View Full Version : Pump shaft, kind of...

Col Mckee
02-05-2006, 08:20 AM
I am making a water swivel for a small drilling rig with which I plan to drill a well in my back yard. The swivel allows water to be introduced into a rotating pipe (drill stem) under some pressure. I am basically copying a swivel which I bought some 25 years ago and have used in underground horizontal boring for those same 25 years. What material would any of you suggest for the rotating shaft? It needs to be easily machinable: cross drilled, bored 1" for half its length and threaded both ends and precise enough in (undisturbed) O D to seal with off the shelf seals. Shaft O D will be 1-1/2" and will rotate at about 150rpm. Torque could get severe if rock is encountered, so brass is not an option. Suggestions, please. Thanks.

02-05-2006, 08:41 AM
Use leaded bronze. Most types are stronger than mild steel and work harden to provide a non wearing bearing surface. It is corrosion resistant and reasonably easy to machine.

If you can find leaded manganese bronze it is about 50% stronger than mild steel.

Col Mckee
02-05-2006, 01:08 PM
Where can I find leaded bronze in 1 1/2" shaft size?

02-05-2006, 01:31 PM
Check with your usual metal supplier. I'm in Canada so any recommendation from here won't be of much help.

Oh, sorry but you can't have my piece. I may need it. http://bbs.homeshopmachinist.net//biggrin.gif


[This message has been edited by Evan (edited 02-05-2006).]

02-05-2006, 03:14 PM
Sure you dont mean nickel bronze? that stuff is tough.

Col Mckee
02-06-2006, 06:19 PM
Can I have half of it? Only kidding. Looks like what you have is cored. Do you know what alloy it is? My local metal suppliers don't know what leaded bronze is...kind of like me 'cept I'm not in the metal supply business. If I knew exactly what to ask for, I might get further. Thanks

cam m
02-06-2006, 06:32 PM
Col Mckee
If I were to set out to build a side entry drilling swivel, I'd give full consideration to chrome OD sleeves for a VEE packing to ride on. The wash pipe we normally run is chrome plated for wear resistance. Another option, would be a 1 1/2 hydraulic cylinder shaft with the chrome skin ground or peeled off between the seal areas. To drill a water well though, you shouldn't need a life of more than 30 or so hours unless you're going into business.
FWIW, if you're in oilpatch country, you could get a 1 1/2" polish rod and packing. Generally, they're only worn in the middle and are finish ground to a very good finish. The packings are quite robust as well.

02-06-2006, 06:37 PM
I believe that piece is free cutting phosphor bronze, UNS C54400. It has about 4% lead for easy machinability.

Col Mckee
02-06-2006, 06:51 PM
I knew this was going to get complicated! I'm not in drilling country so finding anything indigenous to the drilling endeavor would be a long distance proposition. The 1 1/2" hyd cylinder shaft may well be a viable alternative. Why grind off the chrome skin between seal bearing surfaces? What exactly is Vee packing? I was going to use Aluminium for the outside housing - any better suggestions? Thirty hours should bore the well plus ream it out several times for an 8" casing, but I'd like something left in case I ever got the urge to do it again. Thanks.

02-06-2006, 11:39 PM
You can buy rotating joints like this:

from McMaster-Carr. 1" size goes for $208. Look at page 93 of their catalog. http://www.mcmaster.com/


cam m
02-07-2006, 02:42 PM
Col McKee
1. Why grind off the Chrome skin between the seal areas? - because your design as described called for cross drilling between the upper and lower seal to allow the drilling fluid to enter from the side and go down the center of the pipe. The chrome is hard and wear resistant - precisely the properties that make drilling difficult.
2.Vee packing is a chevron profile packing made of fibrous material perfect for loose tolerance high pressure seals. Properly installed the vee packing self energizes - the higher the pressure, the more seal force. Basically an oversized lip seal. One of the advantages is that grease can be injected between the individual packing rings to further energize them.
3.If you can modify the design of the top drive so that the pipe is driven by a sprocket below the end of the pipe, you can use the swivel shown in the post above. The issue then becomes suspending the load.
4.How deep do you expect to have to drill? A large bore shallow well may lend itself to dry auger or cable tool drilling.

[This message has been edited by cam m (edited 02-07-2006).]

cam m
02-07-2006, 05:15 PM
Col McKee
Is this the class of rig you're building? http://www.deeprock.com/hydra%20drill%20main.htm
If so you should be able to use a common lip seal. An aluminum body for your swivel is fine. I doubt with a water well rig you'll be pumping more than 30 gal/min at more than 30 psi. A lip seal should do fine or a double o-ring with grease between. O&G drilling equipment I'm used to is far heavier and deals with far higher circulating pressures and rates than you'd ever need (2000 + psi at 500 gpm are not uncommon)

Col Mckee
02-07-2006, 07:46 PM
My drill rig is similar to the deep rock unit except trailer mounted and more of a fork lift raising and lowering design. I expect to use 1" shedule 80 or 40 for stem and a big pump for recirculating water: essentially what you have described. Thanks for input: I have located 1-1/2" chromed rod for no cost. Is rust not an issue? I can disassemble and oil when I'm done, but my cylinder shafts on exposed equipment do pit up when left to the elements. I kindof figured the chrome would have to be ground off where I was cross drilling, but didn't know if there was another reason. Again, thankyou for your input. John

cam m
02-08-2006, 10:45 AM
Col McKee
Frankly, corrosion and pitting inside your swivel is the least of the considerations. The seals and seal wear area are generally considered consumables because the drilling fluid is often loaded with abrasive solids from the formation you're drilling. Internal corrosion is relatively low priority for design.
I am curious what drill pipe connection you plan on using? Frankly, NPT will work, but if you have rough drilling or high torque your string can torque up in the hole and be difficult to break. The other issue is that the chromed shaft may be fiendishly tough and/or hard so single point threading in a lathe or splicing a Schedule 40/80 nipple on with a weld may be the easiest functional solution.
What do you intend to use for pipe lube on the connections? Water well drillers use non toxic stuff, O&G drillers use hydrocarbon based thread lube often laden with either powdered copper or lead similar to Never - sieze (sp?). Nasty stuff to put down your source of drinking water.

Col Mckee
02-08-2006, 09:05 PM
Im using a piece of 2" CRS Hex at the output end of the swivel. The "inside" end is drilled and tapped 1 1/4 12 to receive a male 1 1/4 straight thread on the 1 1/2 chrome shaft which is turned down accordingly. The outside end is tapped 1" x11 1/2 NPT to receive the first section of drill stem which'll be 1" pipe in 5 foot sticks. Hadn't thought much about pipe dope but figured I'd use a teflon based thread sealant suitable for potable water. Ground around here is mostly clay and I figured on going down as far as I could and then reaming hole out as large as I could to create as much storage as possible. I guess if breaking the joints loose becomes an issue, I'll have to back up and regroup. I've got two dug wells on this place: each about 30 feet deep and they've got 15 feet or so of water in them, but are too shallow and down hill from the feed lot. I 'm hoping to get down 100' or more before hitting too hard of rock. John

cam m
02-09-2006, 09:42 AM

If you run the pipe pin or male end up, you may drop it down the hole if it slips through whatever you're holding it with as you run it or pull it from the well. Fishing pipe out of the wells can be tricky and time consuming - whole careers have been made out of fishing around the oil patch. I would suggest running your pipe such that you have a coupling left on top all the time and using a forked plate. Simply slip the plate under the coupling and set down on it. You can then rest the backup wrench on the plate and back it up against your mast or rig and twist on the top. To do that with your swivel, just run a sacrificial nipple under your swivel and put your wrench on that. If you use steel pipe wrenches at least 18" of a reputable brand, you can safely use cheaters up to 4" long alone to break your drill string. Torque shouldn't be too big an issue, just inconvenient.

[This message has been edited by cam m (edited 02-09-2006).]

Col Mckee
02-09-2006, 08:21 PM
Thankyou for the pointers. I hadn't thought far enough ahead to worry about dropping drill stem during the retrieval process. I've done a lot of horizontal boring over the years where losing pipe (usually from breakage or inexperienced help running the big 3/4" Milwaukee in reverse and unscrewing sections) is aggravating but never too difficult to retrieve. Think I'll use either a sacrificial nipple or maybe turn the 2" hex down and thread the OD 1" NPT for a line coupling. Once the rig is operational, I will drill a 20' deep experimental bore about 4" diameter as a test run. Am hoping to install a sleeve for my telescoping martin house with a pneumatic assist, as raising and lowering said martin house gets more difficult each spring. Thanks again. John

02-11-2006, 08:41 AM
You can get most bronze alloys in solid from National Bronze , Houston. 800-231-0771. I have no connection to them but have bough from them before.

As to other materials, if you gave a length I missed it, but: you can get 1045 psq(pump shaft quality) at 1.5 od tols are +.000 -.001 on od and very straight( I think .015 tir in 3 ft) or you can use chome plated cylinder rod. It is usually 1045 also but make sure you get CPO (chrome plate only) not the IHCP (induction hardened chrome plated) stuff as the IHCP is 50-55 rc to .06-.100 deep on the OD and very hard to work. Both of these come in 20-24' long lengths and are shipped in paper tubes.