Jun 29, 2021
Forming section services provide important information about the potential or actual problems that may occur and their solutions. In addition, regular scheduled services ensure the reliable, safe and efficient operation of the forming section.
It has been shown that more than 50 percent of vacuum systems suffer from poor efficiency. In most cases, relatively simple improvements and inexpensive installations can significantly reduce energy consumption. Valmet's vacuum system study is a simple and efficient method for identifying potential improvements.
A machine's vacuum system accounts for 10–20 percent of its electricity consumption, which means 40–100 kWh/tpaper. By identifying and tapping into potential savings, the energy consumption of a vacuum system can be reduced by up to 30 percent. The graphic shows the electricity consumption of a newsprint machine vacuum system.
The study targets improvements in the energy efficiency and controllability of the vacuum system, and determines the feasibility of existing vacuum system modification. The study also provides you with capacity requirements for the main equipment, necessary new controls and an improved estimate of the energy savings potential.
An energy analysis starts with a desktop study and benchmarking that utilizes PI diagrams and information on the vacuum system's operating conditions. If this evaluation reveals any potential for energy savings, a more detailed vacuum system study with field measurements is recommended to identify specific necessary actions.
The vacuum system study includes:
Based on all the information gained, Valmet draws up a report including vacuum system capacity calculations and concept evaluations. The report provides you with recommendations presented in the existing PI diagrams, and investment cost estimates and payback times.
Maintaining good forming section frame condition is important to provide for safe, reliable and high-quality operation of the paper machine. A key input for good maintenance is a thorough mechanical audit, which provides the condition of all the key components of the forming section.
Reasons to conduct a mechanical audit on the forming section include:
The audit includes a visual analysis consisting of:
If the wire has been removed during the shutdown, additionally:
The breast roll shaker plays an important role in the quality and strength of paper and board. Valmet's shaker services – inspection and service – determine the current condition of the unit and ensure its reliable operation through good servicing.
The breast roll shaker improves the quality and strength of low-quality pulp paper/board. It is therefore vital to keep the breast roll shaker in good condition to ensure the best possible operating profit. Valmet Breast Roll Shaker services include a thorough inspection of all related components with measurements, tests and visual inspections.
Shaker service actions performed at the mill site typically include:
All worn wear parts are replaced during the service, while possible damaged parts are changed and recorded for further investigation. Works conducted and all findings from the unit are presented after the service on site, and a more detailed report is provided after the visit.
Inspection actions done at the mill site typically include:
Valmet's breast roll shaker inspection includes a thorough check of all related components with measurements, tests and visual inspections. All findings from the inspection are presented after the service on site, and a more detailed report with an analysis of the unit is provided after the visit.
It is recommended that the breast roll shaker service and inspection are performed alternately, with one happening each year. Service takes 2-3 days and inspection 1 day.
For more information about maintaining your forming section in peak operating condition, contact your Valmet representative.