Show us your Arb Diggers please.

[Bogoak]

4 hours ago, openspaceman said:

My experience is quite out of date now but even then they were a bit of a kludge. At the time Hiab loaders from lorries were being adapted for more off road uses, one of the problems was that lorry loaders tended to work on the flat and so the slew function didn't need much force or pressure. Once you were working on sidling ground and were swinging a load slightly uphill the slew rams couldn't cope so intensifiers were used in the circuit. Later better solutions like tandem slew rams and levelling king posts on purpose built machines made the use obsolete.

 

They may still have a niche, I envisaged using one alongside a regenerative function  on a splitting ram where the only power was from a simple gear pump, this would allow three increasing forces as the ram encountered a tougher log to split. Plainly there are trade-offs and the obvious one is that the ram will work slower to gain the extra pressure, as Eddy says. So whilst one wouldn't buy a machine to run a high pressure ram than the hydraulics could supply if you already have the machine and want to use the high pressure cutter then it becomes possible. Of course the hydraulic components downstream of the intensifier need to be capable of resisting the higher pressure than the rest of the equipment has to.

 

 

You have to select an intensifier ram so that the ratio of piston area to rod side area is the inverse of the pressure available to the required pressure. In the case Eddy specified  the piston side to rod side ratio needs to be 250:190 and the stroke on the rod side has to deliver  enough oil to  fully operate the high pressure ram. The rod of the intensifier just moves in and out and is not attached to anything. In practice you will need a diverter to occasionally  reset the intensifier ram if there is any creep or oil loss

Ah, thanks. Simple enough........ in theory.

[Stephen Blair]

[green horn]

cracking machine [emoji108]loved workin alongside a 4cx doing tree work was nothing it couldnt do.

[steve30]

Hi folks
Yanmar BV25 2004

The ignition warning buzzer has started to stay on, so turn the key to the left pre warm buzzer goes off, turn right engine starts, but now the buzzer is staying on, no other warning lights, it only started today after we washed the machine, no problems before hand 

Any ideas gent 

Thanks in advance 

[monkeybusiness]

Does it indicate low oil pressure? Check connections to the pressure switch (and make sure there’s oil in it!) 

[dig-dug-dan]

2 hours ago, Stephen Blair said:

Stephen, in the fourth picture, what is that silver box mounted inline with the hydraulic pipes on the ram? I saw those today on a kubota and wondered what they do?

[Stephen Blair]

I think they are relief valves.

  If a pipe blows then the arm won’t drop.

[Stephen Blair]

3 hours ago, green horn said:

cracking machine loved workin alongside a 4cx doing tree work was nothing it couldnt do.

4cx is the dream!

[monkeybusiness]

43 minutes ago, Stephen Blair said:

I think they are relief valves.

  If a pipe blows then the arm won’t drop.

Check valves mate - they have to be fitted if the machine is used for lifting operations. 

[Matthew Storrs]

Any JCB anoraks out there? Could you tell me whether this is project 12 or project 21? It’s a 4 speed power shift gear box and year 2002 which was the changeover from project 12-21...