What are your average drilling speeds?

Discussion in 'Geothermal Loops' started by Calladrilling, Jan 6, 2012.

  1. Calladrilling

    Calladrilling Member Industry Professional Forum Leader

    What are the average times it is taking you drillers to do a complete bore?

    From rig set up to rig knock down.
    Type of rig,mud pump,drill bit size and type?
  2. waterpirate

    waterpirate Well-Known Member Industry Professional Forum Leader

    Dewayne Dean and I are the only regulars that frequent here and drill. He runs a sonic rig and we do mud rotary.

    From the time the rig gets onsite to bit pennetration is about 20 minutes. From that moment forward we move the rig to the next hole every 30 to 45 minutes. That time includes drilling 200 feet, setting the loop, and grouting with standard 20% grout. We use 10 foot rods, so if you are counting we do 40 rod changes in that time, including everything else. We run a 3 man crew. Driller, and 2 helpers.

    The rigs we use are so heavily modified to the point that I would call them shop built.

    The number one thing I see that detracts from geo drilling is the drillers understanding of what we do, i.e. mud rotary. A full and complete understanding of the mud is critical. I never drill with spud mud, I never drill with a mud weight greater than 10# per gallon.

    The other thing that is critical is getting a Henry Ford mindset. Streamline everything, look for ways to do things better, everyday. Standardise the procedures you use from set up and mobilisation to the actual drilling proccess. When we drill it goes so fast that if one team member is out of position it costs time and money. Everyone on our team has had intensive training/brainwashing by me to ensure they know where they are supposed to be and when.

    If team members are moving around like electrons bouncing off of one another nothing will work well. I remember well being drilled as a youth, if you rush the ball and are out of position, the other team will make sure the ball goes to where you are not.

  3. Calladrilling

    Calladrilling Member Industry Professional Forum Leader

    45 mins!!!

    I am surprised no other drillers are on this forum. I may have found it late, but I love it here and find myself searching and reading post for hours at night LOL.
    30-45 mins to set up and drill,loop,grout and breakdown rig is unbelievably fast!!!
    We run a canterra ct311 with a 5x6 mud pump, drill a 6" bore with a drag bit.
    I just can't imagine have a 200' bore done in 30-45 mins. I would love to watch your team drill a bore to find some pointers for fast production.

    Do you mainly use 3/4" loops too?
  4. Palace GeoThermal

    Palace GeoThermal Well-Known Member Industry Professional Forum Leader

    Eric and I drill in very different conditions.

    Here in Utah some days we can do 3 - 200' loops other days we are lucky to get 1 - 200' loop in.
  5. Calladrilling

    Calladrilling Member Industry Professional Forum Leader

    I imagine your running a air rig?
    We are not too far from Eric in Delaware. We are in Southern part of New Jersey and run mud rotary. We drill mainly in sand and clay. We do ocassionally hit hard formations but it's very uncommon.
    I am very amazed with the possibility of drilling 10 bores in a day though.
  6. Palace GeoThermal

    Palace GeoThermal Well-Known Member Industry Professional Forum Leader

  7. waterpirate

    waterpirate Well-Known Member Industry Professional Forum Leader

    Our standard fair is 3/4 x 200 for residential. I will drill what ever it says on the contract. If we are doing 1 x 300 the benchmark is 7 holes per day, we frequently get more. if you can not get 7 x 300 in a 10 hour shift, you get your walking papers.

    I would be happy to talk to you about the theory of drilling, and generalities, but I am reluctant to" give you the keys to the candy store".

    Moving men and equiptment at that speed takes a lot of mental focus and it is not easy. The other part of the equation is that you can not take a chrysler K car to the race track and expect to finish in the top ten.
  8. Calladrilling

    Calladrilling Member Industry Professional Forum Leader

    We run an older water well based drilling rig. I am slowly transforming it to more geothermal friendly to gain more productivity. We can do 1-2 bores per day and that about it.
    I know we are wasting a lot of the drilling.
    We need to upgrade to a better grouter too ( geo-loop 50-500 is our next grouter) but it just seems out of reach for us to do anymore than 3 bores per day no matter what. 7 300' bores blows my mind!

    Are you drilling with a full sized rig or a compact?
    What size bore hole?
  9. Bergy

    Bergy Member Industry Professional Forum Leader

    I thought a 4" bore was standard for Geothermal loops using 3/4" pipe.

  10. Calladrilling

    Calladrilling Member Industry Professional Forum Leader

    Bore size is also related to drilling pipe sizing too.
    We run 4" OD drill rods. So obviously we can not drill a 4" bore. That leaves us drilling a 6" bore.
  11. Palace GeoThermal

    Palace GeoThermal Well-Known Member Industry Professional Forum Leader

    we drill 4.75" hole
  12. waterpirate

    waterpirate Well-Known Member Industry Professional Forum Leader

    We drill the smallest hole that the loop will fit in. For 3/4 loops in sand I have used a 3.5 bit. Cutting more hole than you need costs you money in labor and grout needed to seal the bore. A geo hole only has to accept the loop and the grout. There is reallyno need to pay attention to anything in the bore except for reaching TD the fastest.

    My road rig is mounted on a FL80 with a Martinson military front drive axle. Our other rigs are on excavator tracks and a commercial log skidder. The road rig has a 5x6, deck mounted grouter that mixes 75gallons a batch, 100/100 air, is top head drive, we run mayhew jr rods box up. In my opinion the best grouter on the market is the one you build to use the rigs mud pump.

    When we looked at buying a rig to do loops with we could not buy what we wanted, everything had a comprimise factor so we built.

    We use a mud pan and typically do not shovel. The rig is equiped with a mud cleaning system I designed and built on the rig. The mud cleaning system was a result of the helpers could not shovel the pan at the speed the rig drills. A side benifit is that I average1,000 holes between rebuilds on the 5x6. About 1 yearsworth of production.

  13. Calladrilling

    Calladrilling Member Industry Professional Forum Leader

    I would really like to see your rig in action.
    I get your concept of not having to worry about anything but shoving a loop, grouting it in record speeds.
    I was taught drilling water wells in our family business. We are getting more and more geothermal drilling jobs and slowly converting our rig over for more loop production.
  14. Calladrilling

    Calladrilling Member Industry Professional Forum Leader

    Hey Eric,
    Any you tube videos of your rig in action?
    I would like to see your mud system and drilling rig in action.
    What size drill rod you have to drill a 3.5" hole?
  15. waterpirate

    waterpirate Well-Known Member Industry Professional Forum Leader

    No video

    No demo

    See keys to the candy store

    mayhew jr. box up

  16. Rig 40

    Rig 40 New Member

    I find myself asking the same questions. We are currently a large water well drilling company that does both domestic and municipal water wells that is looking into doing more geo work. With that said, we are equipped to do mud drilling on much larger scales than required for geo. Biggest question on our end is mud recovery. We are used to running a 4000 gallon mud recovery tank. From what I have seen on you tube I am unable to determine how most contractors are mixing and recycling their mud. We have a small apartment complex (read 50 holes) that we are going to attempt, drilling 5.75 in holes at 200 ft and were wanting to pick the brains of the more experienced contractors. These holes will be in saturated silt with small amounts of clay that will not stay open with out mud. This is not the norm for us to drill in this type formation. typically we drill in sands and gravels of the same unconsolidated but dry. For what it is worth we run speedstar 30k rigs. Thanks for any insight in advance.
  17. waterpirate

    waterpirate Well-Known Member Industry Professional Forum Leader

    Welcome rig40,

    The only way to drill production geo with mud is to use a pan. It is also referred to as a portable mud pit. The design and application of a portable mud pit is a science unto itself, there is no one right answer.

    When I do production work since keeping the mud weight low is the key to fast penetration, I like to turn over the mud quickly to help with cleaning. For me the ideal pan has just slightly more capacity than the bore hole at TD. So for me drilling 200' bores at 3.5 to 4 inch diameter my pan holds around 110 gallons give or take. Running the 5x6 turns that mud over pretty quick. The shape is also crucial to ensure good flow. My suction is tottally encapsulated inside a 3/8 mesh to prevent clay or stones from entering. The pick up for the cleaning system is in the same mesh in front of the suction for the 5x6 and the return from the system drops clean fluid directly into the suction.

    The pan can be full of all kind of crap yet the circ system is being fed clean mud down hole.

    For the saturated silts and clay you described I would want a polymer such as unidrill in conjunction with a wetting agent like drill x to prevent the clay from swelling and booting up. I would also use a chevron drag bit, as I want to cut the clay, encapsulate it, and spit it up the hole. I have seen a lot of guys use scratcher bits in clay that really only disolve it and ruin your mud. The scratcher is good for shale IMHO but not clay.

    Mud is a pasion of mine and if I had to guess you guys allready have what you need in house, it just needs to be scaled back, speeded up, and converted to production drilling.

    Hope this helps.
  18. Rig 40

    Rig 40 New Member

    We do currently run polymer (baroid easy mud) . Our catch pan as you say is just a livestock water tank that we pump to our mud tank that is equipped with shaker and desanders. In your type operation you don't reuse you mud from hole to hole or are you drilling with your grout then adding sand later? We drilled the test holes with standard button bit tri cones and got excellent penetration rate. Not familiar with the cheveron type bit you mentioned. By excellent I mean that the hole was completed in approx 2.5 hrs. If you are reusing you mud how are you moving it? Keep in mind that we are drilling 6 in hole and setting 1 in loops. Thanks for your input. I have found this forum extremely useful and hope to continue.
  19. Calladrilling

    Calladrilling Member Industry Professional Forum Leader

    We drill 6" bores too since we have 4"OD drill rod. We have a portable mud pan too.
    We drill mainly in sand,and clay with a 3wing drag bit. The penetration rate is pretty quick too.
    We do not have a shaker, or use our desander ( thins our mud out to fast). We have a 3 chamber mud pan to settle sand out in stages. Our mud pick up line in the back corner of our pan inside a screen cage to stop any objects from being picked up and clogging the 5x6 pump.
    We generally only do 1 300' or 2 200' bore per day and that's looped and grouted in place with either 20% solids or thermal enhanced grout ( which ever is in the contracts).
    We are are mainly a water well drilling company too and I have been converting our rig over for geothermal production to speed up. We have built a truck mounted loop reel, a loop insertion rod, and working to go with smaller diameter drill rod sooner or later to be able to drill a smaller bore and save on grout and speed up drilling more.

    I've learned the trade from my father and it's hard to break him from his old ways. His concept is slow and steady, while I wish I could drill fast enough to lift the rig off the jack stands. LOL.
  20. waterpirate

    waterpirate Well-Known Member Industry Professional Forum Leader

    We do not reuse our mud per say. Water for drilling has always been the issue, never seems to be enough. Our shaker and cone comes off our pit, so no seperate tanks. When we reach TD we set the loop through the pan, the loop displaces the bore mud into the pan. " Ryan cover your ears now";), then we pump that fluid into the grout hopper and mix grout. The grout displaces another pan of mud for mixing a second batch of grout, we discard the last batch of mud out of the pan. We then pick the pan up off the hole and the loop and move to the next hole.


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