Fault characteristics of paper machine

When the paper machine equipment or system is in use, when the specified function is lost or the performance is reduced due to some reason, it is called equipment failure. There are two main types of downtime failures of paper machines: inherent production failures and equipment failures.

(1) The characteristics and rules of paper machine's inherent production failure and shutdown

This type of shutdown is mainly to ensure the quality of the product and meet the requirements of the production process, especially the production of high-end cultural paper is more prominent, the main reasons for the shutdown: First, the scrubbing work, the wet end filtration and dehydration components (or materials) After using it for a certain period of time, its function decreases, and the initial effect of water removal and filtration cannot be achieved, and it needs to be cleaned regularly. The second is to replace the main process equipment. For example, the copper mesh and felts need to be replaced regularly after their service life is reached; the press rubber rollers and stone rollers are contacted and worn by the paper and scraper, and the middle height of the roller surface changes, which will affect the product quality and need to be repaired regularly.

(2) The characteristics and analysis of equipment failure shutdown of paper machine

Due to the particularity and complexity of the paper machine production process, equipment failure has the following characteristics:

1. There are many equipment failure points, and equipment failure and shutdown often occur;

2. The service life of some parts is short, and the frequency of replacement of spare parts is high;

3. There is a large gap between the failure cycle and the occupied maintenance time, which is difficult to manage. There are many reasons for the equipment failure of the paper machine. The main causes of equipment failure are:

1. Wear and tear: Reason one, long-term wear parts and equipment in contact with copper mesh, wool cloth or pulp, forming paper, such as pulp pump, pulper, desander, vacuum box panel, press roll, calender roll, etc.; The second reason is the relatively frequent movement of parts, such as scrapers, steam inlets, cylinders, vacuum rolls, vacuum pumps, etc.

2. Lubrication: Mechanical rotation is inseparable from bearings. Paper machines with rotating rolls are the main type. There are many types and numbers of rolls. There are hundreds of bearings of various types. Therefore, lubrication management is very important, especially when it is exposed to water, high temperature, Under the influence of heavy load, lubricating oil (grease) is easy to lose, evaporate, and age, which will damage the lubrication effect and cause bearing damage and shaft head wear. Therefore, regular inspection and refueling is essential.

3. Fatigue: Heavy-duty and continuous-running machinery are prone to fatigue damage. On the paper machine, because some parts are restricted by the mechanical structure and operating principle, the design strength of the parts (such as the screen shaking spring plate, electromagnetic clutch sucker, coupling anti-overload pin, etc.) should not be too large to avoid damage. As a solution, measures such as maintenance and technical transformation can be taken.