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  • #16
    A push and a shove

    Originally posted by tmc_31
    Arcane,

    .................................................. ...........................................

    Tiffe,

    Thanks, I became aware of the pressures involved after reading the specs on the Blackhawk Automotive Porto-Power website. Until I read that I had no idea that a hand pump would deliver that much pressure. Do you have any insight as to the results of trying to run two rams off of one mule? It seems to me that I should get the full 20 tons of force, just not full stroke as the mule will run out of fluid. Am I off base here?

    .................................................
    Tim
    Thanks Tim.

    Having two cylinders on one pump is a problem as the fluid will take the path of least resistance - ie the one that has the lowest resistive pressure. If that is the case, getting the cylinders to work precisely together will be a problem.

    I'd be inclined to have two independent systems as not only will the rams move quicker (ie don't have to share pumped volume) but will require double the oil for the same ram displacement. Twin/dual systems will give a lot more independent control.

    It is quite possible to connect two/dual rams to one pump and get effective independent motion and control, but I doubt that its worth it.

    Porta-Power rams are not all that heavily built due to the portability requirement and so are not all that long - particularly so at higher pressures and forces.

    My "Mechanics" porta-power (clone) set has cylinders that are rated at 2, 4 and 10 tons but they are pretty small.

    https://www.machineryhouse.com.au/Pr...stockCode=A364

    https://www.machineryhouse.com.au/Pr...stockCode=A367
    I have a 8 (long) ton - 8,000Kg - "air over hydraulic" ram on my 1 ton shop engine hoist. It is very solidly built and has a long stroke. All I need is a static oil supply and a 90 psi air supply. It works very well. Two of those may suit your purpose very well.
    I retro-fitted mine and as I have the original ram/cylinder,

    https://www.machineryhouse.com.au/Pr...stockCode=J032

    I could use them together as separate units as they are actuated/powered independently.

    This is my air-over-hydraulic unit:
    https://www.machineryhouse.com.au/Pr...stockCode=J033

    Cost AUD150 x 0.85 ~ USD130.

    The ends of both rams/cylinders are fitted for a yoke so that they act as "pin-pin" columns and are not restrained or acted upon by other than axial forces.

    The yokes are standard shop engine crane models that will be seen on most cranes and are easily, quickly and cheaply made.

    I hope it helps.

    Comment


    • #17
      Tiffe,

      Your point about the rams not acting evenly is well taken. I would rather not have one ram pushing too much and cock the top section over and make things worse. So two independent systems may be better. It should only take 2-3 inches of stroke to break these poles loose. I think the shorter rams will be more stable. Keep in mind that the rams will be strapped to either side of the pole. If the ram is too long I am afraid it could bow out under pressure.

      thanks,

      Tim

      Comment


      • #18
        Here's some random far fetched solutions. I assume the pole will be on the ground.

        Get a tiger torch, pressure washer, sledge hammer and a bottle jack.

        Place the pole on a support on either end. In the middle place the bottle jack. Start pressure washing into the joint with a soap mixture, then apply heat unevenly to one side of the pipe, hit with sledge and then pressure wash again. You can wiggle the joint up and down with the bottle jack. It sounds like a big job, so I am assuming there will be two big trucks. Attach one end of one truck, The other connect to the crane truck. It would be a real bonus if that truck had pulleys so the it's cable could be rigged low like a winch.

        Optional upgrade procedure, fill with gunpower while using Tiger Torch .

        Comment


        • #19
          Rancherbill,

          Sounds like either you and Boucher are in cahoots, or explosives are the universal remedy. I would not want to be in either truck when that thing came loose. It is bad form to get the hands hurt.

          I all seriousness though, the idea of using a pressure washer to force soapy water into the joint may have some merit.

          Thanks,

          Tim

          Comment


          • #20
            I'm glad I could contribute my own "random far fetched solution".

            I am happy that one of the five concepts presented had merit.


            I always think of the gunpowder solution. In Canada I can't get it, I don't have a firearms licence. I like the YouTube videos of creative uses for gunpowder. I paricularly like the anvil launching ones. I could envision a lamp post separation one. The thought of the end section of light shooting straight up in the air hundreds of feet is pretty appealing.

            Or you could make the worlds largest potato cannon and put a 100# sack of potatoes in at once. Just imagine the mushroom cloud of hundred of potatoes showering the area for a couple of hundred foot radius.

            Comment


            • #21
              Originally posted by rancherbill
              I'm glad I could contribute my own "random far fetched solution".

              I am happy that one of the five concepts presented had merit.


              I always think of the gunpowder solution. In Canada I can't get it, I don't have a firearms licence. I like the YouTube videos of creative uses for gunpowder. I paricularly like the anvil launching ones. I could envision a lamp post separation one. The thought of the end section of light shooting straight up in the air hundreds of feet is pretty appealing.

              Or you could make the worlds largest potato cannon and put a 100# sack of potatoes in at once. Just imagine the mushroom cloud of hundred of potatoes showering the area for a couple of hundred foot radius.
              I didn't know there were rednecks up in Canada!! Watchout World we're everwhere (and lookin fer sumpin to blow up)

              Tim

              Comment


              • #22
                I take it from the postings that you will not try to save the bottom section. Can you collapse it in on itself to deform and release it from the top? I've done this on similar applications, of much smaller sized stuff, though.
                Krutch


                Mentally confused and prone to wandering!

                Comment


                • #23
                  We had dozens of poles like that for lightning protection around the explosive processing buildings where I used to work. I watched a lot of them being installed, and I had a chance to talk with the project engineer handling one of the jobs.

                  Nothing was applied to the joints as the sections were lifted and slipped together. The PE told me the rocking motion of the wind on them would work them together so tightly that the joint would eventually become stronger than a weld.

                  Based on that, I'd say you're not going to have much luck getting them apart short of cutting them.
                  Any products mentioned in my posts have been endorsed by their manufacturer.

                  Comment


                  • #24
                    Did somebody already mention setting up two trucks, one with a winch- I'm also assuming the pole is horizontal, and you can set it up to stretch on it and wiggle it up and down in the center as Rancherbill suggested. I was going to suggest wicking in some penetrant as well- only difference is that I'm not going to suggest explosives though it would be fun-

                    What I am going to suggest is to forget about separating the sections and instead re-purpose the pole. If that were laying in my yard, I would have figured out how to install it vertically and mount a wind power generator on it. At the same time I'd have built a cable operated viewing platform that I could ride whenever the whim struck me. Then of course I'd have to have a lightning rod going skyward from the top, and then probably have some kind of tourist attraction contraption up there so the city wouldn't make me take it down
                    I seldom do anything within the scope of logical reason and calculated cost/benefit, etc- I'm following my passion-

                    Comment


                    • #25
                      Hey Guys,

                      Krutch,

                      I also thought about that. I could drill a 3/4 hole through both sides of the bottom section, insert a bolt all the way through and tighten a nut until the pole collapsed in on itself. My concern with this method is distorting the top section at the joint while doing this. I am going to have to install a new bottom section and then re-install the pole.

                      Winchman

                      I install these poles for my day job. The engineer is right, many times we will set the base section in concrete and then several days later set the top section on top of it. Usually, when the crane get off of it it is so tight that it is almost impossible to spin the top section for final adjustment. You had better have it right the first time. I have turned them, with great difficulty and with large tools. These have been in place for 6-10 years so I am sure that they are pretty well stuck together.

                      Darryl,

                      The bottom sections are damaged and for liability reasons not suitable for re-use. It kills me, but they are going to have to go to the scrapper.

                      Regards,

                      Tim

                      Comment


                      • #26
                        TMC,

                        Is the view of the Forum why you are saying that 20 ton is the max for Porta-Powers?

                        I used 50 ton jackheads daily in crane repair. I doubt that Enerpac has discontinued them, unless pu**ies have complained that they are too heavy. They damned well are, but sometimes you gotta use them, and sometimes they are not enough.

                        Hell, I even have a 50 ton bottle jack. They can be bought, too. Save the expense of an Enerpac pump, and useful where you can't get power.

                        Here is another example. When Westinghouse was still a going concern, 100 ton Enerpac jacks were used on each foot of turbogenerators to lift them to shim to align. ONE power source with valves to direct pressure to the jack that needed to lift. Units weighed 400 to 500 tons.

                        Cheers,

                        George

                        Are you involved with the company whose poles are falling down all over the country? I should imagine you are looking for an inexpensive remedy to this problem. I don't think anybody has been injured, yet, but, if I read it correctly, you have hundreds of those pylons, if not thousands, out there. I do not wonder that you are looking to do what you want at the least cost possible. You are in for a world of hurt, money wise.
                        Last edited by gmatov; 07-12-2010, 01:34 AM.

                        Comment


                        • #27
                          Tim,
                          Steve has the answer clear up in post#4, a sure and quick way, why are you not considering that?

                          Ken

                          Comment


                          • #28
                            I am thinking this is going to need more force than you're thinking. Forget portapowers. If I had to do that I'd weld blocks top and bottom both sides drilled for heavy clevis pins, and install 6" hydraulic cylinders on both sides for even push. Pin them at one end and just let them push on the other, so it doesn't bend the ram when the pieces come apart. Plumb them both to the same pump with 10000 psi hydraulic line.

                            Heat the outer pipe with a rosebud or two or three or four, and turn on the hydraulic pump. When the pieces are separated, scarf off the blocks if desired.

                            Comment


                            • #29
                              Originally posted by Ken_Shea
                              Tim,
                              Steve has the answer clear up in post#4, a sure and quick way, why are you not considering that?

                              Ken
                              Ken,

                              I have considered Steve suggestion, in fact cutting off the base near the joint then and slitting it for the inside is plan B. These poles have numerous penetrations so that it would be difficult to seal up and pump it apart hydraulically. Although I had considered that too.

                              Metalmagpie,

                              I have to do this with stuff that can be moved easily around the job site. Also welding to the top section will ruin the galvanizing and so is out. I am working out some push blocks that I can clamp to the poles (the machining part of this thread).

                              gmatov,

                              I realize that 40 tons may not be enough and that I can get larger jacks. I may do that. I am thinking two 50 ton air/hydraulic jacks (100 tons total). Do you know if these will work in the horizontal position. I have a 20 ton A/H I will have to try it horizontal. Yes, I am gearing up to repair these poles.

                              All,

                              Anyone have an idea how to calculate the force required? Sir John? Evan? Anyone?

                              Thanks,

                              Tim

                              Comment


                              • #30
                                tmc,

                                The jack head will work in any position. The pump won't but that is irrelevant.

                                The moment I read the above about welding to both pieces, I said that's a no-no, he is trying to salvage the major part of the installation, and they are galvanized.

                                Whether you can get bigger than 20 ton jack heads, see here:

                                http://www.enerpac.com/en-US/product...high-tonnage-0

                                50 to 1,000 ton, although 1,000 ton seems like it is on the large side.

                                Since you want to save the major portion of these stanchions, and they are made in a taper, are they not, it may be difficult to make push blocks that will grip the upper portion. It is tapered the wrong way. If you have a lip on the bottom edge to catch the joint of the upper section, it could work.

                                I assume your crimp roll makes them all to a close pattern?

                                Weld as you will to the bottom, throw away section, position 2 or 4 jack heads and go to town. You might need a couple 20 pound sledges on the lower section, or biggish soft faced mauls on the upper, to be saved. You don't want to mess up the galvanize, or you will be back in a couple years.

                                I know you can't say for litigation's sake what the problem is. Bad galvanize, lack of a weep hole, even bad steel. Usually, as far as I can see, such stanchions have a thick plate for a base, which should have a large hole in the base plate, so water buildup should not cause rust out. 4 all thread adjusting screws to plumb.

                                Ah, well, hope I have helped you a bit.

                                Cheers,

                                George
                                Last edited by gmatov; 07-13-2010, 02:24 AM.

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