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The treatment separation of the mud cleaner by the large of drilling cuttings from the well, so that, mud enter into the next separation equipment, the performance and using of mud cleaner are directly influence the next using effect of the separation equipment. The screen is according to the vibration theory of the liner motion ‘s movement locus to designed, the exciter make the screen box do back and forth movement, the solid particles in the mud is sifted out from the surface, to achieve the purpose of the solid and liquid separation.

The use and maintenance of the drilling fluid mud cleaner

1 The method of use

The correct install and use of the multifunction cyclone mud cleaner can rid of the harmful solid phase effectively in the drilling fluid, control the viscosity, recover the useful solid phase, it has important significance to extend the life time of the mud cleaner and reduce the labor intensity of the field workers.

(1)The multifunction cyclone is installed behind the shale shaker and above the one and two drilling fluid tanks.

(2) The drilling fluid which into the mud cleaner must processed by the shale shaker.

(3) Plugged, after the motor starting, the direction of rotation of the motor and the direction of the sign of belt cover must be consistent.

(4) Firstly, air transportation the rotating shale shaker, then check up it, if found has unusual noise, we should stop to overhaul.

(5) Tightenting the screen, pressuring the spiral, testing pressure the screen by hand, then test running 2-3min, the screen should not have separate oneself from the strip, then appropriate pressure the spirals, inspecting the each tensioning spring, the length should be basically same.

(6) In the process of the using screen, if we need to clean the cumulative sand on the screen, we can’t use spade to sweep the screen.

(7) we should wash the screen at least per shift, prevent the viscous things or sand on the screen are maybe blocked the mesh, influence the screen normal use.

(8)When stop to use it , we should closed sand pump firstly, keep the shale shaker rotating 3-5min and wash the screen in time to keep the screen clean, the closed the shale shaker.

(9)we should Infusing butter on the bearing of the exciter once a day at least.

(10)In the process of transportation or lifting, we can’t put the hard things on the screen or trample by foot.

(11)preventing the sundry enter into the swirler.

(12)we should often wash the discharge grove and the baseboard of the shale shaker.

(13)according the stratum and the property of drilling fluid to select the screen, if the viscosity is high and the sediment concentration is big, we should select the less mesh screen.

(14) The use method of the discharge pipes

the use of the cyclone tube; when the feed liquid pressure equal to the rated pressure, turn off the valve on the overflow tube, make the tubular value of the overflow pipe is 0.01-0.03mpa. When the feed pressure below the rated pressure, adjust the valve on the overflow , make the tubular value of the overflow pipe is .0.02-0.05mpa,


usually, it operate 500h we should maintain it, the main part are rotating part, tensioning the firmware and replace part of lose efficacy components.

It operate 4000h, it need to overhaul, the main content is maintenance the cleaner all sided, replace the cone, check the insulation of the electrical machine , lubrication or tensioning all parts, at last we should paint the anticorrosion treatment.


When drilling the air layer, because the rocks are destroyed, the gap of the rock have a large of gas to immersion the drilling fluid reach the big crack or cave gas reservoir. It is maybe appear the large of gas of replacement immerse the drilling fluid.

1 Characteristics

(1)The density of the different of depth of the gas invasion is different .

(2)The density of the gas invasion drilling fluid will be very small when it is close to the ground, even if the drilling fluid gas invasion of the ground is very serious, the density is reduced, but the decrease of the pressure of the drilling fluid column is not very big, this time we can’t use the density of the ground gas invasion multiplied by the depth of the well to calculation the liquid column pressure.

(3)Because of long time to stop cycle (change the rig head, maintain the pump or electrical logging and so on), there is a large of gas column which is formed by nature gas under the well, when it rise to expansion, maybe led to the drilling fluid overflow.\

(4)After the drilling fluid gas invasion and closed, because the density difference, the nature gas will slip up, finally accumulate on the well month.

(5)In the case of the gas rise but it is not expansion , the pressure of the ground unequal to the pressure of the well month plus to the pressure of drilling fluid column, so we can’t use this pressure to calculate the required drilling fluid density.

2The damage of the gas invasion

(1)Reduce the density of the drilling fluid, after the drilling fluid density reduced, if the liquid column pressure is inferior to the ground pressure, it is maybe led to the well kick or blowout

(2)Make the absorption of the desander pump, priming pump and the drilling pump is bad, even can’t work normally, cause the device vibrate.

(3)Part of the toxic gas overflow from the drilling fluid, the operating personnel maybe poisoning.

(4)It can lead to fire.

(5)After the gas invasion, drilling fluid density will be increased, make the mechanical drilling rate decreased.

So how do we processing the gas invasion ?

The common methods of disposed the gas invasion

1 Circulation drilling fluid degassing method

It use the mechanical equipment continuously circulation drilling fluid on the ground, make the bubbles emersion the liquid level and overflow, the method only rid of the bid bubbles. The bubbles of diameter of less than 1mm, especially the bubbles of high viscosity, the foundation of cycle degassing is small. When use the methods to degassing, in order to reach the degassing effect, required long times, the drilling industrial is not allowed.

2 Chemical degassing method

Adding chemical gas degassing to the drilling fluid gas invasion, the method adopt to rid of the own bubbles. Use the chemical degassing method, need to mix and the time of reaction, so need long time, the high cost. The foundation is small to the gas of external invasion.

3mechanical degassing metood

Using all kinds of mechanical equipment, according the degasser clear the gas which immersing the drilling fluid. The methods apply to all kinds of the drilling fluid degassing. The mechanical degassing divided into ordinary pressure, vacuum type and the centrifugal.


The degassers are used to clean the gas in the drilling fluid, to ensure the drilling fluid property relatively stable, to guarantee the steady operation of swirlers. The degassers can be grouped into two kinds: ordinary pressure type and vacuum type. The ordinary pressure degasser is to use the centrifugal to take out gas to invade the mud, with the help of centrifugal force to make the mud spraying in the jet tanks and striking on the wall to make gas releasing. The vacuum degasser is to use the suction of the centrifugal, forming negative pressure in the vacuum tanks, under the action of drilling fluid at atmospheric pressure, through the suction pipe into the hollow shaft, then by umbrella piece of around the hollow shaft assembly, they jet to the skin of tank.

the picture of factory

Vaccum Degasser  is used to remove the small entrained gas bubbles left in the mud by the mud/gas separator. These units are positioned downstream from mud/gas separators, gumbo removal equipments (if utilized), shale shakers and mud conditioners (if utilized), while hydrocyclone desander and follow in the arrangement. decanting centrifugals follow in the arrangement.

When to use vacuum deaeration?

In installations with many branches and low flow rates.
For small temperature differences between supply and return. A vacuum degasser is not limited by the fluid temperature.
If a deaerator cannot be mounted on the installation for practical reasons. A vacuum degasser can be connected to almost every part of an installation
 TangShan Dachuan Mechanical Equipment Co., Ltd. is a company focuses on the production, sales and after-sales maintenance service of solid control equipment of petroleum drilling (not excavation). The main products are mud vibrating screen, vacuum degasser, desander, disilter, mud cleaner, mud gas seperator, mud agitator, desander pump, shear pump, centrifugal, flare lgnition device, mix funnel, jet mud mixer, mud tank, water tank, diesel tank, etc.
We will always supply the drilling fluid system, the parts and the technology service to ensure the efficiency in the production of our customers. Our tenet is, making the advanced technology, ensuring the good quality, and offering the best service.

1The water ring type of the vacuum degasser in the process of working, always in the constant temperature to work, the performance of safety is high.

2 Use the belt to drive, avoid the complexity of the deceleration institutions.

3 Two levels of the separation gas and the tank is the assembly, the structure is compact.
4 the mud through the window of the trochanteric spray to the wall of the tank, the effect of the degassing is good

DCLW horizontal type helical-conveyer centrifugal is a mechine to separate the soild particles and liquid or separate the liquid and mixture mixed in the liquid by centrifugal force. The main function of centrifugal is to separate the liquid and solid particles in the suspension, or to separate the two kind of different liquid with different density which can not dissolve in each other in the emulsion. And also, can be used to remove the liquid from the mixture of liquid and solid. Some sedimentation centrifuge also can classificate the solid particles in the fluid with different density or granularity by identify the different sedimentation velocities.        

The main components of the spiral sedimentation centrifugal

1 The drum

The drums usually made of the drum barrels and the end covers, the drum barrel conical part is easy to abrade, in order to reduce the wear, there are some fillets along the line. There is a pivot on the drum big end, it is convenient to support the base bearing. The pivot connection with the drum by the flange, the end cover has a overflow month, the other end has a small end cover connection with the small end to support on the bearing.

2 Rotational flow propeller

The rotational flow rotational made of helical blade, inner tank, Charging bulkhead and the shaft neck. The helical blade take measures of abrasion resistant, such as; the abrasion resistant alloy, abrasion resistant plastic, and ect.

 3 The overload protection device

The main engine of the centrifugal provides the separation power, at the same time provide the power to the screw conveyor, when transport a large number of desiltings or the metal foreign body drop in the drum inside card main screw, it can maybe destroyed the planet differential. In order to prevent the spiral and the differential mechanism are damaged, the centrifugal specialized the overload protection device. The over load protection has the mechanical, mechanical hydraulic, electronic mechanical and the electronic overload protection device and ect, but the mechanical is widely used.

4The rotation device

Now, the rotation device of centrifugal are widely used the planetary gear rotation device, and the involute gear differential mechanism is the primary, the 2k-h is popularly.

5 The hydraulic coupler

In order to control the overload of the centrifugal , and make it smooth starting, the movement meet the requirement of the speed regulation, so in the rotation system of the centrifugal is widely used the hydraulic coupler.

Mud Cleaner is the second class and the third class solid control equipment, which is the newest type to treat the drilling fluid. GN drilling mud cleaner are combined from Desander, Desilter and an Underflow Screen, at the same time Mud cleaner has the higher cleaning function  compared with separated desander and desilter. In addition to the reasonable design process, it equals another shale shaker . GN mud cleaner structure is compact, it occupy small space and the function is powerful. Mud cleaner is the ideal device of the second class and the third class solid control to treat the drilling mud.

DC combination of mud cleaner, including  desander, deserter, pressure gage, hydrocyclone, bottom flow slot, shale shaker, stents and pedestal. The characteristics is : between the main into pipes and main out pipes have no control deceleration insitutionsm, there are spout in the pedestal, the screen located in the spout, it is easy to use and maintain, working reliable, can remove the harmful phase quickly, improve the performance of drilling fluid, meet the requirement of the new technology of high pressure spar.

The treatment separation of the mud cleaner by the large of drilling cuttings from the well, so that, mud enter into the next separation equipment, the performance and using of mud cleaner are directly influence the next using effect of the separation equipment. The screen is according to the vibration theory of the liner motion ‘s movement locus to designed, the exciter make the screen box do back and forth movement, the solid particles in the mud is sifted out from the surface, to achieve the purpose of the solid and liquid separation.


1It is a necessary equipment of deep well and super deep well disposed the aggravation of drilling fluid, it can remove the super fine solid phase in aggravation of fluid.

2 It can effectively control the content of aggravation of drilling fluid, to prevent the pressure difference the post card, adhesion the post card and other accidents, reduce the bond issues of drilling string and the thickness.

3 Save the drilling cost

4 Improved the drilling environment

The shale shaker is the most important equipment in the drilling fluid solid control system, it is the first process of the mud purification. Not only using in deep well, but also using the shallow well, the mud must through the shale shaker to filter.

Working principle

The shale shakers are mainly drive by the electrical machine to rotate to produce the periodic changed inertia force, drilling fluid solid phase enters into the sieve screen, do the throwing movement on the sieve surface, and then the solid phase particles with different size will be removed. The separation diameters and throughput of the shale shakers are the most important factors of matching. The technology level of shale shakers mainly show at the handing ability (throughput and separated granularity), the stability of working, the length of life and the flexibility of operation. The handing ability of shale shakers is related with the structure of shale shakers, the movement locus, the vibration frequency, the vibration intensity, the area of shale shakers and the degree of thickness. In order to make the shale shakers match with the drilling machineries, the maximum displacement of the drilling pumps and the quantity of drilling cuttings produced must be considered.


Usually according to the movement locus, the shale shakers can be grouped into round screen shaker, the common elliptic screen shaker, linear screen shaker, equilibrium elliptic screen shaker. The common elliptic screen shaker: also can be called the disequilibrium elliptic screen shaker, there is a exciter devices fixed right above of the screen box barycenter, It requires the screen boxes tilt an angle, gets rid of sand by gravity, avoids the sand having the tendency of backward throwing. From this, the tilt of the screen boxes really improved the moving performance of sand, but the disposed amount of the drilling fluid reduced, this is the main shortcoming of the common elliptic screen shaker. The linear shale shakers

liner shale shaker

: Two main axises with eccentric blocks do synchronous reverse rotation to produce the liner vibration. Because the direction of the liner shale shaker is unchanged,  which makes the particles difficult to drop, and then the screen paste phenomenon appeares, which makes the valid over flowing area of screen  and throughput reduced. When the number of  screens increases, the phenomenon of screen paste will be more serious. So when the linear shale shakers use the super details screen, it could not meet the requirements of the using amount of drilling fluid.

The equilibrium ellipse screen: In recent years to develop a new type screen, the movement locus of long axis and short axis are all the same, the size and direction of the throwing angle are completely consistent. The equilibrium ellipse screen combined with the basic advantages of the round screens and liner screens, the throughput of the equilibrium ellipse screens is bigger twenty percent to thirty percent than the liner screens, is a relatively advanced drilling fluid shale shaker screens, representative the development direction of the drilling fluid shale shakers.