Anti-rust issues of bolts
Thread Content
What anti-rust measures should be taken for the bolts used to connect the flange of the steam tracer and its return water station? The temperature is about 220 degrees Celsius, and it is put into use from October to April next year! From daily observation, the bolts are extremely rusty!
Generally speaking, these are our daily practices for anti-corrosion of fasteners. However, if the exposed parts of the bolts of key equipment are long and placed in the open air, it is generally best to add a protective cover.； Another is that fasteners that need protection and maintenance must be oiled regularly. At the same time, material fasteners of corresponding media must be selected.
Try applying butter or applying high-temperature paint.
It's 220 degrees, and oiling doesn't seem to work very well.
There's nothing wrong with it, just overhaul and replace it all.
Apply some high-temperature paint first, then apply butter after installation.
First paint some high temperature resistant paint, then apply a layer of butter, and coat the thicker steel pipe
The poster only saw the anti-corrosion of the flange bolts. After several years of use of the steam heating cable (which was insulated with the process pipelines), the corrosion became severe. One of the key tasks of the installation every year (in the area north of the Yellow River) is to plug the heat tracing leaks and deal with the east blockage of the heating cable.
If the inspection is in place in time, the steam heating cable will not be cracked by freezing!
You can use imported galvanized anti-corrosion bolts and nuts, or you can use ordinary domestic bolts and nuts and paint them with high-temperature anti-corrosion paint, then make a flange sealing cover and pour butter into it (the butter must be checked and replaced regularly). The anti-corrosion effect is also good!
There seems to be no better way. In actual operation, butter is mostly used.
Just smear some butter on it and it will be a perfect solution.
Galvanized bolts and nuts should be fine
The simplest and most practical thing is to apply butter.
1. Lithium molybdenum disulfide grease, 2. Anti-seize agent.
The steam temperature is 220 degrees, and the pressure is not very high. The rust of the bolts used at a pressure of more than ten kilograms is nothing to worry about. It is just a little rusty on the surface. When it is actually disassembled, it can be easily disassembled by spraying some rust loosening agent. Anti-rust without increasing the cost is not very effective.
Generally, butter is applied. Although the temperature is high, the exposed part of the bolt is slightly lower. Do not use anti-rust paint, high-temperature paint and other paints to coat the threads of the bolts. The stickiness will be very strong and it will be difficult for the nut to come out of the threads during the next maintenance. In addition, in recent years, we have gradually begun to use a large number of stainless steel bolts and nuts to replace carbon steel. Although the one-time cost is more, the service life is long, the maintenance workload is small, and the maintenance speed can be accelerated.