Flatbox vacuum varying
Note: When measured, flatbox vacuum is often different on the two sides of the machine. 1. Ensure the following: (a) that flatbox heads are correctly set. (b) that boxes are not filling at forming fabric changes. (c) that applied vacuum is not varying due to malfunction at pumps or in supply piping. (d) that level […]
Couch vacuum varying
1. First, it must be determined whether the source vacuum or sheet resistance is changing. 2. Check vacuum pumps and seal water, and check for slipping belts. 3. Check that consistency of mixed stock is steady. 4. Examine the basis weight profile. — is it steady with time? 5. Check total head in headbox for […]