AREA |
LAST COUNT DATE |
COUNT |
CHANGE FROM PRIOR COUNT |
DATE OF PRIOR COUNT |
CHANGE FROM LAST YEAR |
DATE OF LAST YEARS COUNT |
UNITED STATES |
5/17/13 |
1769 |
+0 | 5/10/13 |
-217 |
5/18/12 |
CANADA |
5/17/13 |
118 | +5 |
5/10/13 |
0 |
5/18/12 |
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5/17/13 |
52 |
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5/18/12 |
INTERNATIONAL |
04/2013 |
1301 |
+33 |
3/2013 |
+123 |
4/2012 |
World Oilfield Forum
Can anyone help me with SkyTop Brewster n-75 drawworks brake adjustment. This thing kicks like a mule. Have tried about anything you can think of. Will stop on a dime and bands seem to roll off drum right just a brutal kick.
Views: 764
Permalink Reply by Wayne Nash on It seems to be the nature of the beast... Every one I've been on kicks like a mule.
Permalink Reply by Thomas R Davis on Check your front pad on brake band,and how the drawworks is bolted to the sub base, or cross chained on the front if its too tight or the sub is not level it will bow the drum shaft and throw the brakes off it doesn't take much to it out.
Permalink Reply by Jay Brown on I love to run a N-75/BDW 800 (same thing). First one was in '82 and being a U-15, 50/75 Nat young driller, I thought it was a close to running a space shuttle I'd ever get. They all do have a tendency to kick and I've always figured it is from the lack of rigidity (stiffness) of the bands used in Brewsters and that sexy, light brake handle that looks like it come off a pull'n unit (versus that pump rod thing that National uses, sorry Curtis). The difference in changeing brakes in these drawtools and a National is great. You can just bend them around and a National was always a struggle. Most of this is basic brake adjustment, but steps are missed sometimes and its critical to get these brakes right. Curtis called me on this and if I repeat anything you've done, chalk it up to all the young Drillers/Derrickhands I've trained to do this.
First thing, in these drawtools they have a scribe/safety plate welded under the balance beam. When adjusting, don't rely on counting threads. If you scrape the grease/tar/nasty stuff about 6 inches inboard of the adjustment bolt you'll find it. You have to either get in the hole from under or take the front off. Don't have to be perfect, sticking fingers in to check level is 'bout good enuff. If you're not adjusting brakes, do the rest and check it later. Even if one side is newer, that measurement is where you fix it.
Second and what I've found, is the MOST important. Adjust the rollers and make sure they move/roll freely. Specs are somewhere around 3/16 and I've always used 2 hacksaw blades on the easy side. 9 out of 10 times, a kicking situation comes from these being too loose. This is so important, if all the steps don't work-check 'em yourself. These keep the band from flexing/bending on release (clutch'n) and that is where the kick comes from. All ideas tell you to back 'em off, but it makes it worse. You stated that they were free, but the same movement on top is not getting all the way around. The movement has got to get all the way around the drum even and these rollers push the slack from the bottom for complete release.
Third is, due to the current ban of asbestos, they need more powder than a junkie on a holiday. I like fine, dry barite. Fullers earth is not as abrasive enough to get all the polish I want. Turkey dusters are fine, but handfuls in the top cracks while drilling seems to find its way around. If its jack'n off while drilling, barite will cure it. Your auto driller and the directional staff will hug you for that smooth glide while drilling.
Fourth is the springs. Don't get them too tight. I've found they have more to do with brake handle weight (feel) and that middle tightness in handle lift. When the rollers are right, It runs just fine without them. In fact some bands come without a place to hook the springs. I always b!tched till they welded them on. I start with the same 2 hacksaw blade adjustment in the middle of the springs and crank them till....it felt right. If they are too tight now, you might back them off some till you get the rollers right. If you get them too tight, the middle of the band drags and you get that kick again. Not sure what Billy Dan says here but, I found its Driller's preference after a little load for unwrap of the bands.
Did I mention the rollers and that I really had an affection with this drawworks? After all the AC/Omron train'n I been doing, I got this (I hope).
OBM pay on Xmas day, Thanks,
Jaybird
Permalink Reply by mike on I appreciate all the feedback. Jaybird that is very detailed and thank you. We are still haven issues and upon looking at schematics we noticed the difference in brake handel angel and linkage. It seems as if there is a differernce in n-75 brewster and n-75 skytop brewster(which is what is on my rig). I have located right assembly and am hoping this will cure some of the problem. It makes since as tabs on brake bar going to band seem to be to short and when brake handel is raised it seems to bend front of band before it actually (kicks) rolls off drum. We have not been able to run front rollers anywhere near band as it would not allow band to come off drum at all. Due to the bending of the band. Once replaced I will use your system Jaybird.Hopefully this works and I will let you guys know.
Permalink Reply by Wayne Nash on I've been on a lot of Brewster rigs, and in my experience they all kick like a mule... I can't see any difference in the design, or way of adjustment that makes a difference.
Only thing I can say is; Don't stiff-arm it, it'll throw you over the console...
I've been running a U-15 for the last 3 years and it always kicked like a mule until we reworked the whole brake system, had to re-align the adjustment bar, redo all the rollers, and replaced all linkage and everything, still kicked like a mule until we finally got the rollers adjusted just perceftly right, but you have to stay on top of them or it will get to kicking again. I used a nickle to adjust my rollers. I also liked to use a little soda ash before I put bar on them, seemed to work pretty well for me. Not to mention the little jewel isn't made to go 11,000 ft either, so breaks didn't work the best anways, so if you do take her a little deeper than made for, you better be a big boy or have help there with you while making connection or tripping, and two tong heads for 8" collars to hang off the brake to drill with!!! Gotta love the antiques!!!! I like our new national 610 a lot better, sweet little drawworks.
Permalink Reply by Matt Cantu on © 2013 Created by Drilling Ahead.
