrouds in light weight, high temperature, wear resistant Vespel^® SCP-5050 composite material instead of metal.

Features and Benefits

• High temperature material capabilities in application environments in excess of 600^°F/315^°C.*
• Longer component life due to reduced wear interfaces, utilization of bearing material for entire shroud, and elimination of bushing life issues.
• Proven impact resistance.
• Potential weight savings of 40% over aluminum and 75% over stainless steel and titanium due to lower density of composite materials.
• Fewer parts to stock and assemble through bushing elimination.
• Lower system cost through part consolidation.
• Provide largest subassembly possible.
• Lower friction vs. metal with dynamic coefficient of .2 or less.
• Vibration dampening properties of composites versus metals.

Stiff when Hot