Case Studies

The Problem

A coatings manufacturer experienced a seal failure on a Netzsch LME mill.

The seal, a Merkel double seal unit, size 95 mm, had run successfully for nearly 3 years since the last repair by NASH.

The Solution

NASH sent a service exchange mechanical unit to site on a guaranteed next day early morning delivery.

The replacement seal was fitted immediately and the mill was back in service within 24 hrs. The failed seal was returned to NASH for assessment and repair. Key observations included

• Heavy internal product contamination
• Badly worn seal faces
• Heat damaged o rings

Further investigations with site operators confirmed there had been a production problem that caused mill pressure to exceed seal system pressure and this had allowed product to enter the seal.

The seal failed soon after this upset due to heavy product contamination, with all sealant leaking to atmosphere.

However, because of short term production demands, the decision was taken to continue running the mill by isolating the seal system pressure switch and allowing the seal to run dry. This explained the heavily worn faces and heat damaged O rings.

 

The Benefits

By working with NASH and the equipment manufacturer, the company was able to take advantage of a service exchange programme that ensured their mill was up and running again within 24 hrs.