Suction!

[suckolux]

Ok guys, twirl this one around, I know there is a correct answer, going to guess Dave has it for sure. On suction, is there a measure for the strength of the pull and one for the volume of it? Like water or electricity flow? Just finally had to ask. Hope this gets the marbles rolling.

 

[elux89]

Suction = Inches of Water Lift

Suction is usually measured in inches of water lift. Sometimes the rating will be given in inches/millimeters of mercury as well.

 

[suckolux]

this I understand, but are both factors measured in anyway?

 

[vleetx]

That is a good question,, as some of the uprights have a great volume of air (cubic foot per minute)and as long as that flow is great,, they have a good suction,,but interupt that flow,,and the blades capitate, and cannot flow the air, and you loose both the suction and the flow rate. I think that is one of the reasons Kirby beater bars are set low enough to keep the carpet from sealing itself to the head, and stopping air flow. I am sure more than one of us has experienced a kirby sucking itself to the floor and not moving,,even with a big push! Victor

 

[suckolux]

I know my Kirby had great air flow, it would pull cat hair across the floor from the edges of the nozzle, but not the strength of pull of the canisters. Have to guess its the size of the fan, spin speed, or compound fans that make the difference, I know the high air flow seems to work better for uprights,maybe large fans there?

 

[vleetx]

Most uprights had fans with huge blades,, so that dirt and other large things such as food and money could pass through them without too much harm.And they also have quite a bit of blade clearance to the case. When you look at a canister vacuum, the blades are much like a turbine,, very small, with very close tolerances, and spin at a much higher speed. So a lot of the time, a canister wont pass as much air,,but has more suction. The miele motors for example have real tight tolerances and give quite a lot of suction. Keep in mind, this is why when a bag bursts in a canister, and the motor digests a lot of dirt,, it usualy kills it. I have rebuilt two meile canisters, and in both cases,, they had sucked aquarium gravel in and through the motor. It just wiped out the bearings. Not to mention quite a fishey smell!