Need help with hydraulic hose sizing for 5 spool control valve?

[chad22]

I bought this hydraulic control valve BLB - BM20/5 - 5-Spool Control Valve - eBay (item 320295452598 end time Nov-23-10 12:31:17 PST) on ebay and need help figuring out the size of hoses I need to connect to it.

What does the following mean?

(#8 SAE I/O ports. and #6 SAE work ports) So with that what hoses do I need? And where to get them? I'm building a mini backhoe.

Thanks

 

[dfkrug]

Are you using plans, or your own design?

That's a pretty small valve.....I gather your pump will be delivering
maybe 3-5 GPM? If so, 3/8" IN and OUT hoses are fine, and work port
hoses, 1/4".

Those sizes are for the adapters. A #8 SAE is a 1/2" O-Ring Boss (ORB)
female port, for example. (#8 means 8/16 inch.) You should buy hoses
with JIC #6 ends and buy JIC-to-ORB adapters for the ports.

Some of these home-built hoes, like my CADDigger, used manual outriggers;
if you are planning hyd outriggers, you will want a 6-spool valve.

 

[chad22]

Thanks. I'm using my own plans. I'm building it off a riding lawn mower. I have 3 trenches to make this spring and don't want to dig with a shovel anymore. :laughing:

For now I think I will use manual outriggers and later upgrade to hydraulic ones.

I've already made the bucket. I cut the metal for it a bit crooked, but said heck it will work. :laughing: I did try to straighten it up a bit though.

 

[Lt220]

Your input and output ports with be a #8 thread which is basically a 1/2" thread with an O-ring. The work ports will be a #6 thread which is basically a 3/8" thread with an O-ring. These threads are NOT pipe thread so don't get confused and think that standard pipe thread will fit these ports. You can buy your hoses online at a hydraulic supply such as surplus center. If you are lucky, you may have an industrial supply store at or near your location that can make your hoses for you with the correct fittings crimped-on the hose. I have a local industrial supply store that makes all of my hose for me. I just tell them the length and what type of fitting that I need and they make it. Different stores, such as Tractor Supply and Northern Tool, will have hydraulic hoses of different widths and lengths in stock. Most of these hoses have standard pipe thread fitings installed on both ends. These stores will also have the adapters and fittings to adapt the pipe thread on their hoses to what ever type of thread you need. I would recommend that you go ahead and assemble all the parts for your backhoe project and install the SCV where you want it and then determine how you want and need the hose. With all the parts assembled, you will be able to get accurate measurements for the hoses and also be able to determine if you will need your fittings straight or on a 45 or 90 degrees. This will save you allot of headache and money because dealing with hydraulic hose and fittings can be VERY EXPENSIVE!

 

[kennyd]

Here is a thread chart I use: Hydraulic Warehouse - Size Chart

Use 3/8" lines for your IN and OUT ports from the pump, and 1/4" lines on the work ports (The lines from the valve to the cylinders)

 

[J_J]

I believe that valve has a flow capacity of 6.6 GPM, and is tandem center.

Technical characteristics: BM 20


Nominal flow 4.5 GPM

Max. flow 6.6 GPM

Nominal pressure 3600 psi

Max. pressure on ports 4700 psi

Max. pressure in tank-line 1100 psi

 

[chad22]

Thanks for the help everyone. :thumbsup: The valve should be arriving in the mail today. If/when it does. I'll head into Tractorsupply and pick me up some hoses.

Once I find my charger to my digital cameras batteries. I'll take pictures of the backhoe when it's done.

I have a whole gallon of International Harvester paint, that I found sitting next to the town dumpster. I'm gonna get out my spray gun and and shoot some of that paint all over the riding mower.

The mower itself needs a paint job anyway. So I figure I might as well use the paint up and give it a good paint job.

 

[chad22]

I went to tractorsupply to get some of the hoses. I still need to get the adapters as they didn't have any in stock. But I'm just ordering those off of ebay.

I have another question. On the in and out ports does it matter which hose goes where? Or does the suction hose have to go in a certain port and the return on the other?

I just don't want to tear up my valve by hooking the hoses up wrong.

Thanks

Chad

 

[J_J]

Suction hose is associated with a hyd pump. The pressure line from the pump should go to the IN or P port on the valve.

T or tank port should go to tank/reservoir.

 

[chad22]

Suction hose is associated with a hyd pump. The pressure line from the pump should go to the IN or P port on the valve.

T or tank port should go to tank/reservoir.

Thanks for the help. I didn't know what the T and P meant. "Although now thinking it should have been obvious to me". And I didn't want to hook it up wrong and blow out the valve or something.

Chad