Do you know how your stock preparation equipment and rolls are really doing? Valmet audits provide a quick, economical and effective way to check whether your assets are performing at their best and to take action to optimize them.
Leading global developer and supplier of process technologies, automation and services for the pulp, paper and energy industries, Valmet, conducts audits to check the working conditions of a customer’s assets.
The smaller the mill maintenance organizations are, the fewer eyes there are to detect emerging or hiding stock preparation equipment or roll failures. The consequences of such events can be costly. In the worst-case scenario, an unforeseen failure can lead to unplanned production losses.
To prevent such situations, Valmet offers one or two-day audits to identify immediate and long-term service needs. Our proactive problem-solving enables our customers to avoid unplanned shutdowns in their process. Identifying maintenance needs early also reduces the risk of accidents and creates a safer work environment. Based on an audit report by Valmet, our customers can plan the maintenance tasks for their shutdowns more accurately and make budgeting easier.
Valmet experts also inform the clients about the latest technological innovations and improvements. The experts also provide an upgrade proposal to the customers to improve their process performance.
Watch: Top Paper Companies 2023
Much Depends on Stock Preparation
As long as stock preparation equipment works as expected, little attention is paid to its condition and maintenance. Its sudden poor and unreliable performance, however, has a crucial impact on the later stages in a paper or board making process.
For example, an unplanned refiner shutdown and lack of spare parts can cause extended availability challenges and a high financial risk for the mill. Poor equipment condition often leads to stock quality variations, higher energy consumption and uneven wear of refiner segments or plates. These phenomena can deteriorate stock quality and increase maintenance costs. In a refiner audit, Valmet’s experts update the installed base information, record the current refiner process values, identify any service or improvement needs, and inform the clients about upgrade possibilities and energy savings.
Case Example: Poor Condition of Conical Refiner
A mill had a runnability issue with its low-consistency Valmet Conical RF-3 Refiner, mainly during refiner loading. Valmet carried out a mechanical audit, during which the refiner was opened, and its condition and damages were checked. It was discovered that the problems were mainly related to poor equipment maintenance. The damaged and rusty parts were replaced and reconditioned with special tools. Thanks to the audit and the actions taken based on the findings, the refiner runnability is now back at a high and stable level. Additionally, the mill has minimized the risk of unplanned shutdowns.
Optimal Roll Maintenance Adds to the Production Performance
Numerous roll-related challenges can lead to serious issues throughout the tissue, board or paper-making process. For example, rolls can cause long unplanned shutdowns and machine downtime when they need to be changed. Worn or outdated roll covers can also cause paper profile or runnability issues, as well as increasing energy usage through reduced dewatering.
A Valmet roll audit reveals issues like runnability problems and running time limitations related to rolls. Valmet’s experts identify roll-related production bottlenecks, benchmark roll maintenance intervals, record current roll process values and evaluate roll covers. They also check the mill’s spare roll situation and roll conditioning monitoring practices, evaluate roll grinding and storage facilities, and benchmark how the roll’s data is managed.
After the audit, Valmet provides its customers with an audit report that includes tips for improving roll performance, reliability and maintenance costs. By knowing the condition of the roll, the clients are able to reduce the risk of unplanned roll-related shutdowns or downtime thanks to optimized maintenance plans. They also get an idea of the technology level of rolls and are able to upgrade them & extend their run times based on the recommendations given.
Also Read: Paper Mart Emagazine Jun-July, 2024
Case Example: Press Suction Roll Cover Damage in Tissue Machine
A tissue producer had press suction roll cover issues and turned to Valmet for help. A roll audit revealed cover damage and low groove volumes, as the groove design was suboptimal. The roll cover showed edge damage due to a high temperature and nip pressure. The next time the rolls were ground, the groove design was changed according to an updated Valmet recommendation and the end area dimensions were improved (chamfer design). Performance was improved, with no additional costs to the customer, besides normal scheduled maintenance.
