Maintenance of flat gate valve during operation

Maintenance of flat gate valve during operation

The purpose of maintenance during operation of the flat gate valve is to ensure that the valve is in a clean, well-lubricated, complete, and normal operating state all year round.

1. Exclusions for flat gate valves:

The appearance of the valve, the trapezoidal thread on the valve stem and stem nut, the sliding part of the stem nut and bracket, as well as gears, worm gears and other components are prone to dust, oil, media residues and other dirt.

Wear and corrosion will occur on flat gate valves. Therefore, it is obviously very important to keep the inside and moving parts of the valve clean and to protect the integrity of the flat gate valve paint. The dust on the flat gate valve is suitable for brush sweeping and compressed air blowing; the dirt on the trapezoidal thread and between the teeth is suitable for rag scrubbing; the oil stains and media residues on the valve are suitable for steam blowing, or even scrubbing with a copper wire brush , until the processed surface and matching surface show metallic luster, and the painted surface shows the essence of paint.

The trap should be inspected at least once per shift by a dedicated person, and the flush valve and the plug at the bottom of the trap should be opened regularly for flushing, or disassembled and flushed regularly to prevent dirt from clogging the valve.

2. Lubrication of flat gate valves.

The trapezoidal thread of the valve, the sliding parts of the valve stem nut and the bracket, the bearing parts, the meshing parts of the gears and worm gears, the worms, and other joint moving parts all require good lubrication conditions to reduce mutual friction and avoid Wear each other. Some parts are specially equipped with oil cups or nozzles.

If they are damaged or lost during operation, they should be repaired and equipped, and the oil lines should be clear. Lubricated parts should be refueled regularly according to specific conditions. Valves that are often opened and have high temperatures are suitable for refueling once a week to a month; valves that are not frequently opened and have low temperatures can have a longer refueling cycle. Lubricants include organic oil, butter, molybdenum disulfide, graphite, etc.

High-temperature valves are not suitable for use with engine oil and butter, which will be lost due to melting at high temperatures. They are suitable for injecting molybdenum disulfide and graphite powder into exposed parts that need lubrication.

For example, if grease and other greases such as butter are used in trapezoidal threads and gears, they will be easily contaminated by dust. However, if molybdenum disulfide and graphite powder are used for lubrication, they will not be easily contaminated by dust, and the lubrication effect is better than butter. Graphite powder is not easy to apply directly. It can be mixed with a little oil or water to form a paste. Oil-sealed plug valves should be filled with oil according to the specified time, otherwise they are prone to wear and leakage.

3. Maintenance of flat gate valves.

All valve parts should be complete and complete during operation. The bolts on the flange and bracket are indispensable, and the threads should be intact and no loosening is allowed. If the fastening nut on the handwheel is found to be loose, tighten it in time to avoid wearing the connection or losing the handwheel and nameplate.

If the handwheel is lost, it is not allowed to replace it with an adjustable wrench and must be replaced in time. The packing gland is not allowed to be skewed or have no preload gap. For valves in environments that are easily contaminated by rain, snow, dust, sand and other contaminants, a protective cover should be installed on the valve stem.

The scale on the valve should be kept complete, accurate and clear. The valve seals, caps, pneumatic accessories, etc. should be fully prepared. The insulation jacket should have no dents or cracks. It is not allowed to knock, stand on or support heavy objects on the running valves; this is especially prohibited for black and white metal valves and cast iron valves.