- How long do the wheels last?
- It depends on the down-hole conditions, the severity of the dog legs or deviations, the interior condition of the tubing, etc. As a rule of thumb, the wheels should be checked approximately 3 to 4 times longer than the prior history of failure. For example, if the well was going down once a month, it should be checked in 3 or 4 months to determine the wheel life.
- How many do you run and where?
- We recommend you run them on the first 3 or 4 sucker rods right above the pump and in areas where there is known deviation. We also recommend Wheeled Rod Guide® couplings where you have had repeated rod parts or tubing leaks. Don’t hesitate to cover the high wear area completely; it is reasonable preventive maintenance.
- How about down-hole temperatures?
- We use different materials for different temperature ranges. The S/UHMW polyethylene wheel is good for temperatures up to 175 F. Amodel material is used for temperatures up to 350 F.
- Will Wheeled Rod Guide® couplings work in a well with corrosive conditions?
- Yes, our guides are electroless nickel-plated, but for highly corrosive conditions we recommend our stress-proof rod guides.
- Will they run in paraffin?
- Yes, the S/UHMW polyethylene wheel has a very low friction coefficient and paraffin generally will not prevent the wheel from rolling.
- What if a wheel locks up?
- In the unlikely event that the wheel does lock up, the result will be a softer, more flexible material rubbing on the tubing wall, and a flat side will wear on the wheel. This result will also spare the tubing wall from wear. You will have prevented steel rubbing against steel.
- Can you use a rod rotator with the Wheeled Rod Guide® couplings?
- Yes, a rod rotator will create even wear on the wheels.
- Can the wheel break or fall out of the body?
- In the highly unlikely event of a wheel breaking, it would flush to the surface with the fluid. The standard wheel has specific gravity of .94.
A wheel cannot fall out of the slot even if a pin shears because there isn’t enough clearance between the rod guide body and the tubing wall.