Post driver hookup Case jx95

[SPYDERLK]

16 oz of fluid into a 1 in hose is going to produce how many GPM at maybe 7 to 10 cycles per minute.

You reckon that valve will handle that volume?

Yes. The valve is sized for its function.
tttt Bear with me here ... The HD 8 takes about a quart of fluid raising the driver 48". That quart is expelled back to sump in about 0.5 second if the driver falls without resistance ... and there are helper springs used to make it fall even quicker. Right there thats more than 30GPM average flow during descent. That isnt terribly much, but the peak flow, when it is going its fastest just before it strikes, will be around twice that [>60GPM]. A HD 12 will be at least twice again that much. There will be tens of PSI across even a large filter. It will slow the descent, compromising the strike, and in extreme cases will blow the filter.
larry

 

[RickB]

The effective displacement of the cylinder used on the HD-12 is about 20 cu.in. based on a 3/4 inch rod and 46 inch stroke as determined by my perusal of the description of the rod, cylinder and nuts attaching the rod to the machine as shown in the owner's and parts manuals. Cylinder bore does not enter into the equation as there is no full-diameter piston involved. A pint of fluid equals a little over 28 cu.in.

Larry is probably correct in estimating the flow rate at nearly a quart per second, I'd guess. But J_J's statement that only a pint of oil is involved seems accurate as well. We are talking about a small volume of oil leaving the cylinder in a very big hurry. It's no accident that the high pressure hose connecting the cylinder to the valve is either 5/8" or 3/4" hose. And it won't take much of a downstream restriction to blow the 1" return hose supplied by Shaver to pieces when the hammer drops. That I have seen first-hand.

Edit:
This post follows Larry's post #11 but was drafted prior to my seeing or reading it. I think we are both saying essentially the same thing.

 

[SPYDERLK]

The effective displacement of the cylinder used on the HD-12 is about 20 cu.in. based on a 3/4 inch rod and 46 inch stroke as determined by my perusal of the description of the rod, cylinder and nuts attaching the rod to the machine as shown in the owner's and parts manuals. Cylinder bore does not enter into the equation as there is no full-diameter piston involved. A pint of fluid equals a little over 28 cu.in.

Larry is probably correct in estimating the flow rate at nearly a quart per second, I'd guess. But J_J's statement that only a pint of oil is involved seems accurate as well. We are talking about a small volume of oil leaving the cylinder in a very big hurry. It's no accident that the high pressure hose connecting the cylinder to the valve is either 5/8" or 3/4" hose. And it won't take much of a downstream restriction to blow the 1" return hose supplied by Shaver to pieces when the hammer drops. That I have seen first-hand.

Edit:
This post follows Larry's post #11 but was drafted prior to my seeing or reading it. I think we are both saying essentially the same thing.

Yeah, I was wrong on the volume. Its about 1/2 what I said on the HD8 which has a 3/4 rod [I measured mine]. I would think theyd need more area to lift the heavier driver on the HD 12 tho. I dont know, but the specs would tend to indicate you would need more guts lifting ... and the flow requirements also suggest that a bigger rod area is being displaced. Also, too big a rod on a small driver would displace more fluid than necessary and thereby damp the fall of the comparatively lightweight ram. This all points to an error in the HD12 spec you are looking at. ... Either way, as weve said, there is a very high flow rate duing the latter stage of a fall and a filter is in the way.
Post Driver Specifications

 

[RickB]

Yeah, I was wrong on the volume. Its about 1/2 what I said on the HD8 which has a 3/4 rod [I measured mine]. I would think theyd need more area to lift the heavier driver on the HD 12 tho. I dont know, but the specs would tend to indicate you would need more guts lifting ... and the flow requirements also suggest that a bigger rod area is being displaced. Also, too big a rod on a small driver would displace more fluid than necessary and thereby damp the fall of the comparatively lightweight ram. This all points to an error in the HD12 spec you are looking at. ... Either way, as weve said, there is a very high flow rate duing the latter stage of a fall and a filter is in the way.
Post Driver Specifications

THe HD10 and HD12 use the same cylinder, part #SM1026. Assembly instructions call out 1-1/16 " and 1-1/8" wrenches to install the lock and jam nuts on the end of the cylinder rod. Standard nuts of that sze would be normal for a 3/4" threaded shaft or bolt.
My bad, the hose connecting the cylinder to the valve is 1" hose in both cases.
The other thing to consider is the volume and flow of oil leaving the cylinder is ADDED to the volume of oil passing through the valve and back to sump when the driver is conected to a functioning open center hydraulic system which the subject tractor has. At 15 GPM, that is another quart per second.

 

[J_J]

dao4ccl,


Do you have the other cyl for tilt? If so, then you are probably using the PB port. If the post pounder is in series with the 3pt, then the main flow is flowing through the series circuit, and the only fluid flowing out the OUT/return hose is the expended fluid.

Are you plugging into the remote valve if you have them?

Can you give us the hyd flow path on your tractor from pump to tank, including the post pounder.

How many full strokes can you get out of the pounder in one minute?

Someone else mentioned that they ran the 1 in return hose into a 3/4 fitting and then to the return circuit and everything worked OK.

When you get it all connected, would you do a short test by putting the return hose in a bucket and cycling the post pounder several times and let us know the amount and volume of fluid coming out that 1 in hose.

If you put a 1 in tee with gage in the return hose, that would tell the whole story. Just curious

I would be curious to see if the post pounder would pound a railroad beam with flat bottom into the ground. Some people seem to dig a small hole first or put a point on the wood beam.

I did watch the video.

 

[Timm250]

dao4ccl,


Do you have the other cyl for tilt? If so, then you are probably using the PB port. If the post pounder is in series with the 3pt, then the main flow is flowing through the series circuit, and the only fluid flowing out the OUT/return hose is the expended fluid.

Are you plugging into the remote valve if you have them?

Can you give us the hyd flow path from pump to tank.

How many full strokes can you get out of the pounder in one minute?

Someone else mentioned that they ran the 1 in return hose into a 3/4 fitting and then to the return circuit and everything worked OK.

When you get it all connected, would you do a short test by putting the return hose in a bucket and cycling the post pounder several times and let us know the amount and volume of fluid coming out that 1 in hose.

If you put a 1 in tee with gage in the return hose, that would tell the whole story. Just curious

I would be curious to see if the post pounder would pound a railroad beam with flat bottom into the ground. Some people seem to dig a small hole first or put a point on the wood beam.

I did watch the video.

I have an HD10 & it will drive a RR tie with a square bottom in clay with no problem.

 

[dao4ccl]

Thank you all for your responses and input. I attached the Case manufacturer suggestions which we have not followed yet and may not. We were able to order a metric threaded hydraulic fitting to fit the fill hole and a few other fittings to reduce the 1" hose down. The pounder is working well, about 15 posts done. The fittings do reduce the inside diameter at the fill hole to about 1/2" which, I do not like. The plan is to use a short threaded pipe at the connection to the fill hole as it will have a larger internal diameter. Took about 30 sec to drive a post about 3' in the ground no rocks, and about 2 min for a post that hit some rocks. Certainly better than by hand Now I need to buy more posts. Will post a few pics of stuff later.

 

[J_J]

dao4ccl,

I am still curious about the pressure on the return hose. If you get a chance, would you put a hyd gage on the return hose at the filler cap and let us know the pressure, whether the pressure builds and peaks or averages out.

Which fluid is flowing into the return hose, is it total valve fluid, or is it only the cyl expended fluid?

The number of strokes per minute may vary the return pressure.

Thanks