Anotherpower.com Forum
Project Journals => Users Projects => Topic started by: tomw on May 04, 2012, 02:16:18 pm
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The recent crash of my 12 footer caused a mast bend. Weld appears 100% but the 2 bottom tubes are tweaked:
(http://pics.ww.com/d/447620-1/100_5106.JPG)
Curiously, the tube looks like it was supported on the ends and bent down in the middle. It has a dip that is about one inch off straight according to my string line.
(http://pics.ww.com/d/447605-1/100_5101.JPG)
I do not have a functioning torch due to the cost of bottles and infrequent use which makes it too expensive.
In another thread BJ suggested a wood fire might let it settle back to straight. With that in mind, I have literally tons of firewood on hand ready to burn.
I was thinking I could build a bit of a "kiln" from bricks, rock and dirt to direct the fire onto that area and support it near the bend on the base end then set up a support at the other end to stop the sag at or about straight, loosen the hoisting cable fire up the fire and feed it until I get the thing relatively straight.
Does that sound feasible?
I also have 2 smallish charcoal kilns I use for melting aluminum but they are heavy and the heat will be concentrated in too small an area for supplying the heat over a wide area needed for this.
I figure it does not need to be laser straight and just straight enough to keep the load centered over the column?
Ideas, criticism or tanks of O2 / acetylene graciously accepted :o
Thanks.
Tom
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Sounds like this might be a job for a "Beverage Meeting".....its got the makings, eh? ;) Wish I lived closer, I'd give ya hand, Tom (and supply the adult beverages....)
Bill
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I would not heat it at all, that will soften the metal, I would add a set of guy wires at the bend, and put it back into service, if you are concerned about it, then weld some flat bar extending about 3' either side of the bend.
PS:
If anybody is bold enough to comment on the bend just tell them it is in preparation for the earths poles flipping over, if it happens to be 90 deg to N or S just tell them it is proof positive that the poles are changing. Then berate them for being so ill informed that they did not know about the pole change over every few billion years, and just to rub their noses in it ask if they are global warming believers.
allan
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Just thinking out loud here..
Maybe there's a guy with An oxy-acetylene rig somewhere in your neck of the woods that might like to trade for a cord of firewood. Probably need a big rosebud for that size of pipe tho...
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Do you have or know someone who has a good size and length of I-beam. You could place the beam under the tower, use plenty of straps on both ends of the beam to the tower and place the largest bottle jack you have at the bend. Use a slight larger piece of pipe, cut in half, as a cradle and support the bend. You could then pump the jack and begin watching the bend push up in increments and move the jack as needed to straighten the pole.
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This is what I'd probably do.
I would not heat it.
I would weld another pipe/rod/whatever across the end to make a Tee. This will be used to turn the pipe so that the bend faces up or down, but cannot turn as we press on it with whatever.... It stabilises the pipe orientation.
Once thats done, If I had a decent tree available (and you do), I'd chainsaw out a slot that would take the end of the pipe and the cross piece. This will allow accurate setup of the pipe orientation. It can be blocked up either end of the T within the tree slot to make it so that the pipe cannot rotate, but instead will remain faithfully in the orientation we place it.
Then, if you place the pipe in the slot, with the bend downwards,.... park the truck above the other end, bottle jack in the middle, and pump it to true... repeat until it remains true.
If you over doo it, then simply rotate the pipe 180 degrees and do it again.
It will need a length of timber between the jack and the pipe to spread the force.
This will work, and with the most basic of things, you have full control of bend and angles. Just need a decent tree to give the stability. If you have tractors as well then it's lots easier, may not need the tree.
[attachimg=1]
...............oztules
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Oz;
Of all the ideas I like this best. after Alan's advice to leave it bent and guy it at the bend and just ignore complaints.
Things that are not plumb, level and square bug me so I want it straight.
It is already anchored on the base end to a deep, flared footing that will not pull out. I can anchor the top under the truck and jack it at the bend with a floor jack I have onhand. The base attachment will both anchor and keep it aligned against rotating. Build a saddle to spread the jacking pressure so it doesn't crush the tube which is not very heavy walled. Something like 1/8th inch X 6.75 inch tube.
Thanks to all for the input.
Tom
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Tom,
Don't forget to put a groove in that saddle so it doesn't slip under pressure. A few shallow passes cross ways over a table saw should do it.
Kevin
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This is what I'd probably do.
I would not heat it.
I would weld another pipe/rod/whatever across the end to make a Tee. This will be used to turn the pipe so that the bend faces up or down, but cannot turn as we press on it with whatever.... It stabilises the pipe orientation.
Thats exactly what I did to get the kink out of my pole. Welded on a cross piece and then drove the tractor up it :) Cleaned up with an angle grinder.
Since mine was not due to a blade strike (due to whip during a very gusty storm), I put and extra set of guys on to keep it straight.
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Well, I used a floor jack the pickup and some blocking and got the mast pretty well straight. Took it a little past straight and when the pressure was released it relaxed back about as straight as could be expected. At the height of the process both rear wheels on the Dakota were off the ground. The base is held in solidly in deep, belled concrete pillar. It did not move a bit.
I backed the truck up until the spare was over the end of the 2 welded sections as I didn't want to stress the upper home made coupling in the process. Then eyeballed the worst of the bend and stuck the floor jack under it and jacked it up until the truck was suspended on the end of the tube. Let it hang there until the wheels settled to the ground. Repeated a couple times until it was a bit past straight and viola, it was straight as I could make it. No fire, no torch and only a little sweat. It was 80 F after all.
Thanks for all the advice.
Tom
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Sounds like a fun and effective fix Tom.
Good to hear your tower is back in operable condition again, cant wait to see what you put on it.
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That's my kind of heavy tooling: Floor jack and
Truck Little car.
For bigger jobs, I add a BFH and plenty of cursing. Might not help the project, but it makes me feel better. ;)
G-
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Alls well that ends well.
Good job.
...............oztules
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OK, hoisted the main mast up to check stuff.
Looks good to go. A few checks and a modded top stub and she will be ready for the other turbine.
(http://pics.ww.com/d/448799-1/100_5122.JPG)
(http://pics.ww.com/d/448802-1/100_5123.JPG)
(http://pics.ww.com/d/448805-1/100_5124.JPG)
Above, it is not plumb but not a problem just a tweak to turnbuckles will get it plumb.
(http://pics.ww.com/d/448808-1/100_5125.JPG)
Just a share.
Tom
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Looks good Tom, even passed the ruler on the screen test. ;D
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Well done but, you will be adding a 3rd set of guy wires won't you!
The top set tries to hold back the the force on the turbine, the next set down is the pivot point, the third set opposes the force from the top set/turbine.
Unless one has a tower of enormous cross sectional area the minimum is 3 sets of guy wires.
Think, tower base anchored to the ground by lots of concrete, Tom has a jack in the middle, top is anchored under a vehicle, three points, why should it be any different for an erect tower?
I know the damage was caused by your tower falling but! Base is anchored, top has weight of turbine plus tower weight, tower falls encountering a piece of ground that is higher than a straight line from base to top of tower once it comes to rest, resultant, tower bends beyond it's moment of elasticity, outcome a bent tower. (OK ignoring the turbine damage)
Allan
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Allan;
Yep, it has a weird tower stub on it in use. Very beefy heavy iron with a 2 7/8 inch tube for the yaw tube to slip over and it sticks up 10 feet above what you see now. I am just going to make a slip over adapter to match the (smaller) yaw tube on the 8 footer that is going on it or maybe weld on a bigger yaw tube to the head? I intend to eventually add another 11 or maybe 22 feet to it as I have 2 more lengths of that steam pipe in my iron pile. Just need to make some coupling sleeves. That will get me up around the 65 plus feet mark for the 8 foot fiberglass bladed dual rotor. So additional guy lines will get added and a wider footprint for the upper cables ansd a shorter upper stub just long enough to clear the guys.
Slowly getting stuff sorted out and, if I can't sell the 12 footer head I might have to put it back up and bite the bullet on having to do maintenance.
Tom
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Tom maybe I did not make my point clear but you need at least a third set of guy wires, the fact that you have used boiler tube shows in your pics but the point of what I was trying to say was about bending moments.
Allan
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Tom maybe I did not make my point clear but you need at least a third set of guy wires, the fact that you have used boiler tube shows in your pics but the point of what I was trying to say was about bending moments.
Allan
Allan;
I guess I don't get it?
Please elaborate and maybe "why?
Thanks.
Tom