Screen installation arrangement has two types of tandem and parallel.
- Tandem type installation screen
Tandem installing screen is that the drilling fluid must pass through two or more than two screens with decreasing pore size which are separated from each other by some distance. This arrangement has the advantages of the upper screen firstly screen out the large size ofcuttings, it can protect the more fine screen underlying effectively, especially in fast drilling. And when the solid content of the drilling fluid is increased, lower layer screen will not be overloaded; And the shortcomings of this kind of sieve are that it is not easy to observe the lower layer screen, if the replacement is not timely after being damaged, it will influence the treatment effect of drilling fluid.
Coupled with the inconvenient replacement, only one layer of screen is used in some crew.
- Parallel type installation screen.
Parallel installation screen refers to two or more than two meshes lap together and form a long screen. This type of instalation has the advantages of increasing the treatment capacity and will not let the drilling fluid run away(because of the long screen); When a section of screen is broken, only the broken section needs to be changed. This can save the cost of screen and the replacement is more convenient. The disadvantage is that the structure is complex and the weight of the whole machine is increased.
Horizontal directional drilling mud solid control system is a device and system for controlling the solid particles in the slurry produced by horizontal directional crossing. Dachuan Machinery is a professional manufacturer for horizontal directional.
- Horizontal directional drilling (HDD) technology has obvious advantages in the oil and gas pipelines crossing rivers, lakes, transportation lines, railway hubs and other obstacles and important regions. The diameter of the hole of horizontal directional crossing pipe diameter is generally 1.3 to 1.5 times.
- Horizontal directional drilling through the so-called mud solid control (usually referred to as the solid control) process is to control the solid particles in the mud, the principle and technical methods. Through the solid control technology to remove the harmful solids in the mud, retain the useful solid phase, to meet the requirements of the mud performance through the process. The harmful solid phase in the horizontal directional drilling through the mud is the drilling cuttings which mainly refers to the wear of the equipment and the influence on the rheological properties of the slurry.
- Solid control system used in the horizontal directional crossing: at present, horizontal directional crossing mud solid control recovery system consists of domestic and imported the accounted for half of the country, the import is mainly small, with imported drilling machine matching; domestic is mainly large, according to user needs to be prepared. Whether domestic or imported, the choice of the fixed control system is mainly based on the following principles:
Type and size of particles to be cleared or suppressed;
Through the need to maintain the quality of mud;
The size of drilling rig capacity, solid phase clearance rate and circulation rate.
Tangshan Dachuan solid control is a company specializing in the production of horizontal directional crossing mud system manufacturers, our company engineer with more than a decade of horizontal directional crossing slurry system design and production experience, all the use of my company horizontal directional traveling across the mud system of old and new partners are given from most of the year-round friendly cooperation cully. Our company has a mature production process and quality control system.
According to the different characteristics, there are different classification methods of the solid phase in drilling fluid.
- According to the role of solid phase in the drilling fluid, it is divided into useful solid and harmful solid phase.
- The solid phase is divided into high density solid phase and low density solid phase according to the density of the solid phase. High density phase is the weighted materials based on the drilling process requirements to increase the density of the drilling fluid, low density phase including the bentonite and treatment agent that required by configuration of the drilling fluid, and there are cuttings.
- By whether solid phase and liquid phase is reacted, the solid phase in drilling fluid is divided into active solid phase and inert solid phase. The solid phase that can react with liquid is called active solid phase, and can not react with liquid is called inert solid phase. The former such as bentonite, clay and shale, etc, or such as limestone, granite, barite etc.
Jet mud mixer is a new type of mixer which consists of feeding hopper, butterfly valve,mixing barrel, floe meter, vortex volute and large displacement of centrifugal pump.
The sand pump pumps the liquid that need to be mixed into the swirl volute along the tangential direction, high-speed rotation liquid in the volute creates a vacuum which inhales the mixed materials and then enter into the mixed tank after being blended with the high –speed rotation liquid. High –speed rotating liquid flow will blend the materials with the fluid fully in the inner cavity of the mixing barrel, after that they go into the outer cavity of the mixing barrel of the swirl mud mixer and then discharged along tangent direction, then the mixing process of a periodic cycle is completed.
The jet mud mixer has the following characteristics:
Long effevtive mixing time and better mixing effect; the feeding caliber is large so it is not easy to be blocked, the feeding speend of the jet mud mixer is fast and it has strong adastability fo materials. It has the wide application and will not extend the time to stop so that the phenomenon of solid phase deposition will not occur.
Jet mud mixer is usually composed of one set of centrifugal pump and a set of jet mixing hopper, which is connected by pipe manifold valve to install on single jet mixing device that is composed of a base. Or two sets of pumps and two sets of mixing hopper composed a double jet mixing pump.
Generally speaking, if want to enhance treating capacity, we can depend on increasing work pressure and changing a larger spray nozzle to realize. And experiments show that increasing the nozzle diameter and inlet flow rate is a more economical method.
Main factors affecting on jet mud mixer performance
1. Reduce hydraulic edge of mixing hopper loss as far as possible, or may lower treating capacity greatly.
2. The distance from pray nozzle to venturi tube should be suitable, the best distance is to keep at 32-90mm, usually can’t exceed 90mm, otherwise, the feeding speed of barite will be decreased significantly.
3. The back pressure of the outlet pipe should be suitable, the larger back pressure will reduce the processing capacity of the mixing hopper.
For example, when the nozzle outlet diameter is 50mm, the gap between the nozzle and the venturi tube is 90mm and the working pressure head of the mixing hopper is 21-23m. The mixing chamber has a high vacuum value before the pressure value is reached 50%. But when back pressure close to the inlet pressure 50%, the vacuum degree is almost zero and drilling fluid start back-flow in the hopper.
4. The larger inlet pressure, the larger treating capacity of mixing hopper.
5. The higher for mixing hopper installation, the higher back pressure and mixing ability will be decreased.
Recent days we are delivering an aggravating tank to one of our clients from Pakistan.
Aggravating tank is one of the drilling mud tank. The weighted tank is installed in the suction part, it is a type of small tank with typical volume of 3-8 cubic meters. The weighted tank should be separated independently from the circulation system, which is mainly used for a small amount of special fluid. Some of the drilling fluid system may install more than one weighted tank. They should be collected with the charging hopper by manifold, which is convenient for the addition of solid phase and chemical additives, it also used to prepare a more heavy drilling fluid. In order to prevent the drilling fluid in the drill pipe to splash on the platform in the drilling process, this drilling fluid should be joined up before drilling. These tanks also be used to mix chemical additives or water – based drilling fluid.
Weighted tank must use manifold to connect with the main suction tank through the centrifugal pump . If there are many defferent kinds of driling fluid during the drilling process needs to be mixed at the same time, we must conduct appropriate agitation to the aggravating tank, especially use one or a plurality of drilling mud guns incidentally will be more conducive to prevent the particles deposited in the bottom of the tank and the dead angle, and make the stirring more uniform.
The work principle of hydrocyclones is to separate two or several components with different densities with the aid of centrifugal force. After the mixture is sent into hydrocyclones by certain pressure, it gradually flow into a high-speed rotation where the heavy phase form an outer swirl by moving downwards along the axis, outwards along radial direction, downwards again along the cone till they flow out of underflow; while the light phase form upward inner swirl by moving towards axis and upwards till they go out from overflow outlet. Thus, the separation is done.
Sand fill is the commonest anormaly to hydrocyclone and is categorized as:
Sand fill at the underflow: it happens as a consequence of improper adjustment that results in dry bottom or of excessive silt content which brings about overloaded hydrocyclone. It should be removed immediately as it affects the purification ability and accelerates abrasion of lining and vortex tube. Usually the best ways are to enlarge underflow outlet or to have more solids taken away by preceding equipment.
Sand fill at the inlet: it can be partial or overall. Partial sand fill decelerates fluid flow inside inlet, leaks enormous drilling fluids from underflow and sometimes clean mud which may flow backwards from the overflow as, at that time, hydrocyclone is not more functional than a hopper. Overall sand fill is prone to back flow drilling mud from the overflow. Inlet sand fill generally stems from poor drilling fluids management, and most likely from going round the shale shaker or abrading shaker screens.
Linear motion shaker uses vibration motor as vibration source enables the fluids to be thrown up on the screen, forward in a straight line at the same time. The material is from the feeder evenly into the sieving machine, producing number of different microns particles and discharged by different exports.
Shale shake adopt double vibrating motors. When two motors reverse rotation synchronously, producing the exciting force in the parallel direction cancelling out to act as a force in perpendicular to the motor. So the vibrating track is linear all the time. Two motors have a dip in relatively side. Under both vibrator and mud fluids strength, the material in the shaker screen leap forward for linear motion. So as to achieve the purpose of screening and classification of materials.
It can be used to realize the automated assembly line in operation. The shale shaker has many advantages, like high strength vibration large screening area, little nose, excellent performance and high efficiency. Easy to operate, install and maintain. Making perfect mechanical steal, dust overflow and automatic nesting insure high efficiency, high performance by pipelining working
(1) A variety of gear box and impellers combination of the agitator can meet most of the needs;
(2) Mud agitator has high efficiency in deep and large containers;
(3) The mud agitator can be designed for a suitable shear force according to the need;
(4) Mud agitator make more fluid exposured to touch air, to help cool the drilling fluid.
(1) The mud agitator can not mix the drilling fluid in different containers, it also can not transfer drilling fluid between the two containers;
(2)The mud agitaor needs power supply at most time;
(3) There may be fade zone (dead zone or dead point);
(4) It may require the installation of partitions.
Drilling fluid solids control centrifuge generate centrifugal force of high speed ratation by the rotor of motor which can accelerate the settling velocity of the solid particles in the liquid phase, and the solid particles with different sedimentation coefficient and buoyancy density are separated. The slag pushing job of the drilling fluid solids control centrifuge is accomplished by the propeller.
Under the action of the differential, a certain speed difference formed between the screw propeller and the roller, the solid particles that have been settled to the cylinder wall are scraped away from the cylinder wall and then pushed to a small end of the roller by the helical blades, and are dehydrated during propulsion process, solids particles reach the sand spray nozzle finally and are thrown ot of the roller, then the four-class treatment of drilling mud solids control is completed.
Installation procedure of drilling fluid solids control centrifuge:
- The drilling fluid solids control centrifuge should be firmly installed at the place where is far from the entrance of the drilling pump in order to ensure that the recovery of liquid phase can be fully stirred.
- It should be sure that the drilling fluid solids control centrifuge is fixed firmly, the four legs of the bracket should be fixed on the position of the tank surface that with a supporting beam position.
- It should be ensured that the sand drain tank can be extended out to the tank to make it easy to drain sand during the installation of drilling fluid solids control centrifuge , and connect the water supply line well on the sand drain tank to ensure sand draining smoothly.
- The drilling fluid pump should be installed in the proper position after cyclone desander and mud desilter, and connect the feeding pipe to the inlet pipe joint right.
- Connect the flushing water supply pipe and shunt tube on the inlet pipe and box body right.
- Turn on thepower supply. There should be switch controling between the control box to the power supply of the drilling fluid solids control centrifuge to ensure the safety of maintenance.