What size hose to use for 28 gpm?

4570Man · Jun 26, 2017

The title is pretty self explanatory here. The options are pretty much 1/2 or 3/4 ID. I would go with 3/4 except the pressure rating is lower and it's cutting it pretty close.

RickB · Jun 27, 2017

For constant flow applications such as an orbit motor 3/4 is a better choice. If the hose you are looking at is rated higher than your system relief, buy it. If the hose you are looking at isn't rated properly, find a different hose. It's not difficult.

oldnslo · Jun 27, 2017

28 GPM thru a 3/4 diameter hose is around 38 feet per second flow velocity. If this is constant flow that will create heat and possibly aerate the oil due to the turbulence this velocity will create.

LD1 · Jun 27, 2017

3/4" would be minimum. What pressure you running at?

3/4" R2 and R16 hose is ~3100psi range. Or some of that tough cover (abrasion resistant stuff) is 4000psi+

1/2" hose with 28gpm.....might as well drop it to a 22gpm pump.

jenkinsph · Jun 27, 2017

4570Man said:
The title is pretty self explanatory here. The options are pretty much 1/2 or 3/4 ID. I would go with 3/4 except the pressure rating is lower and it's cutting it pretty close.

Really the options should be 3/4" or 1" depending on length of hoses and number of fittings and their losses. For high pressure applications in larger sizes you may need to step up to 4 wire hose.

Forget the 1/2" hose for this application it simply is too small.

Todd727 · Jun 27, 2017

What size fittings are you using? They are probably going to be your limfac.

4570Man · Jun 27, 2017

The cylinder is 3/4 o ring boss. Valve is probably 3/4 pipe. Aside from that it's all up in the air.

RickB · Jun 28, 2017

4570Man said:
The cylinder is 3/4 o ring boss. Valve is probably 3/4 pipe. Aside from that it's all up in the air.

If the use is a cylinder, use 1/2" hose. The flow interval isn't long enough to create any heating problems. See my post #2 above. Your port size is the limiting factor anyway.

Now all the armchair theorists and fluid engineers here can flame away.

LD1 · Jun 28, 2017

Correct. Heating wouldn't be my concern. Speed would.

Hose needs to flow MORE than 28gpm.

Depending on cylinder and rod/bore size, on retract, if you are cramming 28gpm into the rod side, significantly more gpm is coming out the base port. Probably closer to 40gpm.

As said, 3/4" minimum. 1" better.