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.

The key points for screw conveyor selection

1.Conveyor capacity
Screw conveyor conveying capacity refers to the amount of material per unit time.Users should consider whether the conveyor can support the use of other production equipment before design in order to design a reasonable conveyor model.
2.Conveying speed
Conveying speed can improve the transmission capacity. For conveyor which adopts chain as traction, the transporting speed should not be too fast, in order to prevent the power load increasing .
3.Component dimensions
The component dimensions of conveyor includes conveyor trough width or pipe diameter , etc. Which directly affect the transmission capacity of screw conveyor.
4.Conveyor length and inclination
Conveyor length and inclination directly affects the total resistance and required power of the conveyor. Screw conveyors installation can be level and inclined, so please let us know the using condition when select the model.
5.Screw conveyor motors
Motor selection can be speed controlled motor or general motor to control the conveying speed and throughput per hour.
6.Others
Whether hopper should be considered in the inlet or not,as well as the feeding hopper size.  

Do you want a suitable screw conveyor?Check the required data for model selection.

Please see following data:
1. Material to be screened _______
2. Material size _______mm
3.Size distribution_______%?
4 .Water content  _______%?

5 .Capacity________t/h
6 .Material density ________t/m3?
7 .Material temperature _______ ℃?
8. Material is corrosive or not_______?
9. Distances between inlet and outlet ______m
10.Voltage __V__HZ 3 phase
11.Working environment _______

12.Special requirement:____

Above mentioned information is the basic one client need to offer which will save lots of time and money for model selection,further information please check: www.pkmachinery.com

Material Analysis before a Screw Conveyor is being used

The initial step in engineering a screw conveyor is to analyze the material being handled anf as certain its physical properties in order that they may be thoroughly evaluated and understood prior to proceeding with the conveyor sizing and selection. The properties of the materials are discussed in further depth below.

1.Lump Size

The minimum diameter of a conveyor screw for a given application is determined by the maximum lump size of the material being handled. It is necessary to thoroughly analyze the material and determine its maximum lump size and the percentage of lumps to total volume along with the minimum particle size and screen analysis when possible. 

2.Flowability

The flowability of a material will affects the horsepower requirement of the conveyor in question. Flowability is related to the angle of repose of a material. Fine free flowing materials can be handled at higher trough loadings with lower horsepower requirements than coarse, sluggish ones. 

3.Abrasiveness

The more abrasive the material being handled, the greater the wear the conveyor components are subjected to. Hence, it is necessary to determine the abrasive quality of the material in question prior to sizing the conveyor. Abrasiveness can be determined by knowing a material’s hardness. 

4.Moisture Content

Moisture content of materials is a factor that affects material flow. Excessively dry or wet products tend to flow easily. However, many develop sluggish characteristics when having moisture content between the two extremes. This is not accounted for in the material tables which follow and such materials should therefore be reclassified. 

What Factors that Affect the Screw Conveyor Conveying Efficiency ?

The factors are listed as follows:
1.The material has great viscosity and is easy to agglomerate. 
The viscous material is easy to stick on the screw blade and the inner wall of the screw conveyor, which will increase the resistance in the process of conveying, and directly affect the production efficiency.
2.The diameter size of the screw pipe.
Under the same conditions, conveying efficiency of the screw conveyor with larger diameter is higher than the conveyor with small diameter.

3.The dip angle and transportation distance of screw conveyor.
4.The particle size, temperature, moisture, abrasion and corrosion of the material.
Specific parameters can refer to: Screw conveyors and conveying technical parameters calculation formulas.
5.The rotate speed of the screw conveyor.
The rotating speed of the screw conveyor is related to the power of conveyor motor . The working speed of screw conveyor has a close relationship with the material characteristics. High speed screw conveyor requires strict assembly, and demands a better balance. 
Further information,please click:www.pkmachinery.com

What is impact of different materials on screw conveyor?

 Screw conveyor design depends on the parameters, however,these parameters depend on the required conveying material, thus, the screw conveyor engineer recommends will be a suitable equipment to convey materials, which can achieve the best possible conveying capacity.

Conveying capacity is one of the most important target to measure the production efficiency of screw conveyor. Generally speaking, the fast rotated speed of screw shaft can improve the production of conveyor.On the contrary, the low rotated speed will reduce the production. However, during the operation, the rotated speed should not be too high,otherwise material will be thrown outward due to the large centrifugal force, it will cause material cannot be conveyed, so the speed of the screw conveyor must be set in a certain value. 

Generally speaking, according to the material properties, materials can divided into four categories. The first category: material with good flow ability, lighter and non abrasion; The second category: material without abrasion,however the flow ability is worse; The third kinds of size scale and liquidity with second near the mill, but larger cut materials. The fourth class is illiquid and the fierce cut grinding material.

What Reasons Lead to Screw Conveyor Blade Damage

Damages may occur in the process of using screw conveyor,screw conveyor blade damage is the most common one. Here PK Machinery will discuss the screw conveyor wear in using process.
General wear parts include: hanging bearing, tail & end of the screw conveyor and screw blade,the reasons lead to wear is not only due to natural causes : temperature, environment and material, but also due to structure factor and human factor. Here, we will analyze what are the reasons leading to screw conveyor blade damage.

 

Generally speaking, screw conveyor is not easy to occur blocking phenomenon in the outlet, it can run at a low speed, reduce the energy consumption, design with a long conveying distance. However, when convey life garbage and organic plant, it may cause the damage of screw blade.
Thicker spiral blade will be anti- wear and durable, it is suitable for conveying materials, screw blade mainly wears in the blade edge.The farther the screw blade away from the axis of rotation, the larger the force it will bear and the more the cracks it will form.  

Application of Pickling Technology in Stainless Steel Screw Conveyor

Those days, our Philippine customer ordered stainless steel U type screw conveyors. Taking texture of material into consideration, we make a acid pickling and passivation fabrication processing to screw conveyor. Here PK Machinery will introduce you the application of pickling technology.
In the machining process of stainless steel, it will present scale cinder with black or yellow color. In order to improve appearance and stain resistance of stainless steel, it’s better to make a acid pickling and passivation fabrication treatment after processing it. Through this kind of technology processing, it can remove scale cinder which caused by weld or high-temperature processing and make it brighter. And it also can generate oxidation film that will prevent stainless steel from oxygen corrosion again so that can improve anti corrosion quality of stainless steel products and extend machine’s lifespan.

 

What is pickling technology? It is a way to clean metallic surface which adopts acid solution to remove scale cinder or corrosion sediments on stainless steel surface. Metallic surface will become silver-white color and be passivated after pickling. At the same, it can improve anti-corrosion capacity of stainless steel. At the present stage, it always takes long time to remove scale cinder by pickling and causes high processing cost. Taking this situation into consideration, users have better adopt quick pickling process in a normal temperature. This way can have a good influence on corrosion sediments and eliminate thick scale cinder quickly. Also, it can make metallic surface brighter and undefiled after pickling. What’s more, metallic surface will be not easy to have gloss loss, color fading or yellow discolouration. 

Stainless Steel Screw Conveyor Used for Gelatin was Delivered to Philippines

Last week, stainless steel screw conveyors which are designed for gelatin left PK factory and was delivered from Qingdao Harbor to the destination of Manila South Harbor.
The screw conveyors are ordered by Philippines clients, the lengths from inlet to outlet are 6m and 3m, considering the conveying material “gelatin” is used for food processing and production line, engineer suggests using stainless steel U type screw conveyor with the model of LS250.

After the completion of installation and trial run, there is also a pickling & passivation processing which can not only remove all kinds of oil, rust, oxide skin weld spot, but also improve the corrosion resistance performance of stainless steel greatly.
More information please click: www.pkmachinery.com  

Screw Conveyor Spare Part:Screw blade,reducer,flange,tail stock,hanging bearing

Description

The spare parts of Screw conveyor include:cardan joint,hanging bearing,tail stock,flange,reducer,screw blade etc. In order to let you know better of this,we will show the technical data which will make you easy to choose

Technical data Screw blade

Outer Dia. (mm)	Inner Dia. (mm)	Screw Pitch (mm)	Plate Thickness (mm）
140	60	140	3.5
140	60	110	3.5
140	60	140	5
140	60	110	5
190	(60) (73)	200	3.5
190	(60) (73)	133	3.5
190	(60) (73)	200	5
190	(60) (73)	133	5
240	(60) (73)	240	5
240	(60) (73)	166	5
290	(89) (114)	300	5
290	(89) (114)	220	5
220	140	180	5
292	114	300	7.2
292	114	220	7.2

► Brief introductionSpare parts of cement screw conveyor include screw blade, reducer, intermediate bearing (hanging type), Tailstock, flange plate, cardan joint etc.

                                  Universal joint                                         Intermediate Bearing

                                    Tailstock                                                  Reducer

Further information please click: www.pkmachinery.com