Monthly Archives: June 2016

How to operate centrifugal pump to prevent cavitation

The formation of cavitation will have some negative effects on the work of the centrifugal sand pump. For example, it will speed up the destruction of the centrifugal pump impeller and other metal components. It will aslo cause noise and  vibration in the process of work and cause the decrease of working parameters of cemtrifugal pump. Therefore, in order to prevent the formation of cavitation, te operation of the centrifugal pump need to put forward the following requirements:


(1) The inlet valve must be fully opened when the centrifugal pump is operating.

(2) It is not easy to form cavitation at a low flow rate.

(3) The higher the centrifugal sand pump is installed, the  more cushy to  come into being cavitation.

(4) When the temperature of the drilling fluid is high, it is possible to form cavitation.

(5) It is possible to have the cavitaton in the centrifugal pump if the density of the drilling fluid is high.

(6) Screen plugs of the centrifugal pump is one reason of generating cavitation.

(7) It may produce cacitation when the surface of the drilling fluid is too low.

New type steel frame screen for sale

The steel frame screen and the combination of 2 to 3 layers of stainless steel mesh in the framework of the constitution of the type of screen features are as follows:

(1) The screen nets with different mesh size, accurate and reasonable collocation and the screening effect is more careful.


(2) High strength steel frame and the support bar, and Chang appropriately tight mesh, forming a reliable overall, greatly enhanced the screen can withstand flow, strength and service life. Fast tensioning device to make the screen wedge installation is more convenient, saves the replacement time.

(3) The screen cloth is divided into a plurality of independent small mesh surface, which can prevent the partial breakage and excessive expansion. At the same time to be equipped with a special rubber plug repair damaged, which can save time, and reduce cost.

Reliable oil and gas transportation tool – screw pump

In the oil and gas industry, there are a lot of oil, gas and water need to be transported and transferred to different storage tanks or processing tanks at all times. In the long period of high strength, the shortcomings of ordinary centrifugal pump being exposed slowly, which gives oil and gas enterprises to bring no small trouble, if the loss is greater.

The reliable pumping principle of screw pump provides a better solution for these problems. The structure of the screw pump comprises a helical metal rotor. The rotor is rotated in a double helix elastic stator. When they are combined together to form a sealed cavity, the seal chamber can be rotated in the rotor from the suction side with the rotation has been running to the end of the export. Screw pump using the gear structure of the general connection, can effectively solve the pressure caused by the pump pressure caused by the radial load and axial load. The balance design of the ring gear and the spherical gear, with the valve plate and the stress is distributed over a larger area, but not in the pin or the connection. This greatly reduces the wear and tear, so that the overall performance of the pump better, especially in the sudden abnormal conditions.

screw pumps

The general connection mode of screw pump gear structure can effectively solve the problems of radial load and axial load, so that the pump efficiency is maximized and the service life is prolonged. It has the characteristics of high efficiency, low cost, no sand hanging, corrosion resistance, mild flow and so on. It will not be similar to the characteristics of pulse flow, so that the screw pump has become a tool to transport oil and gas. Screw pump reliable design will not be affected by the mutation, and compared to other pumps, the total cost of the screw pump is the lowest.


Advantages and disadvantages of oil based drilling fluid

Oil based drilling fluid is the drilling fluid which use oil as a continuous phase. It is divided into whole oil based drilling fluid and oil water emulsion drilling fluid. Water is a useless component in the whole oil based drilling fluid, and its water content should not exceed 10%, while the water in the oil – water – based drilling fluid is a necessary component to disperse in the diesel oil, the water content is generally 10%~60%.

Advantages and disadvantages of oil based drilling fluid:
1. Compared with water-based drilling fluid, oil based drilling fluid has the advantages of high temperature resistance, anti salt calcium influx, be conducive to wellbore stability, good lubrication and less damage to the oil and gas reservoirs.
2. At present, it has become an important method for drilling high temperature deep well, high angle directional well, horizontal well and complex formation, and it can be widely used as a solution for the reservoir, the perforation completion fluid, the well fluid and the coring fluid.
3. Allocation cost of oil based drilling fluid is much higher than the water-based drilling fluid, and it will often cause serious influence to the ecological environment near the well site when using the oil based drilling fluid.
4. In order to improve the drilling speed, from the mid twentieth Century to the beginning of the 70’s, low gum oil emulsion drilling fluid has been used in a wide range.
5. To protect the environment and adapt to the needs of marine drilling, from the beginning of the 80’s, it is gradually promoted to use the low toxicity oil emulsion drilling fluid of which mineral oil is the base oil.

Making use of liquid gas separator during drilling

Liquid gas separator adopts anti hydrogen sulfide material and drilling liquid gas separator using high quality materials made by modern technology, this device can effectively prevent the erosion caused by harmful gases in the drilling fluid, and finally to ensure the safety of personnel and equipment. When construction, some toxic and harmful gases carried by drilling fluid carrying will be carried up. For these reasons will cause the proportion and viscosity of drilling fluid get large deviation, unable to meet the drilling requirements; And sometimes serious problems if not timely treatment will cause well kick, or even a blowout accident. The smooth progress of the drilling process can be ensured when the liquid gas separator is used together with the electronic ignition device. Design concept of liquid gas separator for separating mud contained a large amount of dissolved gas and free gas, and because these gases will expand at normal pressure. So the traditional liquid gas separator placed between the throttle manifolds and shale shaker, connected to a pipe dedicated for exhaust gas.
mud-gas-separator1 (2)

Liquid gas separator should generally be required to meet the following requirements:
Liquid gas separator inlet pipe diameter should be equal to or greater than the diameter of the throttle manifold discharge pipeline.
The inner diameter of the slurry discharge pipeline of the liquid gas separator shall be not less than the inside diameter of the inlet pipe, and the slurry is directly discharged into the inlet pipe of the vibrating screen or the slurry storage tank.
According to the practical experience, the processing capacity of the liquid gas separator must be 5 times as much as the design cycle.

The development trend of mud zero discharge managemet

Waste drilling fluid is one of the main pollutants in the oil industry. In recent years, with the increasing demand of energy in the world, the types of drilling fluids are increasing, and the harmful components and the additives are also increasing. According to the statistics, the waste drilling fluid produced annually in our country is about 2500-3200 million cubic meters, of which the 1/2 directly discharged into the surrounding environment, the ecological damage is increasingly serious, and the harmless treatment of waste drilling fluid is imminent.


With the increase of environmental protection requirements, the corresponding treatment has been carried out in various countries. According to the different treatments and discharges between domestic and foreign, waste mud management methods are also many and varied, and the effect of each are not identical, including curing treatment method, chemically enhanced solid-liquid separation technology, mechanical dehydration method, recovery circulation and usage method, safety landfill burial etc. Technology of harmless treatment by curing process is one of the methods to be used more, but it just do the conventional treatment of inhibition and conversion to the waste drilliing fluid, the pollution of the environment is still serious by this method. And then with it, the drilling fluid mud not landing treatment process opens up a new chapter of waste mud management.

Adverse effects of excessive solid content in slurry

The existence of excessive useless solid phase in mud is the biggest hidden trouble to destroy the performance of drilling fluid, reduce drilling speed and lead to complex situations in all kinds of wells. People in the long-term practice and continuous research, summed it up that the high content of useless solid phase in drilling fluid will bring the following several points of adverse effect for drilling works.

1.The influence of solid phase to drilling speed

When the mud solid content is high, the ability to carry the drilling cuttings is weakened, a large number of large particles can not be discharged out of the well hole, causing the bit to broken bits repeatly, and thus increasing the wear of drilling tool, thereby affecting the drilling speed.

  1. The influence of solid phase to mud cake quality

During the drilling process, the amount of water loss and solid particle content will directly affect the quality of mud cake formed in the hole wall. A small amount of fluid loss, mud cake is thin and tough and will do good protection for the well wall,  which is our goal. High solid content, water loss of slurry increases, resulting in shale formation water hydration swelling and hole wall instability, and induce the hole accident.

drilling fluid7

  1. The influence of solid phase to circulation system

The higher the solid phase content is, the more the mechanical wear of the circulatory system will be. Too much solid phase in the mud will accelerate the wear of mud pump cylinder and piston, thereby increasing the maintenance time and lead to the decrease of the drilling efficiency. Drilling efficiency will be significantly reduced due to the increase of the auxiliary operation.

  1. The increase of waste pulp displacement, causing environmental pollution

In the process of drilling, the performance of the drilling can be changed due to the cuttings entering into the drilling mud continuously. Most of the mud is belong to alkaline solution, random emissions will not only destroy the vegetation, but also cause the alkalization of soil, and influence the vegetation regeneration. In addition, There are some additives in the drilling mud so that the color of mud will change into black, a large number of emissions will cause visual pollution to environment.

Purification procedure of drilling fluid solid control system

The larger harmful solid particles in the drilling fluid will be sieved and discharged after the screening of shale shaker.

The drilling fluid that has been purified by shale shaker enter into the sand tank of mud purification tank. And then using the sand pump to join the drilling fluid to the second level purifying equipment—the desander of combined mud cleaner and the drilling fluid will be separated from solids again.

After  excepting sand, drilling fluid discharged into the third storehouse of drilling fluid purifying tank through overflow line of desilter and will be pressured into the third  grade purification equipment—desilter of the combined mud cleaner by desilter sand pump, and be separated again of cyclone principle.

Solid-control-system (2)

The drilling fluid still contains a lot of harmful solid phase after passing a three-stage purifying.  When the drilling fluid is a non weighted state, we use two centrifuge in parallel to remove the harmful solid phase that is larger than 5 μm. When the drilling fluid is weighted, the use of two sets of centrifuge is needed with series connection. After separation the drilling fluid contained barites return drilling fluid purifying tank, and the harmful solids discharged outside the system and achieve the purpose of purifying and maintaining the stability of the drilling fluid performance.

Platform equipped with five levels of drilling fluid purification system equipment to ensure that the platform can meet the requirements of drilling fluid treatment in a variety of circumstances.

Dachuan new type jet mud mixer for sale

When configuring or increasing the total amount of drilling fluid, change the density, viscosity and water loss of drilling fluid, it all need to put the drilling fluid materials (bentonite, barite powder, etc.) and the corresponding chemical additives (polymers) into the circulation tank. The jet mud mixer can increase the shear force of the liquid in the tube, and to increase the material dispersion effect better, improve the pressure head of mixing liquid, so that the material in the tank is fully mixed and circulated, and the use effect will be more outstanding when supporting the use of shearing pump.

Jet mud mixer is a device that supporting the use of oil drilling solid control system, which can meet the requirements of the aggravation and configuring of drilling fluid of different depth of drilling fluid solid control system. The mixed slurry device consists of one  (or more) sand pump and one  (or more) jet mixing funnels which is connected by pipe manifold valve and installed on a base. The funnel and sand pump can be combined or installed splitly, and between the aggravating funnel and the sand pump is the pipe valve connection.


Jet mud mixer is a specialized solids control equipment used for configuring and aggravating drilling fluid, thus change the density, viscosity and pH of drilling fluid.

DC uses venturi tube combined with original jet nozzle created a new design of jet mud devices, it is not only simple in structure, but also have strong feasibility, which can meet the requirements of aggravation and configuration of drilling fluid in drilling solid control system from 1500m to 9000m. We can also produce double jet mud mixers according to customers’ requirements.

Jet mud mixer produced by DC have the advantages of high mixing speed, safe and reliable performance, long service and etc.

Two sets of desilters were delievered to Hongkong

Two set of desilters delivered to Hong kong which are made by 12 hydrocyclones of each machine yesterday.

desilter1Desilter is the third class equipment in solids control system, it is used to separate the solid particles whose diameter is 15-44μm from drilling fluid. The desilter produced by DC Machinery has the advantages of large handling capacity, high separation ability and convenient operation.

Welcome to inquiry if you are looking for this kind of machine.