WR® 650 – Superior dry run capability and near universal chemical resistance up to 500°F

by:Greene Tweed

When fluids stop moving through pumps, an upset condition called dry run occurs, resulting in higher operating temperatures and increased wear and vibration. This could happen during startup, when a pump’s bearings and wear rings may have insufficient process media for lubrication. The result is a dry running scenario during which the mating surfaces will wear. A short-term dry run condition may not be a problem, but a dry run of a longer duration could lead to complete pump failure.

Regardless of the time frame under which dry run occurs, this upset condition can result in costly repairs and a reduced MTBR/MTBF (mean time between repair/mean time between failure). One solution would be to use a material that offers superior wear and dry-run capabilities, increases MTBR/MTBF, and improves rotating equipment reliability and efficiency, thereby resulting in cost savings.

Greene Tweed’s WR® 650 PFA composite is that solution. Its unique, 3D braided, carbon fiber structure wrapped in a PFA matrix offers superior wear and dry-run capabilities that are particularly beneficial for stationary wear parts in centrifugal pumps (e.g., vertical, horizontal, single, and multi-stage pumps) used in refinery, chemical, water treatment, and power plants.

WR® 650’s differentiator is its unique, 3D braided, carbon fiber structure wrapped in a PFA matrix that provides great non-gall and non-seize properties. Acting as a sacrificial component, the self-lubricating nature of PFA ensures metallic counter parts are preserved, even those that are relatively soft.

WR® 650 also exhibits radial CTE (coefficient of thermal expansion) comparable to steel, and operability from cryogenic to 500°F (260°C) applications. Tribological test results (plain bearing on shaft method) conclude the PV limit for WR® 650 exceeds other competitive PFA-based materials by 2.5 times before exhibiting signs of degradation.

WR® 650 is also an excellent material choice for chemically harsh environments. It’s almost universally chemically resistant to withstand applications where PEEK-based products are insufficient.

WR® 650 is available as custom machined-finished parts as requested, stock shapes from 2- to 12-inch OD, and a standard 6-inch length (larger sizes are possible).

Greene Tweed also offers the broadest range of high-performance thermoplastic composite materials (ideal for wear rings, bearings, bushings, etc.) including WR® 300, WR® 525, WR® 575 and WR® 600 for normal- to-high wear-resistant applications, and AR®-1 and AR®-HT for abrasion-resistant applications.

Greene Tweed products are sold and distributed worldwide. Click here (https://www.gtweed.com/contact-us/) to contact Greene Tweed regarding our composite material solutions.