I am wanting to mount a BMS_L 125 Seppi mulcher on a 2002 SK160LC Kobelco excavator and would like to talk with someone who has been around the mulching biz or someone who has knowledge about installation. I purchased head used and it was on a JCB, so i couldn't copy that layout. I know Kobelco sells complete kit but it's pricey. What is the company to go to that can provide a priority flow valves and click-on click-off switch ect? I have the piping and can make what i don't have. Any help would be great!
hkx is one company california I think ,hydraulic circuit technology they are around atlanta I think
I sent all my info to hydraulic circuit tech and they returned with a $6800. quote, 7 days build time for the electric operated priority flow valve and the switch inside cab to operate it, no hoses, no pipes. I checked Rexroth 24 volt electric priority flow valve prices and they are around $1500. but i don't know exact size i need. ( just made me wonder where the $4300. was going) I have saw a diagram off a installation of the flow valve, it goes between pumps and valve banks. With a electric signal from switch inside cab the flow valve has priority to send oil to mulcher when switched on.( on-off switch is $125.) Priority valve is adjusted until main boom begins to slow when raised, this is point at which no more oil can be scavanged for mulcher. Mulcher motor has an adjustment to set it with available oil flow from priority valve for rpm setting. Kobelco wants $9500. These are off the shelf parts that if i just had correct part # and a person that has installed befor could walk me right though this installation without giving away several grand. I am having to install it anyway.
I'm assuming your wanting to install the priority valve to help maintain a constant head speed. How much mulching are you planning on doing? If your only doing a little, I would just install a stroke limiter for your aux circuit and work that way. You will get some head speed change as your working. I don't agree with your plan to set the flow to your mulcher. You need a flow meter to set this. The reasoning is because you can send way more flow than your motor can handle. This can cause your motor to fail. The speed adjustment on your head motor is your displacement screw. It is meant to be adjusted, if your oil flow is with in spec. In regard to your flow divider, it has to be able to handle the flow and pressure your putting through it. So it need to be a fairly large one, that can take 5500psi or so. Its very simple to install, just go off of pump 1 to priority valve. From priority valve you will send one hose to the main control valve, and the other hose to your aux line. With that being said, I have had some problems with these priority valves. I have seen where they cause miss tracking and other issues. The ones I have rigged up, we used a danfoss valve, pvg32 or pvg120. (Just google it) Depending on your oil flow in spec. There is many options, so you need to make sure you choose the correct configuration for your application. Not sure your flow spec you need for the head. This valve is pressure and flow compensated, so you will maintain a constant head speed. You feed this valve from your aux port A, and return it to aux port b. So since it goes through the main control valve, it doesn't cause any other hydraulic issues.
I thank you for advice. The head oil flow range is from 20-40 gpm at 250 bar. The kobelco has two pumps producing up to 80 gpm at 5000 psi max. They only mentioned priority flow valve because that was the only hydraulic part other than plumbing mentioned in the Kobelco parts quote. They called it an electric controlled priority flow valve with an adjusting procedure in which all oil went to main valve banks, then oil was diverted to mulcher up to the point it began to have effect on main boom raising. That was all extra oil flow available to run mulcher. As far as over loading mulcher motor with oil, with flow control valve adjusted properly, there should be no excess, it should just run though valve bank as it does now??
I certainly will look into you idea and am not disagreeing. On a machine as small as mine do you think coming off just pump one want cause problems with other functions? That would be like taking 100% from that pump right? If Kobelco would just sell me this one part out of kit i would be set, but i haven't gotten them to return my messages after i couldn't see paying, over $7000. for the hoses in the kit, i have all the piping and 4-wire hoses. You know a sk160 is not a large machine.
All I was getting at, is you have no idea how much flow your sending to the mulcher head without the use of a flow meter. You could be sending 10gpm or 40gpm. No real way to tell without the flow meter. And yes, if your priority valve is adjusted properly, then the excess flow will end up going to the main control valve. Also, if your "priority valve" is after the main control valve, how is it a priority valve. Doesn't sound like the priority valves I have seen. If you were to install a priority valve off of just one pump, it would cause hydraulic performance issues. You need to find out how much flow your auxiliary circuit is rated for. This would indicate your max aux flow, without causing issues. It almost sounds to me like you don't have any auxiliary hydraulics at all yet? If this is the case then you will have to buy the parts from kobelco, as that is their proprietary valve.
I see the engine on that size machine is about 112 horsepower. That means you 80 GPM would be at free flow. That would indicate a max flow of around 30 gallons a minute at 4,000 PSI and your engine would start dropping RPM. As I recall the mulchers I've put hands on ran at a round 2,000 PSI so that could double flow to around 60 GPM but you also have to run your machine. We used to put diverter valves on each pump and then balance output with a flow meter. A switch on valve was next and then outflow to the head. Problem is you have to stop running any machine functions to let the mulcher spin up but when you operate another function the mulcher slows down. The operation became like a hot saw feller buncher. It spins up and then you slow it down booming into the brush. The other problem running them was that the excavator cooling wasn't enough to cool off all that flow. We almost always had to run a supplemental cooler on the return side to keep from over heating the machine.
Mr GaryHoff, i looked at a diagram from a hkx kit for a machine very close to the size and layout of my machine, they wouldn't show me exact parts or numbers cause they want to sell a kit. The priority valves were after pumps befor valve banks, they had adjustable flow/pressure controls. They are set close to my heads oil needs to keep from over supplying, there is a process to fine tune after oil warm up, so no sending oil to the head blindly. The priority valve hooks to both pumps and is turned on by a click on off switch in cab,i am sure i will have to buy kit but there is only 3 main parts and from rexroth these parts are only 1/3 of kit cost, i am just paying for correct valves they install, that is why i am here hoping someone has done a sk160 kobelco befor. Mr John c. you are correct on machine on your h.p. oil flow. The head states it requirements are it needs 13-39 gpm @ 2200 psi. I ran the JCB 190 head was on and i am sure it did effect some of it's fuctions but i have never operated a 190JCB befor anyway. I am almost positive there will be heading issues but my customers are hunters, needing shooting lanes kept widened and farmers needing the willows and gums cut back in wetlands so pivots want drag over them. Spraying has became a problem in these areas. I am going out on a limb to keep clients happy and i will make it work, so thanks for all the help.
have you thought about putting an auxiliary power pack on just to run the mulcher
I reckon the best way is to mount a hydraulic transmission pump at the front of the engine and plumb it as a closed loop system. The benifits are that you only need one engine, keeps the machine compact, no need for extra cooling package and the machine will work better and faster than mucking around with priorty valves etc. The only down side is that you HAVE to join the 2 main mulcher hoses when not using the mulcher for a long period or it will destroy the charge pump in the trans pump