AR®HT Composite Bushings

Challenge
Our customer, a global paper products and packaging company, utilizes Viking LL 125 pumps to apply the latex coating required to protect and color its packaging products. These pumps offer the customer a robust pumping solution with infrequent failure – with one specific exception. The pumps’ bushings, manufactured from inherently brittle and easily broken carbon material, caused frequent operational interruptions. When the carbon bushings failed and required replacement, the fragile components often broke during installation. During routine maintenance, if a pump’s bushings were removed for other repair requirements, they often crumbled during removal and had to be replaced. In addition, vibrations caused by premature bushing failures contributed to mechanical seal failures, leading to dangerous product leakage. These multiple component issues led to added pump downtime, as well as increased maintenance and inventory costs.

Solution
To solve this customer’s challenges, Greene, Tweed utilized its proprietary ARHT thermoplastic material developed specifically for bushings, bearings and wear rings for pumps handling abrasive media. The ARHT bushings provide outstanding chemical, thermal shock and impact resistance, making it an ideal replacement for the brittle carbon bushings. The solution combines excellent abrasive resistance, good dry run capability and superior vibration dampening characteristics with no hydrolysis or swell.

Results
By installing Greene, Tweed’s ARHT bushings in its Viking pumps, the customer has achieved simplified bushing installation and significantly increased reliability, boosting the MTBF from 2 months to over 15 months. Because the new bushings handle abrasive materials and vibration better than the legacy carbon material, the customer has reduced maintenance costs through lower instances of seal failure. In addition, the customer is now able to reuse the ARHT bushings if they are removed for other maintenance needs, realizing a lower total cost of ownership.