How to calculate the transmission capacity of the screw conveyor?

1, the density of material and property of the material

2, the selection of the screw conveyor model size and delivery distance, the installation direction, etc..

Approximate calculation formula of screw conveyor:

Capacity Q = 47 D2 N TΦP C（t/h）

Formula:

Q - transport capacity (t/h);

D - conveyor diameter m;

N-- screw shaft speed r/min;

T - pitch m;

Φ - material filling coefficient, under normal circumstances, the grain by =0.25 - 0.4, =0.25 - 0.35 psi oil, wheat bran, rice bran flourψ=0.25, ψ =0.2

P - bulk density  t/m3;

C - conveyor angle coefficient;

S - helical blade pitch (m), S=0.8D of the face, with a blade of S=D.

Calculation formula for ultimate speed:

Formula: N /min - helical axis limit rotational speed (Y);

A - the coefficient of the material properties, the general desirability of grain and oil materials is A=65.

Installation notice of circular vibrating screen punching mesh

General screen meshes include manganese steel woven wire mesh, punching mesh and stainless steel screen plate etc. Each kind mesh should be selected according to the on-site working condition. Today we will talk about the installation of punching screen mesh.
The punching screen mesh installation method for circular vibrating screen is the same with dewatering screen.
Generally speaking, the slurry dewatering screen is horizontally installed,however, in order to guarantee the application effect, the screen mesh is installed with a negative angle. The screen mesh can be polyurethane material with tension type installation, or stainless steel bar screen mesh with compression type to meet different working conditions.

Circular vibrating screen is installed with angle, when adopt the punching screen mesh, it needs lumps of wood to press tightly, then tension with wood key . Please see the following sketch: 
If the screen mesh tension is not enough, it will bring negative influence:
1.The screen mesh is easy to bend and the screen mesh will slack and easy to revibrate. Meanwhile it will reduce the screen mesh service life. 
2.It will influence the effective screen surface, reduce the screening efficiency.
3.It will stop the material moving forward and reduce the capacity.
In this regard,in order to guarantee the smooth screen mesh , increase the service life and guarantee the capacity and screening efficiency, the tension of screen mesh must be improved. 

Further information please click: http://www.pkmachinery.com/faq/installation-circular-vibrating-screen-punching-mesh.html 

Reason Analysis for Rubber Falling Off the Belt Conveyor Pulley

Rubber falling off the pulley is one of the common trouble of belt conveyor,after many years of practice and analysis, the reasons are as following:
1.The wrapping angle between pulley and belt is too small.
Peripheral force of driving pulley is transmitted to belt by friction.In running,in order to avoid slipping between pulley and belt,the belt tension is not allowed too big.According to Euler’s Formula,if the wrapping angle is smaller,the belt tension will be bigger,so it’s easy to slip.Slipping will speed up the wear of pulley.
2.Water or wet material stick on the belt surface.
When transporting material contents dust,like coal,ore and so on ,we usually use water spray to remove dust,thus water will be mixed with material and stick on belt surface,besides,rain will also lead water sticking on belt, once water sticks on belt surface,the friction coefficient between belt and pulley will decline which will cause slipping between belt and pulley,and speed up the wear of pulley.

3.The tension is too small.
Tension device is very important to conveyor pulley,if the tension is too small,it will lead to slip,causing wear of pulley,when the tension distance is not enough and the belt with permanent deformation,we can cut a segment of belt,then vulcanize again.
4.The failure of cleanser.
The failure of cleanser can result in the adhesive materials entering into belt and pulley,causing wear between belt and pulley, thus the rubber cover will fall off the pulley,and reduce the service life of belt.
5.Belt conveyor material scattering .
Belt conveyor material scattering is a common problem,when the material scatter during machine running,a portion of material will enter into belt and pulley,which will cause the wear of rubber surface and belt.

Solution to trommel screen mesh blockage of Kazakhstan customer

Our Kazakhstan customer told us that the trommel screen he purchased two months ago occurred blockage during the operation process which makes the screening efficiency very poor. After communication,we found out the blockage was caused by the high humidity material, here engineers gives some solutions accordingly to prevent blockage:

1.Add an automatic cleaning brush on screen which can achieve automatic cleaning during operation. 

2.Add an air compressors, since sand is slightly damp, so cleaning purpose can be achieved by air force.

3. Add an anti blocking device, due to the high frequency and small force of vibration impact, it can clean up the blockage efficiently.

In addition, textile screen mesh made of 16Mn can also adopted to ensure material pass through the mesh smoothly.

Hope above methods is helpful,further information please click: www.pkmachinery.com 

What's the Special Role of Vibrating Screen Bouncing Ball?

When the vibrating screen works, have you ever noticed that the bouncing balls beat up and down on the sieve mesh? Why this phenomenon occurs on the sieve mesh? What's special role of bouncing ball? Today we will take a brief look.
These bouncing balls are an essential part of vibrating screening machines.Its role is beating the sieve mesh up and down avoid adhesion material blocking the sieve mesh which can improve screening efficiency and accuracy.

Bouncing balls are generally divided into different diameters: φ10, φ15, φ20, φ25, φ28, φ30, φ40, φ50, φ60 and so on, commonly used ones are φ25 and φ28 , φ40, φ50and φ60 mainly used for mine vibrating screen.
According to the material,bouncing ball can be classified into several types: rubber ball, silicone ball, PTFE ball bouncing, according to different materials of bouncing balls, the application and function is also different.
Natural rubber bouncing ball：it is suitable for general material screening process;
Silicone bouncing ball：good elasticity., mainly used for food, medicine and other materials screening;
PTFE bouncing ball : It can soak in the oil , mainly applied to oily liquid materials screening.
The bouncing balls should be selected based on different material properties to meet customer requirements in different conditions. Though bouncing ball is a small accessory, it is the key to solve the problem of screening.