14768841 Vibrating Screens

University of Cairo Faculty of Engineering Chemical Engineering Department

Vibrating Screens

April, 2009

University of Cairo Faculty of Engineering Chemical Engineering Department

Vibrating Screens

Submitted to:

Dr. Ahmed Sherif Eissa Chemical Engineering Department Faculty of Engineering, University of Cairo

Prepared by: Group 16 Sec: 4 Marwan Sallam Marwa Samir Marwa Adel Marwa Mahmoud Ahmed Mostafa Ahmed Saad Mostafa Mohsen Rafeek Mostafa Mohammed Maghawry Moataz Said Eissa Moataz Mohammed Atef Moataz Nabil Elsayed April 29th, 2008

B.N.: 1 2 3 4 5 6 7 8 9 10

Table of Contents Abstract

II

List of Figures and Tables

III

1. Introduction

1

2. Basic Principles and Theory of Operation

1

3. Advantages of Vibrating Screens

1

4. Equipment Details

2

4.1 Illustrated Figures

2

4.2 Description

3

4.3 Equipment Photos

4

4.4 Material of construction

5

5. Equipment Design

5

5.1 Design equations

5

5.2 Commercially Available Designs

5

6. Manufacturers

6

7. Cost Estimation

7

7.1 Using Cost Charts

7

7.2 Factors affecting the cost of vibrating screen

8

Summary

8

References

9

I

Abstract The vibrating screen is a type of sieving equipment used in grading and separating materials into various sizes to be used in different fields such as minerals and building materials. This report includes the technical description of the vibrating screen. It discusses the basic principles and theory of operation of the vibrating screen, detailed description of the equipment and the equations governing the variables of vibrating screen showing all the mechanical parts of the vibrating screen. It also discusses the approximate cost of the vibrating screen and it shows some of the famous manufacturers of the equipment.

II

List of Figures

Figure 1:

Side elevation as embodied in an inclined vibrating screen

2

Figure 2 :

End elevation of the separator

2

Figure 3 :

Three pictures showing vibrating screen

4

Figure 4 :

Chart of Cost vs. Screen area with material adjustment factors

7

III

List of Tables

Table 1:

Parts name of the vibrating screens

4

Table 2:

Standarized designs of vibrating screens

5

Table 3:

List of famous manufacturers

6

Table 4:

Chemical engineering plant cost index

7

Table 5:

Annual index

7

Table 6:

Cost table of custom material of construction

8

IV

1. Introduction The vibrating screen is a type of sieving equipment used to separate materials into various sizes for further processing, or far end use, depending on your need. They are mainly used for grading and screening materials in the following fields: coal dressing, metallurgy, mines, building materials, transportation, chemical industries, smelting and many other fields. The material is separated by passing it through a vibrating screen box which has a number of different sized screens, or meshes, which the material falls through like a sieve. The material falls onto attached conveyors which stock pile the end product. The end products can then be used in the building and construction industries.

2. Basic Principles and Theory of Operation The vibrating screen consists of screen box, supporting device, vibration exciter, transmission part, etc. The barrel-type vibration exciter is installed in the middle part of the machine. During normal operation, the vibration of exciter will drive the screen mesh fixed on the screen box vibrate, and then materials will be screened. The big and small materials fall from the upper side and lower side of the screen to get them separated [1]. Amplitude or stroke adjustment provides vertical motion and the material which being screened loses some of its particles that depends on size and nature of these particles. Frequency or speed adjustment is directly related to a lower stroke with high speed or to a greater stroke with low speed. The slope of the screen governs the speed of the material flow Also direction of rotation controls the direction of flow. Maximum separation efficiency and high capacity production are reached if proper rotation is selected [1].

3. Advantages of Vibrating Screens 1. Simple and dependable Eccentric type system. 2. High screening capacity. 3. High durability. 4. No transmission of screen panels. 5. Ready changing of screen plates. 6. Rigid and vibrating resistance screen body.

1

4. Equipment Details 4.1 Illustrated Figures

Figure 1: Side elevation as embodied in an inclined vibrating screen [2].

Figure 2: End elevation of the separator[2].

2

4.2 Description: A conventionally constructer rectangular separator screen 1, figs 1 and 2 is held between the parallel side walls 2 of an upper vibrating frame 3. The screen proper is secured within the frame 3 by multiple turnbuckle means 4 accessible at the two side of the frame 3. The vibration frame 3 is inclined, as shown, and is equipped at its upper end with a material input chute 5, the lower discharge end of the frame 3 being indicated by the numeral 6. The space 7 beneath the screen separator is unobstructed so that a conveyor or other collector means an occupy this space and receive material passing through the vibrating screen. The upper frame 3 carries depending divergent legs 8 resting on coil spring vibration support 9, in turn mounted on a relatively stationary base frame or bed 10, as illustrated. in this manner, the vibration frame 3 with its separator screen 1 is bodily and floatingly supported on the spring means 9 for vibratory motion. The vibration motor means comprise a pair of counter-rotating conventional vibration motors 11 mounted on the exterior of the opposite side walls 2 of vibration frame 3. By virtue of this external side mounting ,the two motors 11 are immediately accessible for adjustment , repair or replacement .Each motor 11 is attached by a suitable fastener means at 12 to a motor mounting plate 13 having apertured end extensions 14. A coacting two-part motor mount 15 for each vibrating motor 11 consists of a center disc 16 having an annular marginal step groove 17. Surrounding the disc 16 in spaced concentration relation therto is an L-cross sections ring 18. The disc 16 and ring 18 are preferably welded to adjacent side wall 2. An annular T-cross section passage 20 is created between the two elements 16 and 18 for the reception of T-bolts 21, whose shanks are received through aperture 22 in extensions 14. The T-bolt shanks can travel in either direction through annular passage 20 when their locking nuts 23 are released. The locking nuts 23 for T-bolts 21 engage the exterior face of plate 11. By loosening the nuts 23 slightly, each vibration motor 11 can be bodily and rotationally adjusted relative to the side wall 2 through a full 360 degrees in a plane parallel to the side wall 2 and parallel to the axis of the motor armature shaft. Each vibration motor can be securely locked in any selected adjusted position by tightening the nuts 23. The rotational adjustment of each motor 11 around the circumference of the ring 18 changes the angle of the motor armature of the rotation axis [2].

3

No.

Part name

No.

1

Rectangular separator screen

9

2

Parallel side walls.

10

3

Vibration frame

4

Part name

No.

Part name

Spring means

17

Annular marginal step groove

18

Rings

11

Relatively stationary base frame or bed Motor

19

Circular cap

Turnbuckle means

12

Motor mounting plate

20

5

Chute

13

21

6

Numeral

14

22

Aperture

7

The space

15

Apertured end extension Coacting two-part motor mount Center disc

Annular T-cross section passage T-bolts

23

Nuts

8

Divergent legs

16

24

The floor

Annular marginal step groove

Table 1: Parts name of the vibrating screens [2].

4.3 Equipment Photos

Figure 3: Three pictures showing vibrating screens [3]. 4

4.4 Material of construction Screens may simply consist of parallel metal bars but more often they will take the form of a perforated metal plate, woven wire cloth or fabric (such as silk). Commonly used metals are steel, stainless steel, copper, etc…

5. Equipment Design Design of vibrating screens depend on three major factors which are mesh sizes, aperture and open area. The factors can be estimated by determining the flow rate and its properties such as screen analysis of the feed and the desired product. Design parameters can be divided into basic and tables of commercially available models.

5.1 Design equations F= D+B

F.Xf = D.XD + B.XB E

E

D/F = (Xf-XB) / (XD-XB)

B/F = (XD-XF) / (XD-XB)

D. XD. B1 XB F. XF. F1 XF

Xf XB XD XF 1 XB. XD XD XB 2 1 XF. XF

5.2 Commercially Available Designs: Model 2YZS1237 3YZS1237 2YZS1548 3YZS1548 2YZS1848 3YZS1848 4YZS1848 2YZS1860 3YZS1860 4YZS1860 2YZS2160 3YZS2160 4YZS2160 2YZS2460 3YZS2460 4YZS2460

Handling Motor Screen Max. power mesh feed size capacity (mm) (t/h) (kW) (mm) 2 3-100 400 10-80 11 3 3-100 400 10-80 11 2 3-100 400 30-200 15 3 3-100 400 30-200 15 2 3-100 400 50-250 18.5 3 3-100 400 50-250 18.5 4 3-100 400 50-250 18.5 2 3-100 400 65-586 22 3 3-100 400 65-586 22 4 3-100 400 65-586 30 2 3-100 400 81-720 22 3 3-100 400 81-720 30 4 3-100 400 81-720 30 2 3-150 400 100-810 30 3 3-150 400 100-810 37 4 3-150 400 100-810 37 Table 2: Standarized designs of vibrating screens[4].

Screen size No. of (mm) Layer 3700×1200 3700×1200 4800×1500 4800×1500 4800×1800 4800×1800 4800×1800 6000×1800 6000×1800 6000×1800 6000×2100 6000×2100 6000×2100 6000×2400 6000×2400 6000×2400

5

Vibrating frequency (r/min) 750-950 750-950 750-950 750-950 750-950 750-950 750-950 750-950 750-950 750-950 700-900 700-900 700-900 700-900 700-900 700-900

Double swing (mm) 5-9 5-9 5-9 5-9 5-9 5-9 5-9 5-9 5-9 5-9 5-9 5-9 5-9 5-9 5-9 5-9

Nomenclature If we take the model 2YZS1237 for example, 2 Y

Number of layers. The letter refers to the circular motion.

ZS They are specific for each company i.e. these letters are for Henan Liming Road & Bridge Heavy Industry Co., while they are replaced by 'K' in Shanghai Zenith Electric Power Equipment Co., so it differs from one company to another. 1237 Stands for the screen dimensions, mm = (1200x3700) and so on for the other models.

6. Manufacturers Anping Kaibo machinery limited co., China

Seller-Manufacturer

China NanChang ChangJiang Minning machinery co., China

Seller-Manufacturer

Anping Yuzhihao Wiremesh products factory, China

Seller-Manufacturer

Shanghai Shibang machinery co. LTD, China

Seller-Manufacturer

Shanghai Zenith co., China

Seller-Manufacturer

Hongchdaoda co., China

Seller-Manufacturer

Zhengzhou Yifan machinery cooperation LTD, China

Seller-Manufacturer

Henan Liming Road and Bridge Heavy Industry Co., China

Seller-Manufacturer

Shanghai Zenith Power Equipment co., China

Seller-Manufacturer

Lutai International Trade Department, China

Seller-Manufacturer

Henan Dahua Minning machinery co. LTD, China

Seller-Manufacturer

Yusheng company, China

Seller-Manufacturer

Rotex, Inc., Ohio , US

Manufacturer

Triple/s Dynamics, Texas, US

Manufacturer

Won Duck Industrial Machinerty Co., Ltd, South Korea

Seller-Manufacturer

Foladsaza-e Almanabad Co, ltd, Iran

Seller-Manufacturer

VIBRA Maschinenfabrik Schultheis GmbH & Co. KG, Germany

Seller-Manufacturer

KG Mogensen GmbH & Co, germany

Manufacturer

Pioneer Weld and Weaves Pvt Ltd, India

Seller-Manufacturer

Table 3: list of famous manufacturers[5],[6],[10],[11],[12].

6

7. Cost Estimation 7.1 Using cost charts

Figure 4: Chart of Cost vs. Screen area with material adjustment factors [7].

(1957-59 = 100)

Jan. ’09

Dec. ’08

Jan. ’08

Equipment

Prelim. 642.4

Final 654.3

Final 632.7

Table 4: Chemical engineering equipment cost index [9].

Annual Index 2001 = 394.3 2002 = 395.6 2003 = 402.0 2004 = 444.2 2005 = 468.2 2006 = 499.6 2007 = 525.4 2008 = 575.4 Table 5: Annual index [9].

7

7.2 Factors affecting the cost of vibrating screen 1- Capacity, where bigger ton per hour needed equal bigger wider screen box needed, bigger shafts, bigger bearings, bigger slide plates, more steel to build and more safety factor. 2- Type of screen. (single, double, triple deck), where bigger vibrating screen require more engineering knowledge to create structure. 3- Material of construction. 4- Deck area. 5- Horizontal or flat screens are generally costly to buy, more costly to run and more costly to maintain. Price 18700$ 20600$ 23200$ 33200$ 19900$ 18800$

Material of cloth wire Medium carbon steel wire Medium carbon steel wire Medium carbon steel wire Medium carbon steel wire Medium carbon steel wire Heavy carbon steel wire

Material of construction Carbon steel Carbon steel Stainless steel Nickel alloy Carbon steel Carbon steel

Deck area 32 ft2 32 ft2 32 ft2 32 ft2 50 ft2 32 ft2

Screen type 1- deck medium 3- deck 1- deck medium 1- deck medium 1- deck medium 1- deck medium

Table 6: Cost table of custom material of construction [8].

Summary The vibrating screen is a type of sieving equipment of high capacity and high efficiency. It adjusts the amplitude by tube-shaped violent vibration screen of eccentric shaft and eccentric blocks. The body moves like a circle, in order to make the materials screened. It is widely used for grading and screening materials in the following fields: minerals, mines, building materials, water conservancy and hydropower, transportation, chemical industry, smelting and many other fields. It features long flowing line, many screening specifications, strong violent vibration force, high screening efficiency, small vibrating noises, firm and durable construction, convenient maintenance and safe operation.

8

References

[1]

http://www.break-day.com/en/vibrating-screen.html, cited in December 2008

[2]

United States Patent No. 4274953 , June 23rd, 1981

[3]

Shangahai Shibang Machinery Co., Ltd, http://www.sbmchina.com

[4]

Henan Liming Road & Bridge Heavy Industry Co., Ltd, http://www.vibratingscreen.cn

[5]

http://www.tradeegypt.com, cited in December 2008

[6]

[10]

William D. Robinson, The Solid Waste Handbook, 1986, Pg460 Max S. Peters, PLANT DESIGN AND ECONOMICS FOR CHEMICAL ENGINEERS 5Ed., 2002, Pg865 http://www.matche.com, cited in December 2008 http://www.che.com/business_and_economics/economic_indicators.html/,cited in April 2009 http://www.laxmi-group.com,cited in April 2009

[11]

http://www.industrystock.com, cited in April 2009

[12]

http://www.made-in-china.com, Cited in April 2009

[7] [8] [9]

9