Questions about low-temperature vertical bag pumps
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I’m seeking advice from fellow sailors: my installation requires a methane pump, with an operating temperature of -145°C. Some suggest using a low-temperature vertical cartridge pump. I have no experience operating pumps at such low temperatures, and the information available online isn’t very clear either. Is the operation and maintenance of this type of pump complicated? What is its operational stability like? Which manufacturers’ equipment is generally used? It would be ideal if it’s something that Haiyou has used themselves. Thank you!
There are domestic ones as well as imported ones. The operation is not complicated, and it runs fine. Domestically produced, equipped with Japanese machine seals. :P:P
Use a barrel pump? If money isn’t a concern, go with Sulzer. But it’s really hard to say whether this temperature is appropriate when using this cartridge pump. The mechanical seal of the barrel pump is exposed, so frosting must be severe. Moreover, the couplings are rigid, and both the shaft and the motor are at extremely low temperatures. -Methane at 145°C is essentially pressurized LNG; I think low-temperature submersible pumps are more reliable.
We also considered using a submersible pump, but our tank is relatively small with a low flow rate, so it’s not possible to install one inside the tank
API 610 VS6 pumps typically use double-end mechanical seals, along with plan62 nitrogen purging to prevent freezing at the seal area. Flexible coupling – this pump is very useful. Just consider the maintenance space. If only the mechanical seal needs to be replaced, there is no need to take the pump out.
We have used vertical cartridge pumps from Sulzer; the operating temperature isn’t that low, and the performance is fairly stable. Replacing the seal bearings is relatively easy. However, disassembling the pump for maintenance is quite troublesome and requires a crane. The materials used must be clean, otherwise jamming can easily occur. If you are dealing with a medium at low temperatures, then you should use the Plan62 model mentioned above, which comes with a nitrogen seal – but it’s important to control the amount of nitrogen used, otherwise it could have the opposite effect
These days I’ve seen vertical barrel bag pumps; in the 53B model, there is a pipeline on the outside for injecting nitrogen, and there’s no discharge pipe or anything similar. It doesn’t seem to be a dry gas seal, and I’m not sure why. I’m really clear now after seeing my buddy’s answer; thanks!