Pump flow rate for 80w laser

[Peter Jones]

Does anyone know the flow rate requirements for 80w Reci lasers? It looks like many of the pumps used by the Chinese lasers have high flow rates. They look like they would flow 800-1100 gph, which seems like a lot of flow.

[Rich Harman]

Two to five liters per minute.

http://www.recilaser.com/2010/en_product/W2_en.html

[Peter Jones]

Thank you, Rich. I wonder why they are using such large pumps when a pump 1/10 the size would do.

[Rich Harman]

Who is "they"? Could it be that you are looking at the specs for the air assist pumps?

I am unable to find the flow rate specs for the CW5000 which is a good refrigerated chiller but the CW3000 specs a max flow rate of 15 l/min. I imagine the 5000 is about the same. That is only 3x what Reci calls for. A higher flow rate is harmless so long as it doesn't over pressure the system. Consider also that the fluid has to travel a long distance through narrow tubing, many fittings and a laser tube. The actual flow rate is going to be less than the max flow stated on the chiller.

[Peter Jones]

Just random Chinese vendors, they seem to ship aquarium pumps with the smaller machines and from the size of it, it looks like the larger pumps I use in my fish tank. The low flow rate on the chillers make sense--water contact with with cold coils need to be long enough to lower the temp.