ICUE 2018 on Green Energy for Sustainable Development Thavorn … · 2018-10-22 · A. Hammer mill machine A hammer mill machine is the most common used for crushing equipment especially

ICUE 2018 on Green Energy for Sustainable Development Thavorn Palm Beach Resort Karon, Phuket, Thailand. 24 – 26 October 2018

Design and Analysis of a Hammer Mill Machine in High-Efficacy Recycle Process

Arpha Armatmontree and Wimol San-Um Engineering of Technology

Thai-Nichi Institute of Technology Bangkok, Thailand

[email protected]; [email protected]

Chadaporn Keatmanee

Digital Engineering Thai-Nichi Institute of Technology

Bangkok, Thailand [email protected]

Abstract—This paper proposes a three-dimensional model of the hammer mill for high-efficacy recycle process. It has been established with modeling software (SolidWorks) to solve the inconvenience of the testing with a real machine by imported into Simulink. According to various types of wastes creating in huge amounts by every consumption around the word, an effective hammer mill machine is strongly required. The machine should be able to mill all types of wastes including soft (food waste) and hard materials (construction and demolition waste). The significant factors of the modeling of a hammer mill machine are relied on its blades. Therefore, we introduce the calculation of force applying to the blades, as well as, the evaluation of materials are used for making the blades (Stainless steel and Titanium). The evaluation of the force according to the blade materials are conducted by the simulation of the hammer mill model used for corn and brisk. The experimental results show that the proposed force applying to the blades made of Titanium are able to mill both of corn and brisk more efficiently than stainless steel blades do considering to the following parameters: normal stress, static stain, static displacement, and factor of safety (FOS).

Index Terms—hammer mill machine, recycle process, stainless steel blades, SolidWorks, Titanium blades, waste management system.

I. INTRODUCTION Waste management (WM) has been investigating

intensively since many decades around the world [1], [2]. The fundamental problems lie in the inability of traditional WM practices to handle with and adapt to the massive increases in volume and change in composition of waste streams in which non-biodegradable consumer packaging, food waste, e-waste, as well as, construction and demolition waste [3]. The waste can be transformed in to both reused and non reused process. The use of human labor in the process may not be suitable such as lack of security. Automatic process is an interesting option in recycle process of WM process. Crushing machine is also one of the necessary machines in WM process for milling various types of wastes including soft and hard material. Therefore, this study focuses on designing a 3D model of a hammer mill machine [4], [5]. In addition, we also analyze the hammer mill machine’s blades made from different materials including Stainless steel and Titanium to

find the most suitable one in order to crush several kinds of waste.

A. Hammer mill machine A hammer mill machine is the most common used for

crushing equipment especially in waste management system. Moreover, it is high production capacity, uniform product, low energy consumption, reliable quality, simple structure, as well as, easy maintenance. In working principle of a hammer mill machine shown in Fig. 1, a motor drives the rotor quickly for the crushing cavity. The tested materials including soft and hard particles enter the crusher through the feeding and are impacted, cut, and grounded by high-speed hammer heads. There is a grate under the rotor assembly, hence materials with size smaller than the grate mesh will be screened out and others are left to be further hammered until they reach standard sized (1-3 mm). The size of the final product can be adjusted by changing the grate (the gap between the rotor assembly). In addition, the grate can also be adjusted according to different needs.

Figure 1. A hammer mill machine used for grinding and crushing several materials. [6]

B. The materials of the blades 1) Stainless steel: is a useful material because it is widely

beneficial for engineering design [7]. Stainless steel is also a popular class of material for blades because it resists corrosion and it is easy to maintain. However, it is not impervious to rust or corrosion. We evaluate the performance of Stainless steel blades by simulating Stainless3370N and 9631N for their compacting to soft and hard material.

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2) Titanium: can be fused with other elements to produce

strong, lightweight alloys for aerospace, military process, automotive, industrial process, as well, as making blades for crushing machine [8]. Titanium numbered 3770N and 9631N are utilized for these experiments.

II. THE 3D MODEL OF A HAMMER MILL MACHINE Modeling of mechanical components and systems has

often done with CAD tools [10], [11]. These softwares are useful for specifying the details of three dimensional (3D) components in mechanical systems. Once the CAD model is completed, engineers need to design a control system for it. After that the analysis of the effect between the models components and the performance of the overall system is needed. We use SolidWorks simulation packages for a hammer mill machine by translating a CAD file into an environment where control design of its blades can be achieved. The figures of hammer mill machine in 3D are shown in Fig. 2 to 4.

III. THE CALCULATION OF FORCE APPLYING TO THE BLADES OF A HAMMER MILL MODEL

The hammer mill machine uses a motor to drive the rotor for crushing particles through the feeding. In this modeling, the power of motor is fixed, as well as, the adjustment of the grate. This paper focuses on finding a suitable material for the blades which can crush various types of wasts including soft and hard. The durable and wildly used materials, Stainless steel and Titanium are evaluated on corn as food wasted and brick as construction and demolition waste. All fixed parameters are;

• Motor power: P =7.5 KW

• Design speed: N =400 rpm

• Blades radius: R =0.16 m

• Blades mass: m =1.4 kg

• Support hight h =0.0875 m.

First, the force that applies to the blades has to be calculated. Considering to Fig. 5 and Fig. 6, normal force (Fn) and tangential force (Ft) are calculated as following equations;

(1) v = ω · R (2)

(3) and Ft = σc · A (4)

Where σc is compressive stress or shear stress (σc = 50 kg/cm2, A is cross section area (A =19.63 cm2).

Whereas, the reaction forces are;

Rt = Ft (5)

Rn = Fn. (6) From Eq. 4 to 6, the normal forces for both corn and brick

is Fn =393 N. Whereas, tangential force for corn and brick are Ft =3770 N, and 963 N respectively.

IV. THE EXPERIMENTAL RESULTS Due to the various types of wastes around the word, an

effective crush machine is needed. The machine should be able to crush all types of wastes including soft (corn) and hard particles (brick). The key factors of a hammer mill machine are relied on the materials of its blades. Therefore, we conduct the experiments based on the materials used for making a hammer mill machine’s blades including Stainless steel and Titanium. Referring to the calculation in Section III, fixed value of hammer mill motor power was 7.5 kW; chosen materials for testing are Titanium and Stainless steel; the calculated values of the brick, Normal force Fn was 393 N and Tangential force Ft was 9631 N; the calculated value of the corn, Fn was 393 N and Ft was 3770 N.

The results of the chosen material evaluation are explained as follows.

A. Soft material testing: Corn as Food waste Stainless steel blade is used for compacting the corn (the

resistance of the material before breaking or separation). The values of the Simulation program from SolidWorks show that;

– Normal stress: it is a stress occurs when a member is loaded by an axial force. The value of the normal force (Fn) in any prismatic section is the force divided by the cross sectional area. The maximum blade yield was 229.65 Mpa, which was higher than the yield strength of 172.34 Mpa.

– Static strain – Static displacement: the highest expansion value is

0.146 mm, which is very small. – Factor of safety (FOS): the lowest value was 0.75.

• Titanium blade the simulated values are; – Normal stress: the maximum blade yield was

227.21 Mpa, which was higher than the yield strength of 744.63 Mpa.



In conclusion, to design a hammer mill to compact corn plants. Using a Titanium blade is more suitable than Stainless steel because it has a higher hardness than the maximum force and has a minimum safety rating of 3,277. If using a stainless steel blade, it must be strengthened to the force. The maximum force is greater than the strength of the material and has a minimum safety value of 0.75. The comparison of Stainless steel and Titanium blades are shown in graphs in Fig. 7.


B. Hard material testing: Brick as construction and demolition waste

• Stainless steel blade is used for compacting the brick. The values of the Simulation program from SolidWorks show that;

– Normal stress: the maximum blade yield was 606.912 Mpa, which was higher than the yield strength of 172.339 Mpa.



• Titanium blade the simulated values are; – Normal stress: the maximum blade yield was

576.901 Mpa, which was less than the yield strength of 744.634 Mpa.

– Static strain – Static displacement: the highest expansion value is – 0.68 mm, which is very small. – Factor of safety (FOS): the lowest value was 1.29.

In conclusion, to design a hammer mill to compact bricks. The Titanium blade is good because it has a higher hardness

than the maximum force and has a minimum safety rating of 1.29.

However, it cannot be used with stainless steel because it has a lower strength. In the case of maximum force, it will damage the blade. The comparison of Stainless steel and Titanium blades are shown in graphs in Fig. 8.

V. CONCLUSION AND FUTURE WORK Due to the massive increases of waste management (WM)

system to handle with huge amount of various kinds of waste in waste management process, an effective crushing machine is strongly needed. Therefore, we introduce the design and analysis of the three dimensional hammer milling machine specifying to material of its blades. There are two widely used materials have been investigated including Stainless steel and Titanium. From a number of experiments according to four analyzing parameters; normal stress, static stain, static displacement, and factor of safety, the Titanium blades performs compacting to both corn and brick better than Stainless steel blades do. Therefore, the blades made from Titanium is the most suitable material for crushing various types of waste in WM system. In the future work, we plan to build a real hammer mill machine following the proposed 3D model.

Figure 2. The detail of 3D components for a hammer mill model.


Figure 3. The detail of 3D components for a hammer mill model (continue).

Figure 4. The detail of 3D components for a hammer mill model (continue).


Figure 5. Diagram of force calculation for a hammer mill machine.

Figure 6. Vector of normal and tangential force (Fn and Ft) apply to a hammer mill machine’s blades.

(a) Normal stress

(b) Displacement

(c) Factor of safety (FOS)

Figure 7. Graphs show the comparison of Stainless steel (orange line) and Titanium (blue line) blades compacting to corn.


(a) Normal stress

(b) Static displacement

(c) Factory of safety (FOS) Figure 8. Graphs show the comparison of Stainless steel (orange line) and

Titanium (blue line) blades compacting to brick.

REFERENCES

[1] P.Yadav and S.R. Samadder, “A critical review of the life cycle assessment studies on solid waste management in asian countries,” Journal of Cleaner Production, vol. 185, pp. 492 – 515, 2018.

[2] S. A. Bassi, T. H. Christensen, and A. Damgaard, “Environmental performance of household waste management in europe - an example of 7 countries,” Waste Management, vol. 69, pp. 545 – 557, 2017.

[3] G. MacRae and L. Rodic, “The weak link in waste management in tropical asia? Solid waste collection in bali,” Habitat International, vol. 50, pp. 310 – 316, 2015.

[4] S.-J. Shin, J. Woo, and S. Rachuri, “Energy efficiency of milling machining: Component modeling and online optimiza tion of cutting

parameters,” Journal of Cleaner Production, vol. 161, pp. 12 – 29, 2017.

[5] M. Bal, “Ball milling of eggshell waste as a green and sustainable approach: A review,” Advances in Colloid and Interface Science, pp. –, 2018.

[6] Hammer mill machine @ONLINE, “Hammer crusher,” http://www. baichy.com/Crushing/Hammer.html, 2018.

[7] J.R. Davis and A.S.M.I.H. Committee, Stainless Steels, ASM specialty handbook. ASM International, 1994.

[8] C. Leyens and M. Peters, Titanium and Titanium Alloys: Fundamentals and Applications, Wiley, 2006.

[9] S. Jian-guo and X. Ping-ping, “Simulation of car driving based on solidworks and simulink,” in 2011 International Conference on Electric Information and Control Engineering, April 2011, pp. 5310–5313.

[10] G. Fois, A. Floris, A. Serpi, M. Porru, and A. Damiano, “Design criteria for ferrite-based high-speed permanent magnet synchronous machines,” in 2017 7th International Electric Drives Production Conference (EDPC), Dec 2017, pp. 1–7.

ICUE 2018 on Green Energy for Sustainable Development Thavorn … · 2018-10-22 · A. Hammer mill machine A hammer mill machine is the most common used for crushing equipment especially

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