Valves, like other mechanical products, also need maintenance. If this work is done well, it can extend the service life of the valve. The following will introduce the maintenance of the valve.
1. Valve storage and maintenance
The purpose of storage and maintenance is not to damage the valve in storage or reduce the quality. In fact, improper storage is one of the important reasons for valve damage.
Valve storage, should be in good order, small valves on the shelf, large valves can be neatly arranged on the warehouse ground, not disorderly pile, do not let the flange connection surface contact the ground. This is not only for aesthetic reasons, but mainly to protect the valve from breakage.
Due to improper storage and handling, hand wheel broken, valve stem crooked, hand wheel and valve stem fixed nut loose loss, etc., these unnecessary losses should be avoided.
For valves that are not used in the short term, asbestos fillers should be removed to avoid electrochemical corrosion and damage to the valve stem.
The valves that have just entered the warehouse should be inspected. For example, rainwater or dirt entering during transportation should be wiped clean and stored.
The inlet and outlet of the valve should be sealed with wax paper or plastic sheet to prevent dirt from entering.
The valve processing surface that can rust in the atmosphere should be coated with antirust oil to protect it.
The valves placed outdoor, must be covered with rainproof and dustproof items such as linoleum or tarpaulin. The warehouse where the valves are stored should be kept clean and dry.
2. Valve operation and maintenance
The purpose of operation and maintenance is to prolong the valve life and ensure reliable opening and closing.
Valve stem thread, often with the valve stem nut friction, to be coated with a little yellow dry oil, molybdenum disulfide or graphite powder, lubrication.
For the valve that is not often opened and closed, it is also necessary to regularly rotate the handwheel and add lubricant to the stem thread to prevent biting.
For outdoor valves, a protective sleeve should be added to the valve stem to prevent rain, snow and dust rust.
If the valve is mechanically standby, it is necessary to add lubricating oil to the gearbox on time.
Keep the valve clean frequently.
Regularly check and maintain the integrity of the other parts of the valve. If the fixed nut of the handwheel falls off, it must be matched, otherwise it will grind the four sides of the upper part of the valve stem, gradually lose the reliability of the matching, and even fail to start.
Do not rely on the valve to support other heavy objects, do not stand on the valve.
The valve stem, especially the thread part, should be wiped frequently, and the lubricant that has been soiled by dust should be replaced with a new one, because the dust contains hard debris, which is easy to wear the thread and the surface of the valve stem, affecting the service life.
3. Maintenance of valve packing
Packing is a key seal that directly relates to whether leakage occurs when the valve is opened and closed, if the failure of packing, resulting in leakage, the valve is equal to failure, especially the urea pipeline valve,because its temperature is relatively high, corrosion is relatively high, the packing is easy to aging. Strengthening maintenance can extend the life of packing.
When the valve leaves the factory, in order to ensure the elasticity of the packing, it is generally subject to static pressure test without leakage. After the valve is loaded into the pipeline, due to temperature and other factors, there may be seepage, then it is necessary to tighten the nut on both sides of the packing gland in time, as long as it is not leaked out, and then the seepage again, do not tighten once, so as to avoid the loss of elasticity of the packing and the loss of sealing performance.
Some valve packing is equipped with molybdenum disulfide lubrication paste, when used for a few months, should be timely to add the corresponding lubrication grease, when found that the filler needs to be added, should be timely increase the corresponding packing, in order to ensure its sealing performance.
4. Maintenance of valve transmission parts
Valve in the process of switching, the original lubricating oil will continue to lose, coupled with the role of temperature, corrosion and other factors, will also make the lubricating oil constantly in the dry. Therefore, the transmission parts of the valve should be regularly checked, found that the lack of oil should be filled in time, in order to prevent the lack of lubricant and increase wear, resulting in inflexible transmission and other failures.
Valve maintenance should be treated with a scientific attitude, in order to make the valve maintenance work to achieve the desired results and application purposes. In order to make the normal operation of production, reduce parking and increase economic benefits, in the valve, we must do these three points :
1.Correct selection of valves is the basis.
2.Proper use of the valve is the key.
3.Correct maintenance is the guarantee.
Post time: Mar-03-2023