1. What products does BICO Drilling Tools, Inc. offer?
BICO Drilling Tools, Inc. is a recognized leader in the design, manufacture and service of downhole drilling motors, PBL (multiple activating circulating sub), rotary steerable tools, drilling jars, shock subs that are used in the oilfield industry.
2. What types of Motors does BICO offer?
BICO offers both conventional and performance motors.
Flexdrill incorporates conventional power section and available in variety of configurations ranging from 1-11/16 to 11-1/4 sizes and suitable for use in coiltubing to deepwater applications.
FlexStar incorporates conventional power section with premium hard rubber components and innovative lobe design that utilizes “teeth” on a contoured surface to provide tighter seals, and enhanced performance.
SpiroStar incorporates Evenwall™ performancepower section with unique uniform rubber thickness that provides unparalleled strength and able to withstand harsh environments.
3. What is Hysteresis?
As rotor lobes impact stator lobes repeatedly, heat accumulates in the center of an elastomer stator lobe due to friction between rubber molecules. This can cause the center of the stator lobe to melt, weaken, melt or eventually tear away, the classic stator “chunk”.
4. What type of bearing assemblies does BICO offers?
BICO provides two type of bearing assemblies G1 and G2. These are mud-lubricated lower end that utilize stacked ball-and-race to handle thrust loads, while radial bearings handle side loads. An advantage of mud lubricated bearings is that there are no limitations on bit pressure drop compared to sealed bearing assembly and they are more versatile in high mud weights. The bit pressure drop can be maximized for optimum penetration rate, without adversely affecting the life of the bearing assembly.
The G1 conventional mud-lubricated bearing assembly is a field-proven design that has been deployed in most drilling applications. The G1 is ideally suited to be run with Flex DrillTM power sections.
The G2 (second-generation) performance bearing assembly is designed for today’s harsher drilling environments. With improved radial and axial bearing design, the G2 assembly can deliver the higher torque of either “HR” or SpiroStarTM power sections. Its improved radial bearings provide increased durability in high dogleg applications. A short bit-to-bend G2 bearing assembly is available in limited sizes. Contact your BICO representative for availability.
The G3 (third-generation) performance bearing assembly is in the development stage.
5. What is Rotor Catch Device?
Rotor catching device is a safety feature designed to secure lower parts of the motor in cases of connection failures, twistoff or backoff. All BICO motors are equipped with a rotor catching device to minimize the risk of the fishing.
6. What is Driveshaft Retention System?
Driveshaft retention system is an additional safety feature that BICO offers in order to retain the drive shaft in the event of connection failure or breakage of the driveshaft or transmission assembly.
7. What is Aniline Point?
Aniline point is the temperature at which specific volume of aniline dissolves in a similar volume of drilling fluid. Relatively, aniline point of fluids has typically been used as an indicator of the tendency of circulating fluid to degrade the elastomer components, thus changing physical properties of elastomer (e.g. softening and swelling). Therefore, ideally oil-based mud should have the highest aniline point temperatures and higher than downhole operating temperatures in order to minimize the risk of elastomer degradation.
8. What is maximum allowed Sand Content (Abrasive Particles) and Solids allowed?
Solids (e.g. bentonite, polymers, drill solids) suspended in a water-based drilling fluid can cause internal erosion and abrasive wear to the drilling motor components, particularly the stator, rotor, transmission and bearings. BICO recommends that the solid content be kept below 5% and that the sand content be held below 1%. Proper use of the rig’s mud cleaning equipment can achieve these levels and help ensure longer motor life.
9. What are the Effects of Chlorides on Power Sections?
Drilling fluids that contain chlorides can reduce the life of the power section due to corrosion particularly at high temperatures. Therefore, if the drilling fluid has chloride content greater than 30,000 ppm, BICO recommends running a carbide coated rotor. Damage can begin to occur at lower chloride levels if the temperatures are elevated.
10. What is the Shelf Life of the Stator?
Discussion with power section suppliers for both types of power sections will reveal that the industry-wide limit (conservative) for stator shelf/storage-life is approximately two years from the date of manufacture and/or reline. Exposure to certain gases and environmental conditions can decrease the storage life of the stator elastomer, but again, two years (24 months) is a conservative limit.
The following factors contribute to the degradation of stator elastomer mechanical-properties, fatigue resistance and/or stator shelf-life:
- Exposure to oxygen (O2) in the atmosphere (air)
- Extreme cold or heat.
- Exposure of the stator elastomer to ultraviolet light (a component of sunlight).
- Thermal cycling from hot to cold
- Exposure to ozone (O4) from industrial or natural sources.
The following practices are recommended to extend stator shelf/storage-life:
- Store stators inside away from sunlight and where temperature extremes are also mitigated.
- End caps (air-tight) made of rubber/plastic or plugs of closed-cell foam (again airtight) should be fitted on each end of the stator. End caps can be taped to the OD of the stator tube to ensure they stay on. Plugs of closed cell foam should fit under compression to the ID of the stator tube to stay in place. However, these plugs should not be so oversized that they leave passages for air to pass into the stator when they are put in place.
Rotors generally are not considered in the estimate of power section storage life, as they do not have an elastomeric component. Also, their coatings do not readily degrade on the shelf unless they are exposed to corrosive chemicals or they are made from carbon steel versus a corrosion-resistant stainless steel. Storing a rotor inside a stator for long periods, however, can cause a permanent deformation of the stator’s profile due to the weight of the rotor.