Maintenance issues with Hydropurge Isolation


Pulp and Paper

Business Issue

The hydro-purge isolation valve was causing four to six work orders per year requiring full replacement of the valve.  Process availability was affected each time the valve needed replacement.  The mill’s maintenance budget was negatively affected due to the costs of the replacement valves and labor to install the valves.

Project Summary

Cornerstone Controls was challenged with providing a solution that would do two things:

  • Eliminate the process issues
  • Reduce the plant maintenance planner’s expected yearly spend for the application. 

Cornerstone worked closely with knife-gate manufacturers’ engineering staff to research other similar applications and determine what specific issues were unique to the customer.

After the final design was agreed upon, a Cornerstone Controls representative outlined how this solution was different, and the details around why the proposed solution would correct the customer’s problems.

Scope Responsibility

Cornerstone Controls was responsible for the following areas:

  • Identify the conditions causing the failure with the present knife-gate valve
  • Design a solution that did not require piping modifications
  • Track performance and maintenance over the new solutions lifecycle


A new, properly applied knife-gate valve solution was engineered by Cornerstone Controls and installed at a cost less than the original valve. The new valve's lifecycle has proven to be eight times longer than the previous valve and is now the standard for the application.