Monthly Archives: June 2020

Working Principle of Centrifuge in Coal Washing Plant

1. Working Principle of Vertical Vibration Discharge Centrifuge

In general, the vertical and horizontal centrifuge structure is not different, the difference is mainly arranged in different ways, vertical is vertical. The working principle of vertical centrifuge is that the staff put the material into the machine through the funnel, pay attention to the distribution must be evenly when placed. When the machine is running, the material can be thrown into the cone of the sieve basket by centrifugal force at high speed. Among them, because its vibration is axial, its material also moves from top to bottom with the whole sieve surface, and then realizes the separation of solid and liquid. The separated liquid can be discharged through the sink. In addition, the vibration of the machine can keep the material loose  state, so that the overall dehydration effect is more obvious.

2. Working principle of Horizontal vibrating discharge centrifuge

In horizontal high-speed vibration dynamic discharge axial centrifuge, the material is mainly subjected to two axial centrifugal forces. One main force is the axial centrifugal force which rotates at high speed along the rotating direction of the inertia diameter of the vibrating animal material; the other is the centrifugal force which comes from the direction of the inertia axis of the vibrating material along the rotation direction of the material diameter. because the internal \915; centrifugal gravity of the material and the factor of its separation rate are usually much smaller compared with the centrifugal force factor of the material axis upward, the axial centrifugal force factor is negligible.

The direction and numerical value of the two vibrating inertial friction forces on the internal movement of the various materials to be processed can always change. The centrifugal force can C be divided into two forces, that is, Cp and Ct,. The inertial force of vibration can also be decomposed into JP and Jt.. If the result is greater than the friction between the input material and the sieve surface, the material will move outward, that is, the discharge.

3. Working principle of scraper discharge centrifuge

In general, scraper discharge centrifugal opportunities according to the distribution of sieve basket in which the distinction is horizontal and vertical. The operation principle of the machine is mainly through centrifugal force to achieve filtration, when the wet coal enters, it will reach between the sieve basket and the scraper of the screw, and then through centrifugal force, the centrifugal liquid is discharged through the whole material from the screen and into the sink, and finally out of the machine, the material that drains the water will remain inside the screen. But there is a certain speed difference between the sieve basket and the screw scraper, which makes the scraper can scrape out the coal particles and finally get the dry coal.

The spiral corner spacing on the scraper shaft refers to the angle between the trajectory of the centrifuge coal flow motion and the centrifuge sieve strip. at present, assuming that the measured value β=45~60°, the effective width of the sieve seam is determined to be Bβ=b/sinβ(where, b/snβ is the scraper pitch of the centrifuge). It can be seen that the correct selection of appropriate scraper pitch is very important for the dehydration of centrifuges [2]. moreover, the gap between the scraper and the sieve basket is required to be (2±1) mm, this gap can be adjusted by increasing or decreasing the mat on the flange of the shaft or decrease the scraper.

How to Maintain the Decanter Centrifuge

Decanter centrifuge is a continuous operation of settling equipment. Choosing a suitable decanter centrifuge can not only solve the production problem and improve the working efficiency, but also save the production cost and reduce the operating risk. The following is to introduce the main points of maintenance and maintenance of decanter centrifuge.

1. for bag type coarse effect or medium effect filter, under normal use condition, general use 7-9 weeks should replace new.

2. for sub-efficient filters, under normal operating conditions, the general use of 5-6 months, should also be replaced.

3. all kinds of filters before the device, do not promise to open the bag or packaging film; and according to the packing box marked on the biased storage filter; in the handling process, should be light, light release, to prevent violent vibration and collision.

4. for high-efficiency filters, the device bias must be accurate: when using corrugated plate combination filter in vertical device, corrugated plate must be perpendicular to the ground; filter in vertical and frame connection, strictly prohibited leakage, deformation, breakage and leakage of glue, etc., after the device must be wrapped inside clean, free of dust, oil, rust and debris.

5. the high efficiency filter is installed, the arrow on the outer frame should be consistent with the airflow direction; when it is installed vertically, the filter paper crease direction should be perpendicular to the ground.

6. transport and storage of efficient filters shall be shelved in accordance with the direction of the factory signs. Lying screw centrifuge in the transport process, should be light to take light release, to prevent violent vibration and collision, do not allow rough loading and unloading.

7. the high efficiency filter must be unpacked at the installation site before installation for appearance inspection, including: filter paper, sealant and frame damage; side length, diagonal and thickness dimensions meet the requirements; frame with or without burrs and rust spots; with or without product certification, technical performance meets the design requirements. Then according to the standard “clean room construction and acceptance code” the method of inspection, qualified should be installed immediately.

8. the cleanliness level is equal to and higher than the high efficiency filter used in the clean room of class 100, the detected according to the method specified in the clean room construction and acceptance code before installation, and the required requirements shall be met.

To be continued

Structure & Working Principle of Screw Conveyor

The screw conveyor uses the motor to drive the screw to rotate, moving the material to achieve horizontal, inclined or vertical transport, in the material movement direction of the end of the thrust bearing with the material to screw axial reaction, in the long time, the middle hanging bearing should be added.

Structure of the Screw Conveyor:

Screw conveyor in the form of conveying is divided into shaft screw conveyor and shaftless screw conveyor. Axial screw conveyor is composed of screw, U type material slot, cover plate, inlet, outlet and drive device. Axialless screw conveyor is changed to shaftless screw, and in U groove device has replaceable lining body, material is input by feed port and output by outlet after screw push, the whole transmission process can be carried out in a sealed slot.

Spiral blade welded on rotating shaft of screw conveyor, the surface type of blade according to the different conveying materials have solid surface type, belt surface type, one-sided type of blade.

Working Principle of Screw Conveyor:

When the screw shaft of the conveyor rotates, the material can only move forward along the bottom of the conveyor’s groove under the push of the blade because of the gravity of the material and the friction force generated with the groove wall, as if the nut that can not be rotated forward along the rotating screw. The movement of the material in the middle bearing depends on the thrust of the material moving forward behind it. This process needs continuous material feed into the screw conveyor from the inlet port.

In this regard, the delivery of materials in the screw conveyor, is a type of slip motion. In order to keep the screw shaft in a pull state, the drive device and the discharge port are generally placed at the same end of the conveyor to achieve this target, while the feed inlet port is placed as far as possible near the tail of the other end. The rotating screw blade carries the material through, so that the material does not rotate with the screw conveyor blade is the weight of the material itself and the friction resistance of the screw conveyor housing to the material.

GN produces screw conveyors of different capacities, ranging from 15 ton/h to 55 ton/h. At the same time, we can also produce the machine in a customized way to meet clients requirements.

A Simple Understanding of Centrifuge

Centrifuge is a very important instrument used in many fields of industry and chemistry. Its purpose is to achieve the separation of useful or non-material, to ensure that such separation can improve the utilization of substances, and many experiments can be carried out, and all of these benefits, that is, the invention of centrifuges to achieve the results, and people do meet their own application needs.

After finishing the basic introduction of the centrifuge, it is very necessary for us to know the working principle of the centrifuge, to understand, such an instrument is how to achieve separation work, which will help us a lot in using it in the future.

In fact, the working principle of the centrifuge is very simple, it is through the centrifuge inside the rotor through high speed operation, speed up the settlement between liquid and solid later to achieve separation, so this is very simple, but we need to pay attention to the force generated by this rotor, if not strong enough, still can not produce separation effect, so in the design, pay attention to the construction of this part.

Of course, when it comes to this application principle, that is, the natural phenomenon that we will often see in our daily life, and the use of instruments is to transform the natural phenomenon, and through the instrument to complete its separation, so this method is also feasible. It is important to know that the application of centrifuges in human society is indeed huge and vast, so it is useful and good to know such an instrument.

Features:

◎ microcomputer control, AC frequency conversion motor drive, smooth operation, quiet.

 ◎ large liquid crystal display speed, centrifugal rate, temperature and time and other parameters, running can change the parameters at any time, no downtime.

 ◎ can set centrifugal force, RCF value, can be exchanged, can be observed at any time.

 ◎ is provided with a short-time centrifugal special click key.

 ◎10 gear acceleration and deceleration control ,9 gear free stop time can reach 540 s, meet the special separation product use requirements.

displayed in seconds when the ◎ time is less than one minute.

 ◎ adopt electronic door lock, full steel inner cavity protective sleeve.

 ◎ is suitable for the separation and purification of radioimmunoassay, biochemistry, biopharmaceutical and blood products.

If you are interested, please contact us

Mobile : +8615100635311 WhatsApp : +8615100635311

WeChat:+8615100635311 Email: tony@gnseparation.com

Daily Maintenance of Centrifuges

Centrifuge is an instrument for separating samples, which is widely used in biomedical, petrochemical, agriculture, food hygiene and other fields. It uses the difference of precipitation speed of different substances in centrifugal force field to realize the analysis and separation of samples. Since the advent of centrifuge, after the low speed, adjustment, overspeed changes, its progress is mainly reflected in centrifugal equipment and centrifugal technology, the two complement each other.

From the view of rotational speed, table centrifuge basically belongs to the category of low speed and high speed centrifuge, so it has the technical characteristics of low speed and high speed centrifuge, and its structure is mainly composed of motor drive system, refrigeration system, mechanical system, turning head and system control.  Part of the composition, compared to the floor centrifuge is only a little smaller size and capacity. The development of universal desktop centrifuge has blurred the boundary of low speed, high speed, micro and large capacity centrifuge large capacity centrifuges.

Maintenance of centrifuges

(1) After each use, be sure to clean the centrifuge cavity and rotor.

(2) Clean up the water in the centrifuge chamber in time. Centrifuge operation using compression mechanism cold, because the air contains moisture, in the centrifuge cavity frost into water. Most large-capacity centrifuges have no drainage holes, and more water is accumulated in the centrifuge cavity. At this time, the rotor should be removed to clean up the water. When reinstalling the rotor, be sure to install it to avoid accidents.

(3) There are rubber sealing rings in the contact between the upper part of the centrifuge chamber and the door cover, and in the contact between the rotor seat and the bottom of the centrifuge chamber, and any deformation should be observed frequently to prevent external heat infiltration, such as deformation or aging should be replaced in time.

(4) Check regularly whether the door cover pneumatic support rod and door lock switch can work properly.

(5) Check regularly whether the cooling fan is working properly; regularly remove dust from the centrifuge ventilation window and condenser to ensure the ventilation effect and the heat transfer effect of the condenser.

(6) Check the oxidation layer on the inside and outside surface of the rotor regularly, if there is peeling, corrosion, serious scratch, deformation or crack, it should be stopped in use. When the centrifuge is not in use for a long time, the rotor should be taken out and coated with antirust oil on the rotor seat and drive shaft to prevent the rotor seat and drive shaft from rusting.