Have you used flat gate valves?
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Have you ever used a flat gate valve? The valve disc is a flat plate; generally, there are two such discs, with a spring between them. The elastic force of the spring, along with the pressure in the pipeline, presses the outer valve disc against the seal. The valve disc has shear strength – it can cut through 6mm thick rebar during tests. It is said to be suitable for use in catalytic slurry systems and catalyst systems. We installed one of these valves at the inlet of the slurry pump. Now that the unit is in operation, inspections have revealed severe internal leakage in this valve, and it is no longer possible to repair the pump. It’s really troublesome. I wonder if any of you who use such products have encountered this issue? Help me think of other ways I can remove the pump for repair
Parking for repairs! There is no other way. Poster: Are you choosing a pump for cutting rebar? Does it still serve a regulating and shutting off function?
I came across flat gate valves in a previous project; they seem to be used with fluids that have high viscosity. I’m not sure where your valve is installed; take a look at the flow diagram. If it’s part of a certain process unit, then shut down that unit, use another parallel unit to operate temporarily, and then remove and replace the valve. Ask the senior mage on site.
If there are no other valves that can be shut off before or after it, it seems the poster will have to stop the machine for maintenance! !
There’s usually a backup pump, right? Switch to the backup pump and then replace the current valve
When the pressure in the pipeline is not high enough, flat gate valves do not seal properly; in such cases, wedge gate valves are generally used. However, usually a check valve is installed between the pump and the valve, in order to prevent problems that may occur if there is leakage within the gate valve
Hehe, this kind of behavior is common in many petrochemical companies. Since the catalytic slurry contains catalyst powder, the sealing surfaces of the gate valves you use are not wear-resistant, resulting in easy internal leakage. It is recommended to consider ceramic gate valves. As for how to repair the pump, some companies find ways to cool the slurry in the pipes until it becomes something similar to a solid state, before switching the pipes.
For use in media with high viscosity and solid particles, valves equipped with surface coatings (such as nickel-based alloys, chromium carbide, tungsten carbide, and other hard alloys) should be selected; it is also advisable to have a purging function, as this will extend the valve’s service life；
It sounds like a parallel double-plate gate valve, which is generally used with gaseous media; when closed, the two plates press against the sealing rings on both sides of the valve body. It generally doesn’t have a shearing function; those with a shearing function are circuit breakers. Maybe I’m out of date
Reply to 9# roeao123: Yes, the sealing surface treatment for flat gate valves is very important. A high-hardness and smooth anti-corrosion coating should be used.