Tag Archives: solids control

Definitions of Drilling Fluid Solids Control

In well drilling, we often hear various drilling fluid solids control related terms. Then, what do they mean?

1) Solid Phase Volume

The total insoluble solid drilling fluid, usually expressed as a percentage by volume. The solid phase volume of high density drilling fluid including low density and high density solid. Solid amount of conventional drilling fluid are low density solid.

 

2) Low Density Solid

These solids including clay powder and cuttings as goods. Usually in the solid control work assumes that its density is 2.60 or 2.65g/cm3, this assumption has been able to obtain satisfactory results, the actual value may fluctuate between 2.0~3.0g/cm3.

 

3) Density

Density is the volume in mass per unit. The unit can be used g/cm3. Drilling fluid is composed of different density materials. In the past, the proportion of common concept, now is no longer in use. In solids control system, solids control equipments like desander and desilter are used for adjusting the density of drilling fluid.

desander

4) Cuttings

Drilling is the main solid contamination of drilling fluid, it greatly affects the performance of drilling fluid, must be stable, and therefore can be an important problem in the process of drilling to conventional drilling fluids treatment. Solid control is the control of drill cuttings. Has the direct relationship between the drilling cost and solid control and its effect.

The composition and maintenance of mud shale shaker

Mainly by the mud shale shaker: vibrating motor, compound rubber spring, stainless steel screen, screen box and a start switch.The product through the vibration motor drives the eccentric block to rotate at high speed, the eccentric block to rotate the centrifugal force generated strong effect on elastic oscillator, which is fixed on the flat plate frame screen screen frame at the bottom of the vibration sieve to higher frequency, higher drilling cuttings.

shale shaker

Vibration sieve in the oil and gas drilling, non excavation in a very important position in engineering, coal-bed methane development, shield, river dredging, mud recycling system.

In order to enhance the service life of the shale shaker, attention should be paid to the use of notes and daily maintenance.

First, take over whether leakage logging can import inspection vibration sieve, and according to the requirements. The inlet connecting pipe. Each shift with a water hose to sediment generation equipment operation process from the device wall and sieve bed clean. These deposits will increase the damping block load and reduce the ability of vibrating screen separation of solid particles. Each shift once or inspect screen wedge fast fixed and working state. And the screen may not have holes or other defects, otherwise, the solid particles may loss. If the screen is damaged, should be replaced in a timely manner.

Second, in the use process, if found to have occurred in drilling fluid, should be timely.

shaler screen

Third, stop running vibration sieve, should be promptly shaker screen, and drilling fluid brush brush clean screen and embedded in the mesh in the sand. In the process of drilling mud shaker has stopped functioning, and because of long time no circulating drilling fluid viscosity, often up to more than 100, when the mud into screen slot through the valve is opened, and at the same time close flash board inlet end of the vibration screen, prevent the drilling fluid with high viscosity and flow to the screen surface. Screen cataplasm to death. If the board closed lax, the drilling fluid into the screen, should be promptly rinse screen.

Fourth, lifting, no foot and smashing pressure screen, the transport process is strictly prohibited any item screen. Hoisting and transportation must be 4 M20 × 110 bolts to mud shaker screen box and the base are fixed, to prevent the damage caused by the violent vibration shaker box.

The working principle of Brightway decanter centrifuge

Brightway decanter centrifuge used in solid phase concentrations of solid particle size 2-7 μ m, drilling mud is 2 ~ 40%, the drilling mud liquid relative viscosity and separation and containing a small amount of solid liquid separation of 30s suspensions. Mainly used in oil and gas drilling non excavation, shield, dredging engineering, able to complete the solid, liquid, dehydration separation process.

decanter centrifuge

BWLWF series horizontal centrifuge, by two at the same time, to the drive motor, the main motor through a belt drive, drive the drum and the differential housing operation, the auxiliary motor through a differential gear drive, the screw shaft inside the. So that the drum and spiral shaft rotation in the same direction movement; and reaches a certain speed difference. Drum diameter generally divided into 450mm and 355mm two, because the speed decided to separate the effect of the equipment, so the higher the speed, the better the separation effect. The centrifuge is divided into components, base, screw axis, conversion, the outer box body, differential, main and auxiliary motors, electric control, various connecting pipe manifold.

BWLWF series horizontal spiral centrifuge is according to the characteristics of oil and gas drilling mud solid, professional to design separation equipment. BWLWF series centrifuge is mainly used for recovering barite powder, solid particle filter tiny, reduce drilling mud solid to the content, so as to control the density of the drilling mud viscosity, in a certain range, to ensure the performance of drilling mud, do not change. To achieve a sustained effect of cycle use.

The processing ability of the hydrocyclone

Brightway desander is solid management second level system of solid management instrumentation, the most role is to solid particle filter 47~76um. Sand removing cyclone relies on the principle of centrifugal gravity to get rid of solid particles in drilling muds. lubricating substance is fed into the impact of sand removal when Cyclone For mation of swirl flow in cyclone, cyclone mud is mirrored all told directions, by centrifugal gravity made, deposition of solid particles within the vertebrae at the hydrocyclone, the bone body discharge to the vibration sieve. And was refined from the higher a part of the lubricating substance pipes into a suspension storage mud tank solid system.

desander

Besides the benefits into sand hydrocyclone is: import and export manifold with fast joints connecting (maintenance), has the benefits of easy structure, quick replacement, handling capability of sturdy moving flow. The disadvantage isn’t effectively the solid is separated into 2 size vary obvious.

Cyclone sand process capability depends on the scale of the cyclone for removing sand and dust consistence. If the hydrocyclone underflow adjusted, to cyclone for removing sand input while not consistence liquid, no consistence liquid from a suspension pipeline is discharged; and therefore the relative with solid separation, liquid input solid particles discharged from rock bottom outlet, whereas the cyclone below the excretion export adjustment is that the key.

hydrocyclone

 

If the hydrocyclone desander bottom outlet, diameter relative to the balance between zero corresponds to the diameter is just too little and therefore the balance purpose underflow mouth edge region are going to be fashioned while not liquid zone, the alleged non liquid zone is between the equilibrium points and outlet edge solely in solid sand,vertebral wall than the drier. once little gravel lose wet, are going to be terribly straightforward to adhere to the inner wall of the cyclone on the block, this is often not the wrong adjustment mode is named dry bottom. If the discharge port adjusting diameter is larger than the comparable to the equilibrium purpose diameter can result inleakage, the error adjustment that’s referred to as wet bottom

How to ensure that the process of drilling fluids can be achieved within the scope of the design?

Ensure proper drilling fluid density . Only the normal fluid density , will effectively balance the formation pressure to ensure no wall collapse , this is the key to measuring success is guaranteed. First, we must learn from the documents good neighbor wells ; Second, in the high-pressure layer to promptly drilled oil and gas channeling speed measurement ; Third, the estimate is the most important work the pump should stop to observe the situation at the wellhead is there an overflow generated , and the amount of drilling fluid from the drill and poured back out changes are consistent. If you encounter drilled high pressure reservoir , underground normal , the cycle should gradually reduce the density of the drilling fluid to reduce the solids control , lower bottom hole pressure differential.

Here attention is needed to avoid the performance of substantial adjustment of the drilling fluid , and control the performance within the scope of the design , to avoid the formation of a virtual wall , thick mud . In order to form a fine , thin and has a toughness of mud , can now proceed from the following four areas:

1, with a low plastic viscosity while drilling , high dynamic shear force , control motion in 0.5mPa.s more than plastic .

2 , ground out from under the short , especially in the section of wall inclined to avoid the formation of cuttings beds.

3 , make good use of drilling solids control equipment , drilling fluids can effectively reduce harmful solid particles .

4 , adding the right amount of bitumen treatment agent , maintaining wellbore stability .

In the oil drilling process, we must ensure that the drilling fluid technology and good thixotropic , non- stick with a low- cut drilling fluids after drilling stick cut away design limit , improve wellbore cleaning.

Solids control equipment in Trenchless Horizontal Directional

Currently , the Environmental Protection in any industry are a sensitive word , trenchless horizontal directional through mud purification system are the owners of the construction team of the more important requirements, so trenchless horizontal directional trenchless crossing construction units are conducting good value for money to buy configuration mud solids control equipment, which is carried out after the mud again use solid phase separation , in general can achieve good results , but also led to domestic trenchless horizontal directional trenchless crossing mud solids control system rapid development.A trenchless crossing trenchless horizontal directional principles and methods of solid-phase control.

Trenchless Horizontal Directional control through the so-called principle of the solid phase of the slurry is controlled inside the separation of solid particles , leaving a useful solid-liquid mixing mud , through the project to meet the requirements of the mud weight . Trenchless Horizontal Directional large particles through the mud in the solid phase refers to the well field drilling equipment wear , affect the rheological properties of the mud cuttings .

shale shaker

Today trenchless horizontal directional mainland China through the mud solids control system has domestic and imported , but the imported equipment, mainly small, with imports of non- excavation drilling rig supporting good ; domestically is large, is based on customer need to come. Regardless of whether you are domestic or imported good, solid control system mainly based on the following two choices : a need to maintain quality through the mud ; b need to clear the control of particle types and sizes.

What is solids control?

Solids control equipment refers to a well drilling technique accustomed give lubricant to deep well drilling rigs and to scrub this fluid for more use. The technique is commonly known as mud drilling as a result of it uses a flow of water and dust to bring solids out of bore holes and funky the drill rig instrumentation. This lubricant conjointly facilitates the required hydrostatic  pressure to forestall the flow of natural formation fluids into the bore hole. this system has accrued the protection of the well drilling method whereas creating wildcat drilling a cheap possibility.

 

The well drilling processes and strategies of solids management have seen a range of evolutions over time. From easy gravity management solids removal pits to complicated mechanical solids control systems, the varied techniques and instrumentation accustomed take away solids from lubricant have created drilling mud shale shaker doable. With the creation of solids management measures, bore drilling has become way more economical because the drilling resolution is reused.

shale shaker

One of the earliest known  uses of solids management in an exceedingly well drilling method that occurred within the last century. A series of process pits were accustomed capture the lubricant from well drilling rigs. because the fluid passed from one pit to future, it had been allowed to settle. The force of gravity caused the solids to settle out of the liquid. The lubricant may then be channeled to a pump house wherever it had been sent on to the drilling instrumentation for re-use.

The Application Range of Decanting Centrifuge

Decanting centrifuge is a machinery using centrifugal force to separate the mixtures component in liquid and solid particles or liquid and liquid .

Brightway decanting centrifuge

Brightway decanting centrifuge

Decanter centrifuge is mainly used for separating the solid particles and liquid in suspension liquid; or separate two different densities and immiscible liquids in emulsion (such as to separate cream from milk); it can also be used to exclude moisture in solid liquid, such as washing machine spin dry wet clothes; special speeding tubular separator can separate different densities of gas mixtures; settlement speed is different in liquid by use of solid particles of different density or size, some settling centrifuge can also according to the density of solid particles or particle size classification.

The application of centrifugal separation principle in early time was in China. In ancient times, people hold one end of rope and tie the other end of the rope at terrine, rotate swing pots, centrifugal force and generate extrusion of the honey in the terrine.

Nowadays, decanting centrifuge is used in chemical, food, dressing, pharmaceutical, petroleum, water treatment, coal, and shipping department. Meanwhile, in solids control system, this type of solids control equipment also plays an important role.

The Principle of Vacuum Degasser

Vacuum degasser, one of the common solids control equipment, is widely used in well drilling. Then, how it works?

The upper end of liquid level control device gas guide pipe in the conduction path between the air chamber of vacuum degasser, the air guide pipe at the lower end of the float moves upwards under the action of the plunger, the float is not influenced by the external gas pressure difference, when the liquid level rises, float along with the air guide pipe is easy to rise to the height of the corresponding, the action process is following:

Guide air seat installed in the deaerator head, upper guide air seat cavity through the vacuum sealing plug and gas guide seat is axially arranged pores with vacuum tank consistent.

When the liquid level in the vacuum degasser is increased to the liquid level float up, float through the link pin drives the guide tube to move; when the guide hole pipe through the air guide seat is arranged along the radial direction of the hole and the atmosphere at the same time, decline in the vacuum tube, the liquid drop, liquid level float to guide pipe down, guide tube and outside atmosphere between guide gas interface is reduced or closed, to maintain the vacuum degree in the vacuum degasser.

Due to the adoption of vacuum tube upper cavity and vacuum degasser to keep the pressure balance is consistent, can make the conducting pipe interface to increase, this increases the sensitivity of the liquid level control device.

At the same time, vacuum degree to maximize the degasser in vacuum degasser permission, in improving the the initial effect, in addition to the safe operation of the solids control system is guaranteed.

Solids Phase and Solids Control System

When it comes to solids control system, solid phase should be mentioned. The solid phase of drilling indicates the solid elements contained in mud, the percentage for volume or mass is the drilling fluid solids content we usually say.

Drilling solid, according to their functions, can be divided into two categories: the useful and harmful solid phase. Because of liquid solid content, particle size and the cost of drilling have essential relationship, drilling fluid solids control appears to be very important in drilling engineering.

The mud solids control is to remove harmful solid mud in the solid phase and preserve useful solid prase. In order to meet the requirements of drilling technology on mud properties. Usually the mud solids control refers to solids control, mud solids control system is generic term all the mud solids control equipment. Modern mud solids control is an important means of modern drilling, for it directly affects the safety, quality, fast drilling and protection of important factors of oil and gas reservoirs, it is also an important symbol of drilling into the scientific stage.

Specifically, the mud solids control has the following functions: prevent oil and gas channel blocking, damage, reduce the drilling torque and friction, reduce the annular suction pressure fluctuations, reduce the possibility of differential pressure sticking, improving drilling speed, prolong the life of the bit, reduce equipment wear, improve the life of wearing parts of the mud circulation system, increasing borehole stability.

In addition, using drilling mud system such as mud tank and mud shaker will improve the underground conduit conditions, reduce environmental pollution, maintain the performance and adjust the mud, reduce drilling costs.