Case Study

The Problem

A high profile news ink manufacturer required support after several premature failures of a Burgmann MR1SF5-125 mechanical seal cartridge fitted to a large Netzsch LMZ1 production mill.

The mill was installed to increase throughput and reliability, but poor seal performance was adversely affecting production.

The Solution

A mechanical seal unit was sent to NASH for evaluation.

The primary dynamic inboard o-ring was extruded and cut through. There was also evidence of thermal and mechanical damage to the o-ring material (viton rubber). The seal was contaminated with ink and the inboard seal faces were chipped and scored.

An investigation into the service history of the mill confirmed that water cooling to the main barrel was manually isolated when the mill was stationary to

prevent the media and beads cooling and solidifying. However, there was the possibility that occasionally, cooling was not re-started with the mill, causing rapid heat build up that exceeded the maximum temperature rating of the inboard dynamic o-ring.

The company was advised to automate barrel cooling to prevent a recurrence of this failure mode. The seal was repaired, tested and returned to site.

Please see Inspection Report for more information.

The Benefits

By providing specialist aftermarket support for this type of seal, NASH had the necessary technical knowledge and resources to identify the root cause of the problem and advise a solution.

The user is now enjoying the full benefit of their investment.