FAQ

Frequently Asked Questions

 The motor selected for your job is based on the drilling unit you are running and the amount of fluid your mud pump (GPM) will deliver. Visit our Recommendations page for more information on what motor works best for you. Or Contact our sales team for more help deciding.

 The drill bit size is selected by the customary size for the largest OD of your drilling string, including the drilling motor. Since the drilling motor is probably has the largest OD, then this will be the size Adtech will use in recommending a drill bit size.
 Our Recommendations page will give you the sizes that normally run with Adtech motors. The type of drill bit is decided by the formation you will be drilling in. Read about what bits are preferred in specific applications in our Drill Bits 101 guide.

 The amount of GPM for is decided on by the motor size. By looking at the charts provided you can decide what amount of fluid you will need. There is range for each size that can be run, which we call running on the "low side" of that range or the "high side" of that range. The larger the motor the more distance in between low side and high side. Optimum range would be the ideal GPM for that motor.
 For instance a 3 12" 6-7 Lobe Drilling Motor range would be 60 to 70 GPM. 60 GMP would be the low side, 70 GPM would be the High Side & optimum would be in the middle.

 The differential PSI is the pressure measured when you apply torque to the drilling motor. When you start the drilling motor and you run the needed GPM's, the restriction in the motor will generate a PSI. This is the normal off-bottom PSI recommended for each motor. Once you touch bottom with the motor and start to drill, your pressure will rise which is known as on-bottom PSI. This is the differential pressure reading. A rule of thumb is that this is a 200 PSI increase over the regular pressure reading. If you stall the motor out, the motor will not turn when on bottom due to not enough pump or too much weight on the bit causing the differential pressure to spike. This is the time to turn off your pump, pick up off bottom and kick the pump back in and see if your pressures go back to normal operating readings.
Check our Recommendations for accurate PSI readings.

 The size of sonde housing to be used is determined by the size of motor you will be using. The sizes match up to each motor size. If you are using a 3" motor, your sonde housing will be 3 to 3 12" OD. If you are using a 4 34" - 5" motor, the housing will be 4 34" to 5" OD. Most housings will accept either size of sonde housing: 15" or 19". The sonde housings are designed with a 4" spacer to be added if you are using the 15" and the 4" spacer left out if you are using a 19". Some Ditch Witch Sondes have larger OD's then the normal and will not fit the space for the sonde.

 Crossovers are used in any connection area where two connections don't match up. This should be discussed with the Adtech Sales Team in full to make sure you get the right hookup for your application. It's a good idea to draw out a diagram of your lower string to find out the necessary crossover subs needed. Adtech designs their motors to attach to the most common sonde housings. The sonde housings usually have a box at the drill pipe end and will connect to your drill pipe. For example, if the sonde has a 2 78" Regular Box on its connection and your drill pipe has a 2 78" Firestick Pin connection, you would need a crossover of 2 78" Regular Pin by 2 78" Firestick Box.

 The bit is attached to the end of the motor closest to where the bend and serial number is located on the motor. The end of the motor is called the bit box and will have a space between the housings.

 All Adtech motors are machined to a 2° bend with a stamp on the motor. Special motors can be ordered with smaller or larger bends, but the 2° is the degree requested for Horizontal Directional Drilling.

 To decide what top sub you need will depend on what you are going to attach it to. If it is going to a sonde housing, you will have a box end on your sonde so the motor should have a pin end with the same connection as your sub. If it is going to a monel drill collar, then a crossover sub might be used and this might be one you have in stock. The top sub should match those connections. Adtech can change top subs on most motors to satisfy the need of most drill string. This should be discussed with Adtech Sales. Adtech can provide crossovers as we manufacture them on site.

 While operating a drilling motor, your drill pipe should be rotated slowly. This is about 20 to 25 RPM for any size of motor. You are only rotating to stop the correcting you have been making with just the motor. If you rotate any faster, you will have to undo wear on the housings of the motor, especially the bent housing area.

 Setting up the motor to make a correction: Attach your steering device to the drilling motor on the surface (Sonde or Steering tool). The sonde should have the clocking device set to 12:00 o'clock and the bend of the motor (stamped serial number) facing upward.

 Now, go to bottom and assuming you want to correct right away, turn the drill string to the necessary clocking reading. For example, if you want to drill to the right. Turn the drill string until your readout says 3:00.

 Start up your pump, but don't rotate the string and then drill in that direction with just the motor turning the drill bit. If your readout is not the direction you want to go, pick up off bottom, and turn the drill pipe to the corrected figure then continue drilling in that direction with just the motor without rotating the drill string.

 When you have made your corrections and you wish to just drill straight in that direction, start rotating the drill string slowly. The eccentricity caused by the bend in the drilling motor will not be noticed and not cause any problems.

 A High flow sonde housing is needed with a downhole drilling motor. The Low flow sonde housing will not work. Adtech has all sizes of sonde housings for rent and sale, 2 12” to 8” OD.

 HDD Adtech Motors typically require repair every 100 to 150 hours. If you've had a rough bore or see fluid coming out around the indent by the drill bit then it would be wise to send it in. You might want to send it in earlier if you have a long bore coming up and want the motor in top shape for that job.

 Most sonde housings can be repaired a few times. Adtech can test the sonde housing for leaks and recut the end. If the water pressure going through the holes washes out into the transmitting slits, then the sonde would not be repairable. We can usually remove the end plug and put in new modified ones if necessary. Adtech will service your sonde housing and do repairs at no cost (unless you would need additional parts: new plug or new ends attached).

 After running your motor, run clear water through it, if possible, preferably with your pump. Some times you can put some mineral oil in the top end after cleaning out (if you are going to be down for awhile) and rotate it down through the rotor and stator. Clean off your top/bottom threads, coat with thread coating and put back on the protective ends supplied with your motor. If those are not available, clean and coat threads, wrap with some cloth (rag) and apply duct tape to protect. The inside of the bearing pack is completely sealed and should not be serviced. If you think there is a problem in this area, then you should send it in to be checked out.

 There is no kit available for you to repair your motor. The joints of the motor are all treated with locking compound and Adtech has special breakout machines to undo the connection of the drill motor. The above servicing is about all that Adtech would recommend that you try to do in the field.

 At this time, Adtech doesn't actively pursue the Oilfield Downhole Motor business. However, we do get several inquires a week and we do explore every avenue to provide the necessary equipment needed. Adtech primarily caters to the Horizontal Directional Drilling Industry. Though we take every call into consideration, if we can provide the motors for a particular job, depending on the application needed, we'll do so. Contact Adtech Sales Team and see if we can get you what you're looking for!

 Adtech employs multiple methods to deliver our tools to our customers in a timely manner. We use our own drivers to speed out motors to customers within one to two days, all over the country. If our drivers are all out on jobs, we hire out hotshots to get the motors on site within three days.

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