Principal Features of Meldin® 7000
Geometric Stability at High Temperature
Meldin® 7000 series materials exhibit extremely high geometric stability at elevated temperatures. Testing has shown Meldin® 7000 to have less than 0.04% variation from its original dimensions after cycling from 73°F (22.7°C) to 500°F (260°C) over a 2-day period.
Total Process Control…Powder-to-Parts
Our expanding resin production facility and our R&D testing labs allow Saint-Gobain Performance Plastics to maintain control of the quality and source of the base polyimide resin. Our “Powder-to-Parts” capability means total process control of resin production, stock shape manufacturing, direct forming, and critical dimensional machining of your finished parts.
Longer Life at Higher Loads and Speeds
The self-lubricating grades of Meldin® 7000 do not melt when exposed to high load (P), or high speed (V) applications, as compared to more traditional PTFE or thermoplastic polymers. P x V limits for Meldin® 7000 self-lubricating grades exceed 300,000 in dry environments and past 1,000,000 in liquid or grease lubricated environments.
Total Process Control…Powder-to-Parts
Meldin 7000 provides OEMs with direct access to Saint-Gobain’s design and co-engineering capabilities, material testing resources, and machining expertise, providing total process control from powder-to-parts.
Service offerings include machine shop capabilities, helping OEMs remove one level of the supply chain and streamline product development. Meldin 7000 also provides design and co-engineering expertise, such as engineer-to-engineer collaboration on technical issues, product development and prototype test parts. Finally, Meldin 7000 can validate and/or screen parts through rotating sealing ring and thrust washer testing.
Meldin® 7000 Series Compounds
Meldin® 7001
A thermosetting polyimide, Meldin 7001 is our unfilled base resin. This grade offers the maximum mechanical properties and high chemical resistance. The Meldin 7000 grade is ideal for electrical and thermal insulating applications. More ductile than ceramics, and lighter weight than metals, Meldin 7001 is a popular choice for structural parts in aerospace and other applications where metal replacement is desirable.
Meldin® 7221
Meldin 7211 has 10% PTFE and 15% graphite filler, which provides our lowest coefficient of friction grade.
Meldin® 7003
Meldin 7003 includes 15% molybdenum disulfide lubricating filler for wear applications that operate in a vacuum or in very dry conditions.
Meldin® 7021
Meldin 7021 is our self-lubricating grade. Meldin 7021 has 15% by weight graphite fillers, encapsulated by the base polyimide resin. With its low coefficient of friction and high heat resistance (up to 900°F [482°C]), Meldin 7021 provides our customers the best all-around choice for high temperature bearings, seals, and other low-wear applications.
Meldin® 7022
With 40% graphite filler, the Meldin 7022 grade offers additional dimensional stability and the lowest coefficient of thermal expansion of any Meldin grade.
Meldin® 7000 Material Uses and Applications
Aerospace
Able to withstand continuous use up to 315° C (600° F) and intermittent use up to 482° C (900°F), and chemically resistant to solvents and other serospace chemicals, Meldin 7000 is ideal for challenging aerospace applications. With its exceptional wear resistance, superior electric and thermal insulation properties, and low coefficient of friction, Meldin 7000 can be used in components such as bushings, bearings, thrust washers, and celing rings commonly found in auxiliary power units (APUs), de-icing systems, cabin air-conditioning systems, actuators, jet engines, and landing gear systems.
Specialty Glass Containers
For the manufacturer of specialty glass containers, the process required a low friction, high temperature resistant surface that would not cause cracking or visual damage while the containers slide across the surface. A unique hole pattern was developed to provide a controlled cooling operation for the containers. Meldin® 7022 was chosen due to its high geometric stability and ability to provide a smooth sliding surface without causing any damage to the glass.
Hydraulic and Hot Gas Piston Ring
Meldin® 7211 is used in critical hydraulic and hot gas piston ring applications because of its high temperature resistance and low friction, particularly against soft metals like aluminum and stainless steel. In addition, the custom piston ring overlap design minimized leakage and improved overall efficiency of this self-lubricating ring seal.
Thermal Insulator in a Hot Runner Nozzle
Meldin® 7001 unfilled polyimide grade was used as a thermal insulator in a hot runner nozzle for an injection molding machine. Designed especially for molding the highest temperature materials, the hot runner nozzle required a tip that thermally insulated the molten plastic from the nozzle housing while preventing a color transfer of the molten plastic onto the nozzle tip. This allowed the user to quickly change the resin colors without having to disassemble and change the nozzle.
