Monthly Archives: August 2014
Developments of linear motion shale shaker
A more recent development, introduced in the 1980s, is the linear motion shaker. Developments inin screen technology have made it possible for pretensioned screens to be layered for obtaining very precise cuts while still maintaining an economical screen life.\
Linear motion is the best conveying motion to move convey cuttings” uphill”. Screens can be elevated to retain the cuttings longer to obtain a dryer-reduced liquid content discharge. Also, finer screens, with smaller openings, can be used on the linear motion shaker. One application of linear shakers is to to screen the underflow from desanders and desilters rather than using a mud cleaner. This device is called a “mud conditioner.”
Present technology includes liquid salvage-devatering or solids flocculation-that strips the liquid phase from solids and returns an almost clear stream of water into the mud returns an almost clear stream of water into the mud system. This process includes a decanting centrifuge with pre mixed polymers injected into the feed line of the centrifuge causing flocculation. The solids are coalesced inside the centrifuge resulting in separation of solids from the liquid, and the solids are then discarded.
A recent innovation for environmental purposes and more liquid retention, is the dryer. The discharge from linear shakers, desanders and desilters is flowed across another linear shaker with even finer screens( down to 450 mesh, or 32 microns) and usually a larger screening surface. Any liquid that escapes can be retained in the sump. The sump pump returns the liquid to the active system, usually to the centrifuge feed tank.
These systems, or combinations of the various items discussed above, meet most environmental requirements and conserve expensive liquid phases. Discharges, leaving a damp, semi-dry solid mass to remove for disposal.
Petroleum Engineers See Highest Increase in Median Average Salary
Petroleum engineers experienced the highest increase in median annual salary since 2011, according to a recent report from the American Geosciences Institute (AGI).
In 2013, the median average salary for petroleum engineers was $132,000, and had increased by more than $10,000 since 2011, according to the Aug. 12 report, which quoted data from the U.S. Bureau of Labor Statistics.
Since 2011, all geoscience occupations – with the exception of atmospheric and space scientists, geographers, environmental science and protection technicians, engineering post secondary teachers, and atmospheric, earth, marine and space sciences post-secondary teachers – recorded increases in their median annual salaries, while decreases ranged only from $10 to $2,760 per year.
The average median annual salary for geosciences-related occupations last year was $83,311. With the exception of soil and plant scientists and technician occupations, the median salaries for the geoscience occupations are higher than the median salaries for the broader occupation groups.
“The geosciences continue to be a lucrative employment option within the current workforce,” AGI said in the report.
Petroleum engineers are in demand in the United States thanks to the surge in exploration and production at home and worldwide. These workers are in demand not only in the private sector, but at the United States’ Bureau of Land Management, to oversee mineral resources are millions of acres in the nation.
ABC News reported Aug. 18 that the petroleum engineer job ranked among the best-paying jobs of 2014. Petroleum engineers also have the highest starting salary of any of the engineering degrees offered, with an average starting pay of $89,000 and a mid-career salary of $159,900, according to USAToday.
DCLW Decanter centrifuge arrived to Russia
Today I got a good news from my Russian client, and our four sets frequency conversion decanter centrifuge had already smoothy arrived to destination – Russian. At the same time, my client also took some pictures for me.
The four sets decanter centrifuges respectively used in four set ZJ3000 drilling rig. Decanter centrifuge to be as the fourth stage solid control equipment which is the obbligato to drill deep well. Drilling mud will get the better treating effect by decanter centrifuge. So it is widely used in any drilling field.
The main structure of the frequency conversion centrifuge is the drum, main motor, back motor and frequency conversion control box. The material of the drum is full stainless steel forging with the better abrasive resistance and corrosion resistance that determines the long service life.
Otherwise, frequency conversion centrifuge is more flexible than the fixed frequency centrifuge. Because it has the unique frequency conversion control box to control the centrifuge ration speed that directly control the treating capacity and treating effect.
Now DCLW series decanter centrifuges are widely used all over the word and obtain the highly praise which used in different industries, such as, petroleum drilling, waste management, HDD, CBM, geothermal environmental waste and etc. We also can design and manufacture it according to customers different requirements, if you have any demand of it please send email to us, believe we will provide you the satisfactory service.
Mud tank agitators main structure
DCJBQ mud agitators include an explosion-proof, “C” faced motor, reduction gearbox (helical-bevel for horizontal agitators or all helical for vertical units), impeller, and shaft with assembly bushings. Motors range from 5 to 30 HP and may be supplied in several power configurations.
Design features:
Design features that minimize maintenance and maximize reliable include; Gearboxes house either a double or triple reduction helical bevel gearing set that is so precisely ground that there is a minimal amount of back lash in the gear sets, eliminating a ” slamming” effect of the gears at start up, promoting a longer life. Each helical bevel gear set is 98% efficient. Therefore, a double reduction gearbox is 96% efficient and a triple reduction gearbox 94% efficient. A typical worm gear set is only 85% efficient and loses most of its efficiency through the generation of heat.
Explosion proof Motors:
Explosion proof motors are designed to withstand pressure washing and exposure to corrosive fluids with no contamination. DC uses face motors that bolt directly to the gearbox housing eliminating any alignment issues.
Impellers:
Axial and radial flow patterns created by the impellers provide optimal suspension and mixing. DC offers a 60, 45, or hydrifoil style impeller, available in carbon steel and 310 series stainless.
Working process of mud cleaner
Sand trap is a tank that usually sits underneath the shale shakers. Flow from the shale shakers goes into the sand trap. The purpose of the sand trap is to give temporary protection to the rest of the system if a shale shaker screen splits. In this case, the larger solids will settle in the sand trap, and they can be later dumped through a large butterfly valve on the bottom of the sand trap.
A hydrocyclon is a simple but ingenious bit of kit no moving parts. It is comprised of a cone with a small hole at the bottom end. At the top of the cone is an inlet pipe, positioned so that mud entering the cone does so in such a way that is swirls around the inside diameter. An outlet pipe exits upwards, but the bottom end of this pipe sticks into the top of the cone.
As mud moves round the inside of the cone op, it eventually comes back to the inlet pipe position, where more mud is coming in. This forces the mud stream downwards, into the cone. As the cone gets narrower, the fluid speed has to increase to a ccommodate the flow rate. Very high centrifugal force are exerted on the fluid stream, so the heavier solids particles will move towards the outside of the fluid stream.
As the fluid stream nears the bottom, pressure builds up to the point where the fluid changes direction and starts back upwards, spiraling up inside the descending mud, which stays close to the cone inside surface. The solids particles, being heavier, cannot change direction so readily and are ejected at the bottom of the cone. The cleaned mud stream exits at the top of the cone, out of the overflow opening.
Large cones process larger volumes of mud and remove larger particles. Smaller cones process smaller volumes but can remove finer particles. Most rigs will have a set of 3 or 4 large cones, around 12″ diameter at the top. These are called desanders because they remove particles of sand grain size. Most rigs will also have a set of perhaps 16 or 20 small cones, 4″ diameter at the top. These are called desilters because they remove particles of silt grain size.
Design features of LW decanter centrifuge
LW series decanter centrifuge is a horizontal centrifuge with continuous feeding and continuous discharging. The settling speed is determined by particle size, particle shape, difference in density between solids and liquids as well as their viscosity.
Design Feature
Main parts such as the bowl and conveyor are made of corrosion-resistant stainless steel or duplex steel, offering high maximum bowl speed and high centrifugal force.
Dual motor drive makes bowl speed and conveyor speed adjustable.Screw conveyor flights tiled or lined with ceramic, tungsten carbide, or other hard alloys.
Optional planetary gearbox and hydraulic gearbox, offering wide range of differential speed adjustment . Multiple safety protection: bowl speed and differential speed detection, over-vibration protection, motor overload and overheat protection, bearing temperature monitoring, conveyor torque protection and gas-tight explosion-proof protection.
The main features of the decanter centrifuge are:
User friendly advanced control technologys
Sealed and pressure-tight construction
Two and three phase versions
Compliant with environmental noise regulations
Low operating costs, low maintenance costs
Low cake moisture – high solids removal – high centrate clarity
Compact – small ‘footprint’
Materials of construction to suit the rigours of the application
State of the art abrasion resistant materials
You are welcome to contact Tangshan Dachuan Machinery to get more detailed infos, we will supply our best service for you.
How to Best Maintain Drilling Fluid Centrifuge During Use
In drilling operation, drilling fluid centrifuge is one of the core equipment that is often used, it is mainly used for separating fine solid particles whose diameters are 2-7 μm from the drilling fluid, the use of drilling fluid centrifuge can effectively protect the drill bit, and also has a very important role in improving drilling speed. With the oil drilling industry technology is getting mature, drilling fluid centrifuge manufacturing technology has been greatly improved. However, some inherent mechanical problems are still not solved and continue to haunt users.
So, what are these problems?
Mainly for the below:
1. Bowl fault.
2. Wearing parts (inlet pipe, shockproof strip) problem.
3. Excessive vibration.
4. Outlet blocking.
5. Explosion-proof plug damage.
6. Centrifuge scroll wear.
7. Bearings failure in the process of using.
8. Drilling fluid centrifuge hose damage.
So how should we maintain the drilling fluid centrifuge during using?
The first point: the use of staff must be regular maintenance on the centrifuge, regular cleaning the inlet and outlet, add grease to the bearing parts;
The second point: regular inspect easy damaged parts on the drilling fluid centrifuge, like hoses. In order to ensure the process in the use of these parts is not a problem which influences the production. Finally, electronic products and TV sets, reduce the on-off times, when drilling fluid centrifuge started, preferably every 8 hours rather than an hour on drilling fluid centrifuge to start. Do all of the above, then you’ll find out centrifuge failure rate will be greatly reduced in use.
Drilling Fluid Management During Horizontal Directional Drilling
Horizontal Directional Drilling (HDD) is a trenchless construction solution to traditional open-cut methods used for utility conduit installation. Over the past four decades, advancements in HDD have made it an effective and common installation method, particularly in congested urban areas and environmentally sensitive areas, such as beneath rivers and wetlands, as it minimally impacts surroundings. The HDD process includes pilot boring, reaming, and product pullback.
Drilling fluid is used in all the three stages of HDD, functioning to: provide stability to the borehole, especially in collapsible soil and porous medium; decrease the frictional drag between the pipe and the borehole; cool the drill bit during excavation, and transport drill cuttings to the ground surface. Drilling fluid generally comprises an admixture of water and bentonite, and different types of additive can also be used to improve the fluid’s capacity to carry the cutting soils out of the borehole. Figure 1 shows the first stage of HDD in which the borehole is excavated with a mechanical cutting structure and the cutting soils are transported to the ground surface by means of hydraulic transmission (circulation of drilling fluid).
The drilling fluid pressure in the borehole must be high enough to provide borehole stability and adequate circulating pressure for cutting transport out of the borehole. However, excessively high drilling fluid pressure can also cause hydraulic fracture and release of drilling fluid to the ground surface, which is a critical issue encountered during HDD. This phenomenon occurs when drilling fluid pressure exceeds the shear strength of the surrounding soil, which causes cracks to propagate to the ground surface. Penetration of the drilling fluid into the cracks leads to operational (loss of drilling fluid, collapse of the borehole, bit balling, and circulating pressure loss) and negative environmental impacts. Figure 2 illustrates the growth of the crack around the borehole during pilot boring. Hydraulic fracture is the greatest concern in the first stage of the boring process, as it has lower annulus areas compared to the reaming stage. Therefore, higher interaction between drilling fluid particles in lower annulus areas causes an increase in annular pressure.
DRILLING FLUID MANAGEMENT
Drilling fluid management is a technique employed during HDD to maintain a proper drilling fluid pressure, which prevents mud loss failure and provides stability through the borehole. HDD contractors and engineers should consider applying a drilling fluid management system to achieve a targeted drilling fluid rheology and to predict the mechanical behavior of drilling fluid as it interacts with soil in the borehole. Effective drilling fluid management provides the necessary information to monitor and control risk events resulting from elevated annular pressures during HDD construction. To accomplish this, the circulating drilling fluid pressure (plan pressure) must be predicted, which can be done via the appropriate flow model and associated parameters.