Hose diameter/QC diameter question

[nickel plate]

I'm in the planning stages of the hydraulics for a FEL grapple thumb which has one operating cylinder with two 3/8" ports. Should I then use 3/8" hydraulic hose? If I use 3/8" hose, do 3/8" QCs allow an equal amount of fluid through them, same as the 3/8" hose or if less, should I step up the QCs to 1/2"? There will also be several 90 degree ELS piped in.

 

[J_J]

Although the step up is recommended, I doubt that very many people do it. There isn't that big of a loss anyway.

If you had a continuous flow , like to a hyd motor, it might be a good idea.

 

[kennyd]

I'm in the planning stages of the hydraulics for a FEL grapple thumb which has one operating cylinder with two 3/8" ports. Should I then use 3/8" hydraulic hose? If I use 3/8" hose, do 3/8" QCs allow an equal amount of fluid through them, same as the 3/8" hose or if less, should I step up the QCs to 1/2"? There will also be several 90 degree ELS piped in.

For a grapple/thumb, anything bigger than 1/4 hose is a waste of money, and the 3/8" is harder to route as well. The small cylinders used on them require very little flow. 1/4" QD's will suffice also, but you can use 3/8" also if you want. The amount of 90's is irrelevant since the flow is only intermittent.

 

[Discount Hydraulic Hose]

You should be able to get the maximum allowable flow rates from your coupler supplier. As long as the couplers you are considering allow enough flow for your application, upsizing shouldn't be necessary. If you're planning to use ISO 5675 Agricultural Hydraulic Couplers (aka "Pioneer" Couplers), here are some examples of flow rates from DiscountHydraulicHose.com.

1/4" Coupler = 3.2 gpm
3/8" Coupler = 7 gpm
1/2" Coupler = 12 gpm
3/4" Coupler = 20 gpm
1" Coupler = 40 gpm

If swapping attachments, or compatibility with other equipment is an issue, the 1/2" couplers are by far the most common size. We sell more of those than all other sizes combined.

 

[J_J]

AKKAMAAN posted this link for hose size. Enter your GPM in the green area, and see if your choice is logical.

If the ports on the cyl are 3/8, and the valve ports is 3/8, then go 3/8 hose, and 3/8 QD's.

https://spreadsheets.google.com/ccc?key=0AgccLk48zZpwdHJSRm95bnFGZV95eDBMV05aSUZxTmc&hl=en