Научная статья на тему 'RELIABILITY MODELING OF A BUTTER CHURNER AND CONTINUOUS BUTTER MAKING PRODUCTION SYSTEM'

RELIABILITY MODELING OF A BUTTER CHURNER AND CONTINUOUS BUTTER MAKING PRODUCTION SYSTEM Текст научной статьи по специальности «Медицинские технологии»

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Butter churner / continuous butter making / seasons / semi-Markov process / profit

Аннотация научной статьи по медицинским технологиям, автор научной работы — Upasana Sharma, Drishti

In the dairy plant, an investigation into the machine that makes butter was subjected to a reliability study in relation to the seasonal demand. In the process of expanding the butter churner into a machine that can make butter continuously, a more reliable operational model was devised. Both the models and the data acquired with MATLAB have been subjected to availability and reliability testing and analysis. In addition, the graphical analysis was carried out with the help of Code Blocks and Excel. A comparison of the two models was then covered as the final topic. It was discovered that (a) the extended model was superior to the current model, (b) the failure rate of the existing line increased, which implies that a new machine needs to be added to the line to share the load, which results in improved production, and (c) the failure rate of the extended model was lower than the failure rate of the existing model. (c) in order to maximise profits while simultaneously minimising losses The effectiveness of the system ought to be enhanced by performing routine maintenance during both the summer and the winter.

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Текст научной работы на тему «RELIABILITY MODELING OF A BUTTER CHURNER AND CONTINUOUS BUTTER MAKING PRODUCTION SYSTEM»

RELIABILITY MODELING OF A BUTTER CHURNER AND CONTINUOUS BUTTER MAKING PRODUCTION SYSTEM

Upasana Sharma1 and Drishti 2*

1,2Department Statistics, Punjabi University, Patiala- 147002, India usharma@pbi.ac.in, drish2796@gmail.com

Abstract

In the dairy plant, an investigation into the machine that makes butter was subjected to a reliability study in relation to the seasonal demand. In the process of expanding the butter churner into a machine that can make butter continuously, a more reliable operational model was devised. Both the models and the data acquired with MATLAB have been subjected to availability and reliability testing and analysis. In addition, the graphical analysis was carried out with the help of Code Blocks and Excel. A comparison of the two models was then covered as the final topic. It was discovered that (a) the extended model was superior to the current model, (b) the failure rate of the existing line increased, which implies that a new machine needs to be added to the line to share the load, which results in improved production, and (c) the failure rate of the extended model was lower than the failure rate of the existing model. (c) in order to maximise profits while simultaneously minimising losses The effectiveness of the system ought to be enhanced by performing routine maintenance during both the summer and the winter.

Keywords: Butter churner, continuous butter making, seasons, semi-Markov process, profit.

1. Introduction

As a result of high levels of "lifetime" engineering uncertainty, reliability engineering deals with predicting, preventing, and managing engineering failures. Costs of failures caused by equipment failure, parts costs, repairs, and personnel costs are all taken into account when reliability engineering is conducted. Industry engineers now put their effort on efficiency and high quality production. This can be achieved by improving system performance. When it comes to industrial applications on food production lines, ensuring a high level of reliability is highly important; however, reliability itself can be complex, many interconnected variables must be taken into account when guiding and assessing various levels of reliability.

Using maintenance regimes [9] processed site performance improvement in the dairy industry. [8] presented a case study on optimised performance of butter oil production. Based on real data [5] represented generation of wind power and electric power demand. Reliability analysis where operation is effected by temperature conditions was given by [2] and [1]. RAM analysis for modeling complex engineering systems was used by [6].

Introducing redundancy into a system can enhance its reliability. Redundancy with standby (redundant) units refers to the usage of additional units with the primary unit of the system, with the additional unit(s) becoming operational and performing all the desired functions with equivalent parameters upon the failure of the primary unit. Standby redundancy technique was used by several researchers to enchance system performance namely [3], [4], [7] etc. Work on standby units in a dairy industry was done by [10], [11] and [12]. Description of the systems

In model 1, the system which we have considered consists of a churner that works in both the seasons i.e., summer and winter. In winters, due to high demand system is always operating

unless a failure occurs that can be due to electricity hault or any fault in the churner. In summers, due to less demand the system sometimes goes to cold standby state when there is no demand. In model 2, the system consists of churner and continuous butter making. Both the units starts to operate to accomodate the demand in winters, on the failure of any one unit the system works on reduced capacity. In summers, the butter churner is operative and CBM is in cold standby state, it operates on the failure of the churner. The system either goes to cold standby or maintenance state when there is no demand.

Methods

Both the models have been analyzed using semi-Markov process and regenerative point technique probabilistically.

2. Annotations

Table 1:

Notations of the model 1

Notations Descriptions

A Failure rate of the main unit i.e. Churner.

A1 Rate of electricity failure due to which churner stops operating.

Y Rate at which churner goes to down state when demand is less than

production.

5 Rate when churner comes to operative state from a cold standby

state.

a Rate of going from winters to summers.

ft Rate of going from summers to winters.

ch Main unit of the system i.e.ch.

S Summer season.

W Winter season.

Och Main unit of the system is in operating state.

d > p Demand is more than production.

d < p Demand is less than production.

CSch Main unit is in cold standby state.

Frch Main unit is under repair.

HCSch Main unit in cold standby state due to electricity hault.

G(t),g(t) c.d.f. and p.d.f of time to repair of the main unit.

G1 (t),gi(t) c.d.f. and p.d.f of time to repair the electricity hault. G2(t),g2(t) c.d.f. and p.d.f of time to going back to operating state from down state.

3. Transition Probabilities and Mean Sojourn Time

Various states of the system are shown in figure 3.1 called as state transition diagram. Here, the states So, Si, S2 are operating states, S5 is a cold standby state whereas, states S3, S4, S&, S7 are the failed states. Transition Probabilités

• dQ01 (t)= ße-(x+ß)(t) dt

• dQ13 (t) = A1 e-(A+Ai)(t) dt

• dQ25 (t) = ye-(Y+A+Ai)(t)dt

• dQo2 (t) = ae-(K+ß)(t) dt

• dQ14 (t) = Ae-(A+Ai)(t) dt

• dQ26 (t) = A1 e-(Y+A+Ai)(t) dt

• dQ27 (t) = Ae-(7+A+A1)(t) dt

The non-zero probabilities p^ are as follows:

• pij=Qij (™) = JT qijdt • po1

• p02=OTP • p13

• p14 = TTX1 • p25

• p26 = Y+XTAT • p27

• p31 = p62 = g *1 (0) • p41 From the above transition probabilities it is verified that:

ß

a+ß

M A+A1

Y

Y+A+Aj A

Y+A+Aj p?2 = g * (0)

poi + p02 = 1

p25 + p26 + p27 = 1

pi3 + pi4 = 1

Figure 1: State Transition Diagram

The unconditional mean time taken by the system to transit for any regenerative state j when time is counted from the epoch of entrance into state i is mathematically state as:

mj = fo°° tdQij(t)dt = -q*j(0) mi3 + mi4 = Ц1

moi + mo2 = Ц0 m25 + m26 + m27 = Ц2

The mean sojourn time ^ in the regenerative state iis defined as time of stay in that state before transition to any other state:

Цо

i

a+ß

Ц2 = Y+A+Ai Ц4 = Ц7 = -g* (0)

Ц1 = A+Ai

Ц3 = Ц6 = -g*(0)

Ц5 = 1

4. Mean Time to System Failure

The average duration between successive system failures, i.e. MTSF is defined as the expected time for which the system is in operation before it completely fails. Mean time to system failure

Upasana Sharma, Drishti RT&A, No 1 (77)

RELIABILITY OF A BUTTER CHURENR AND CBM SYSTEM Volume 19, March 2024

(MTSF) of the system is determined by considering failed state as absorbing state. When the system starts from the state 0, the mean time to system failure is:

To = lim R(s) = lim 1 - (s) = N

0 s—>-0 v ' s—►0 s D

where,

N=(^0+^1 Poi)(1-P25)+(^2+^5 P25)( P02) D=1-P25

5. Availability Analysis of the System in Summers

Availability A, (t) is a measure that allows for a system to repair when failure occurs. The availability of the system is defined as the probability that the system is successful at time t. The long run availability of the system is given by

A0 = lims-^0[sA0s (s)] = D

where, N1=^2 P02

Dl=^2+^5 P25+^0 P26 + P27

6. Availability Analysis of the System in Winters

Availability A, (t) is a measure that allows for a system to repair when failure occurs. The availability of a system is defined as the probability that the system is successful at time t. The long run availability of the system is given by

AW = lims-^0 [sA0w (s)] = §

where, N2=^1 P01

D2=^1+^4 P14+^3 P13

7. Busy Period Analysis for Repair in Summers Busy period B, (t) in summers is defined as the probability that the repairman is busy at time t when the system entered to a regenerative state i. The total time in which the repairman is busy doing repair of the system in steady state is given by:

B0 = lims-^0 [sB0s (s)] = §

where,

N3=P02( P26 H6 + P27^7) D1is already defined above.

8. Busy Period Analysis for Repair in Winters

Busy period B,(t) in winters is defined as the probability that the repairman is busy at time t when the system entered to a regenerative state i. The total time in which the repairman is busy doing repair of the system in steady state is given by:

B0w = lims—[sB0w (s)] = §

where,

N4=Poi(W3 P13 + W4 P14 ) D2is already defined above.

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9. Expected Number of Repairs in Summers

Let V, (t) be the expected number of repairs in (0, t) given that the system entered into regenerative state i at i = 0. The expected number of repairs during summers in steady state is given by:

Vr = lims-^0 sV" (s) =

N5=P02(1 - P25)

D1 is already defined above in equation.

10. Expected Number of Repairs in Winters

Let V, (t) be the expected number of repairs in (0, t) given that the system entered into regenerative state i at i = 0. The expected number of repairs during summers in steady state is given by:

Vr = lims-^0 sV" (s) = D2

N6=P01

D2 is already defined above in equation.

11. Profit Analysis of the System

Profit incurred to the system model in steady state is given by

p = (C0 A0 + C1 AW) - (C2 B0 + C3 BW + C4V + C5VW)

where,

C0=Revenue per unit up time in summers. C1=Revenue per unit up time in winters.

C2=Cost per unit up time for which the repairman is busy for repair in summers. C3=Cost per unit up time for which the repairman is busy for repair in winters. C4=Cost per repair in summers. C5=Cost per repair in winters.

12. Graphical Analysis and Conclusion

For further numerical and graphical evaluation, let us assume the repair and failure rates to be exponentially distirbuted g(t) = 6e-e(t), g1 (t) = Qxe-Q1(t)

• p01 = a+ft • p02=a+ft

• p13 = A+A1 • p14 = A+A1

• p25 = 7+A+A1 • p26 = y+A+A1

A 1

• P27 = 7+X+AI • P31 = P62 = 1

• P41 = P72 = 1 • F0 = a+ft

• ^ = A+A1 • = 7+A+A1

• № = V6 = ^ • ^4 = ^7 = 1

• № = 1

The parameters obtained using the original data collected from the Verka Milk Plant, Bathinda, Punjab.

Table 2:

Parameters obtained from data collected

Parameters for Values

model 1

A .00045892

Ai .0002563

gi (t) .04213

g(t) .062981

a .0004314

ß .000526

5 .000155

Y .000955

Co 830000

Ci 1030000

C2 10500

C3 12500

C4 12000

C5 15500

System effectiveness measures evaluated are given below:

Table 3:

Parameters obtained from data collected

Parameters for model 1 Values

Mean time to system failure 9453.77 hrs

Availability in summers .8975

Availability in winters .8984

Busy period for repair in summers .000485

Busy period for repair in winters .0004204

Expected number of repairs in summers .000217

Expected number of repairs in winters .000031

MTSF v/s Failure Rate A with varying Failure Rate

4Z50

Figure 2: MTSF v/s Failure Rate

Figure 3: Profit v/s Failure Rate in Summers

Figure 4: Profit v/s Failure Rate in Winters

Figure 5: Profit v/s Failure Rate in Winters

Figure 6: Profit v/s Failure Rate in Winters

Table 4:

Notations of the model

Figures Descriptions

5 Profit P1 increases as the revenue C0 increases. C2=10500; Profit >=< according to C2, when C2 is >=<Rs.275.53, similarly for C2=20500 where cut off point is Rs.163.577 C2=30500; where cut off point is Rs. 452.675

6 Profit P2 increases as the revenue Ci increases. C3=12500; Profit >=< according to C3, when C1 is >=<Rs.251.85, similarly for C3=22500 where cut off point is Rs.140.469. C3=32500; where cut off point is Rs. 429.089

Figure 3 and figure 4 depicts the trend of mean time to system failure and profit v/s the failure rate. It has been observed that as the failure rate A of the system increases mean time to system failure and profit decreases. It also decreases on increasing failure rate Ai. Figure 5,6 states that profit increases as the cost C1 increases as well it increases with increasing profit C3. MODEL 2 Assumptions Model 2 have the following assumptions:

• The system is operating at the initial stage.

• At the initial stage the churner is operating and continuous butter making is in a cold standby state.

• Both the systems operates during winters due to high demand.

• Only one unit is operating during summers due to less demand.

• In summers it also undergoes maintenance.

• The system sometimes goes to cold standby state in case of no demand in summers.

• The repair is done on the failure of the system.

• Repair rates are assumed to have arbitrary distribution.

• Failure rates are taken to be exponentially distributed.

• After repair the system operates as new.

• The system goes to failed state either on the failure of the churner or due to hault in the electricity.

13. Annotations for model 2 Table 5:

Notations of the model 2

Notations Descriptions

A Failure rate of the churner.

A1 Failure rate of the continuous butter making.

Y Rate at which churner goes to down state when demand is less than production.

S Rate when churner comes to operative state from a cold standby state.

a Rate of going to winters.

ft Rate of going to summers.

ch Unit churner of the system.

cbm Unit continuous butter making of the system.

S Summer season.

W Winter season.

Och Churner is in operating state.

Ocbm CBM is in operating state.

d > p Demand is more than production.

d < p Demand is less than production.

CSch Main unit is in a cold standby state.

CScbm CBM is in a cold standby state.

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Frch Churner is under repair.

HCSch Churner is in cold standby state due to electricity hault.

G(t),g(t) c.d.f. and p.d.f of time to repair of the churner.

G1 (t),g1 (t) c.d.f. and p.d.f of time to repair of CBM.

G2(t),g2(t) c.d.f. and p.d.f of time to going back to operating state from maintenance.

14. Model 2

15. Annotations for model 2

16. Transition Probabilités and Mean Sojourn Time

Various states of the system are shown in figure 1.5 called as state transition diagram. Here, the states So, S1, S2, S3, S5 are operating states, S4 is a cold standby state whereas, states S9, S10 are the reduced capacity states and rest are failed states.

ae-(«+ft)(0 dt

dQ01 (t) = fte-(a+ft)(t) dt dQ19 (t) = A1 e-(A+A1)(t) dt dQ23 (t) = A2 e(A+A2+Y) dt dQ25 (t) = Ae(A+A2+Y) dt dQ3,13(t) = Ae-A(t) G(t)dt

dQo2 (t) dQ1,10(t) = Ae-(a+ft)(t) dt

dQ24 (t) = 7e(A+A2+Y) dt

dQ32 (t) = g2 (t)e-A(t) dt dQ373)(t) = (Ae-A(t)(c)1)g2 (t)dt

The

dQ42 (t) = öe-ö(t) dt

dQ56 (t) = Ai e-Al (t) G(t)dt

dQ67 (t) = g2(t)dt

dQ/s (t) = Ae-A(t) Gi(t)dt

dQ9i (t) = gi(t)e-A(t)dt

dQ9lio)(t) = (Ae-A(t)(c)l)gi(t)dt

dQio,ii(t) = Aie-Ai(f) G(t)dt

dQi3,/(t) = g2 (t)dt non-zero probabilities p,j are as follows:

p/=Qij = /o°° j P02 = Pi,io

a a+ß

A

A+Ai p24 = A+A2+7 P32 = g2 (A) P52 = g2*)(Ai ) P72 = gi*)(A) P9i = gi*)(A) Pio,i = g(*)(Ai) From the above transition probabilities it is verified

Poi + Po2 = i P23 + P24 + P25 = i

, (i3) 1 P32 + P37 ) = i

P52+p57) = i

(s)

P72 + p/5) = i

P9i + P9112O) = i

( )

P 1 o,l + Pio,9

dQ52 (t) = g(t)e-Al (t) dt

dQ57)(t) = (Ai e-Ai (t))g(t)dt dQ72 (t)= gi (t)e-A(t) dt dQ(S) = (Ae-A(t)(c)l)gi (t)dt dQ9,i2(t) = Ae-A(t) Gi(t)dt dQio,i(t)= g(t)e-Al(t)(t) dt dQioi9(t) = (Ai e-Ai (t)(c)l)g(t)dt dQi2,io (t) = gi(t)dt

Poi Pl9

ß

a+ß

Ai

A+Al

A2

P23 = A+A2+7 A

P25

A+A2+7

1 - g2 (A)

(13)

P3,13 = P37 )

P56 = p57) = 1 - g22)(Ai)

P7S = p7? = 1 - g(2) (A) P9,12 = P9ll2o) = 1 - gi*)(A)

Pio,ii = Pllol9) = 1 - g(2)(Ai) that:

Pl9 + Pl,io = 1 P32 + P3,13 = 1 P52 + P56 = 1 P72 + P7S = 1 P91 + P9,12 = 1 Pio,i + Pio,ii = 1

1

The unconditional mean time taken by the system to transit for any regenerative state j when it (time) is counted from the epoch of entrance into state ¿is mathematically state as:

mj = fo°° tdQij(t)dt = -q2(o)

mi9 + mi,io = Ui m32 + №3,13 = U3 m52 + m56 = U5 №72 + №75 = U7 №91 + №9,12 = u9 mio,i + rnio,ii = Uio

rnoi + rno2 = Uo

№23 + №24 + №25 = U2

K2

, (13) №32 + rn37 ;

№52 + rn57) = K

№72 + rn75) = Ki

(12) ix

№91 + rn9,lo = Ki

(11) V

№io,l + №lo,lil = K

Figure 7: Model 2: State Transition Diagram

The mean sojourn time Ui in the regenerative state ¿is defined as time of stay in that state before transition to any other state:

• № = a+ß

• U2 = 7+A+A2

• U = 1

• Fi = s

U1

A+A1

U7 = U9

1-g1*)(A)

Uli = /o°° G(t)dt

= i-g2 (Ai) U3 = A1

U. = 1-g* (Al) U5 = A 1

= (A1) U10 = A1

U12 = /0° Gi(t)dt

17. Mean Time to System Failure for Model 2

The average duration between successive system failures, i.e. MTSF is defined as the expected time for which the system is in operation before it completely fails. Mean time to system failure (MTSF) of the system is determined by considering failed state as absorbing state. When the system starts from the state 0, the mean time to system failure is:

To

limo R*(s)

s—y 0

lim

s—► 0

1 - tO* (s)

N D

where,

D=Pl9P23P32P9i - P24 - P25P52 - Pl9P91 - Pl0,1 Pl,10 - P23P32 + Pl9P24P91 + Pl9P25P52P91 +

P23 P32 Pl0,1 Pl,10 + P24 Pl0,1 Pl,10 + P25 P52 Pl0,1 Pl,10 + 1

N = U0 (P23P39 + P25P56 - Pl9P23P39p91 - Pl9P25P56p91 - P23P39Pl0,1 Pl,10 - P25P56Pl0,1 Pl,10) +

Ul (P91 + P01 P9,12 - P23P32P91 - P24P42p91 - P25P52p91 - P02P23P39p91 - P02P25P56p91 -

P01P23P32P9,12 - P01P24^42^9,12 - P01P25P52P9,12) + (U2 + U4p24)(¡^2 - ¡^2¡P91 -

P42P10,1 P1,10 - P01P19P42P9,12 - P01P42P1,10P10,11) + U3(P02P23 - P02P19P23p91 -

P02P23P10,1 P1,10) + U5(P02P25 - P02P19P25p91 - P02P25p10,1 P1,10) + U9(P01P19 - P01P19P23P32 -

P01P19P24P42 - P01P19P25¡M + U10(P01 P1,10 - P01P23P32P1,10 - P01P24P42p1,10 - p01 P25P52P1,10)

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A

s

18. Reliability Measures

18.1. Availability Analysis in Summers

Availability A(t) is a measure that allows for a system to repair when failure occurs. The availability of a system is defined as the probability that the system is successful at time t. The long run availability of the system is given by

A0 = lims—^o[sA0s (s)] = D

where,

N=Ho + H2P02 + H3P02P23 + H5P02P25 - HoP23P32 - HoP24 - HoP25P52 - HoP§ P75 +

(13) , (6) (13) (6) (8) (6)

H7Po2P23P37 ) + H7Po2P25P57) - HoP23P37 ) P72 - H2Po2P57) P75 - HoP25P57 P72 +

(13) (8) (6) (8) (6) (8) (13) (8) (6) (8)

H5Po2P23P37 ) P75) - H3Po2P23p57) P75) + HoP23P32p57) P7s - HoP23P37 ) P52p75) + HoP24P57) P75)

D1=(H2 + H4P24)(1 - P57)P75)) + H3(P23P72 + P23P52p^ + H5(p75 + P25P72 - P23P32p75 -

(8)\ , t (6) (6) , (13) (6)N

P24P75)) + H7(P57) - P23P32p57) + P23p37 )P52 - P24p5^

18.2. Availability Analysis in Winters when the System Works at Full Capacity

The availability of a system is defined as the probability that the system is successful at time t. The long run availability of the system is given by

A = lims^oMos (s)] = D2

where,

(11) (12) (11) (11) (12) N2 = Ho + H1 Po1 - HoP19P91 - HoP1o,1 P1,1o - HoP1o 9 P91o - HoP91 p1o 9 P1,1o - H1 Po1 P1o 9 P9 1o -(12)

Ho P19 P1o,1 P9,1o;

D2 = H1 (P1o,1 + P91 P1o,9 ) + H9 (P1o,9 + P19 P1o,1) + H1o( P1,1o + P19 P9,1o)

18.3. Availability Analysis in Winters when the System Operates at Reduced

Capacity

Availability of the system when it operates at reduced capapcity is given by

where, N3 = p(

D2 is already defined above.

AW = lims—^0 [sA0w (s)] = g N3 = P01 (^9 P19 + ^10 P1,10 + H9 P^ P1,10 + ^10 P19 p9110))

18.4. Busy Period Analysis for Repair in Summers

Busy period B,(t) in summers is defined as the probability that the repairman is busy at time t when the system entered to a regenerative state i. The total time in which the repairman is busy doing repair of the system in steady state is given by:

B0r = lims—^0 [sB0sr (s)] = N1

where,

N4=P02(^5 P25 + H7 P23 p373) + F7 P25 p57) + F5 P23 p373) p785) )

D2is already defined above.

18.5. Busy Period for Maintenance in Summers

Busy period B, (t) in summers for maintenance is obtained. The total time in which the repairman is busy doing repair of the system in steady state is given by:

B0m = lims—^0 [sB0sm (s)] = g

where,

N5=-^3P02P23(P57)P75) - 1) D2is already defined above.

Upasana Sharma, Drishti RT&A, No 1 (77) RELIABILITY OF A BUTTER CHURENR AND CBM SYSTEM_Volume 19, March 2024

18.6. Busy Period Analysis for Repair in Winters

Busy period for repair in winters is obtained as given below:

The total time in which the repairman is busy doing repair of the system in steady state is given by:

B0wr = lims—^q [sBQwr (s)] = g

where,

N6 = P01 (^9P19 + ^l0pi,10 + V-9P109 P1,10 + ^10P19p91l0) D2is already defined above.

18.7. Expected Number of Repairs in Summers

Let V(t) be the expected number of repairs in (0, t) given that the system entered into regenerative state i at i = 0.

The expected number of repairs during summers in steady state is given by:

Vsr = lims—^0 sVsr (s) = g

N7 = P02 ( P25 P52 + P25 p57 + P23 p373) P72 + P23 p373) p75 + P25 p57 P72 + P25 p57 P75 +

(13) (8) . (13) (6) (8)n P23P37 ) P52P75) + P23^7 ) P57 D1 is already defined above.

18.8. Expected Number of Maintenances in Summers

Let V (t) be the expected number of maintenances. The expected number of repairs during summers in steady state is given by:

Vsm = lims_^0 sVsm (s) = D

g8 = -( P32+P373)) P02 P23( P57) P75) -1) D1 is already defined above.

18.9. Expected Number of Repairs in Winters

Let Vi (t) be the expected number of repairs in winters. The expected number of repairs during summers in steady state is given by:

Vwr = lims_^0 sVwr (s) = g

N9 = P01 ( P19 P91 + P10,1 P1,10 + P10,9 P1,10 + P19 p9ÏÏ + P91 P10,9 P1,10 + P19 P10,1 j^lö + P19 P10,9 J^O +

P10,9 P1,10 P9,10 )

D2 is already defined above.

19. Profit Analysis of the System

Profit incurred to the system model in steady state is given by

P = (CoAO + CiA^ + C2AWr) - (C3B0 + C4BW + C5B0m + C6V?r + C7V + CsVT)

where,

Co=Revenue per unit up time in summers.

C1=Revenue per unit up time in winters when the system operates at full capacity. C2=Revenue per unit up time in winters when the system operates at reduced capacity. C3=Cost per unit up time for which the repairman is busy for repair in summers. C4=Cost per unit up time for which the repairman is busy for repair in winters. C5=Cost per unit up time for which the repairman is busy for maintenance in summers. C6=Cost per repair in summers. C7=Cost per repair in winters. Cs=Cost per maintenance in summers.

20. Graphical Analysis and Conclusion

For further numerical and graphical evaluation, let us assume the repair and failure rates to be exponentially distirbuted

g(t) = 0e-e(t), g1 (t) = Qxe-Q1(t), g2 (t) = 02e-02(t)

Poi

P19 P23 P25

ß

a+ß

Ai

A+A1

A2 A+A2+7

A

A+A2+7

P(13) = = 92 p37 = p3,i3 = A1+F52

P57 = p56 = Xf+0

P(8) = Pna = 01 p75 = p78 = ÄT&T

(12)

P9,10 = P9,12 = (12)

P1o,11 = P10,12 :

mu1 = ÂTAT = °2

V3 = A1 (A1 +02)

91 A+01

_ 9 A1 +9

U5 = ^13

^10 = A1(A1+9)

J_

02

F6 = g

P02 = P1,10 P24 = P32 = P52 = P72 = P91 =

P10,1 H0 = V2 = ^4 = V7 = V8 =

a a+ß

A

A+A1 7

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A+A2+7

A1 A1+02

A1 A1+9

A A+01

A

A+01

-

= A1+0

1

a+ß 1

7+A+A2

1

5

^9 = V12

01

A(A+01 ) _ J_

" 01

The parameters obtained using the original data collected from the Verka Milk Plant, Bathinda, Punjab.

Table 6:

Parameters obtained from data collected

Parameters for Values

model 1

A .00045892

A1 .0004567

A2 0.000246572

g1 (t) .06312

g(t) .062981

g2 (t) 0.002628867

a .000562

ß .0004314

5 .000955

7 .000155

C0 830000

C1 1030000

C2 61660

C3 10500

C4 12500

C5 15500

C6 19500

C7 6400

C8 7000

System effectiveness measures evaluated are given below:

Table 7:

Parameters obtained from data collected

Parameters for model 2 Values

Mean time to system failure 99682.28 hrs

Availability in summers 0.985

Availability in winters when system oper- .989

ates at full capacity

Availability in winters when system oper- .001435

ates at reduced capacity

Busy period for repair in summers .003814

Busy period for maintenance in summers .038744

Busy period for repair in winters .007864

Expected number of repairs in summers .000242

Expected number of maintenances in sum- .000120

mers

Expected number of repairs in winters .000499

Figure 8: MTSF v/s Failure Rate

Figure 9: Profit v/s Failure Rate in Summers

Figure 10: Profit v/s Failure Rate in Winters

Figure 11: Profit v/s Failure Rate in Winters

Figure 12: Profit v/s Failure Rate in Winters

Table 8:

Notations of the model

Figures Descriptions

11 Profit P1 increases as the revenue C0 increases. C3=10500; Profit >=< according to C3, when C3 is >=<Rs.645.34, similarly for C3=20500 where cut off point is Rs.573.039 C3=30500; where cut off point is Rs. 500.7389

12 Profit P2 increases as the revenue C1 increases. C4=12500; Profit >=< according to C4, when C1 is >=<Rs.203.345, similarly for C4=22500 where cut off point is Rs.460.203. C4=32500; where cut off point is Rs. 317.061

The MTSF, profit in the summers (P1), and profit in the winters (P2) graphs 8,9,1o exhibit a similar trend with failure rate lambda and A1, which means that as the failure rate rises, the MTSF and profit fall.

21. Conclusion

The significance of implementing dependability in verka milk plant is analysed and concluded upon in this study. Using the parameters laid out in tables above, it has been shown that the second model generates more money after CBM is put into effect. Results from mathematical measurements and graphs showing that MTSF and Profit drop with increasing values of failure rates must be used to gain a more in-depth understanding of the essential real influencing elements and, in turn, enhance the reliability model. But the equations derived for MTSF, assessments of the system's functionality, and profit can be used to find alternative cut-off points related to the required rates, costs, and probabilities involved. The formulas for the proposed system can then be generated by plugging in the actual numbers for the relevant rates and costs. Important decisions about the system's dependability and profitability can be made with the help of graphs showing cut-off points for key rates, costs, and revenue.

References

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[4] Ram, Mangey and Singh, Suraj Bhan and Singh, Vijay Vir. Stochastic analysis of a standby system with waiting repair strategy, 2o13.

[5] Verdejo, Humberto and Awerkin, Almendra and Saavedra, Eugenio and Kliemann, Wolfgang and Vargas, Luis. Stochastic modeling to represent wind power generation and demand in electric power system based on real data, 2o16.

[6] Sharma, Rajiv Kumar and Kumar, Sunand. Performance modeling in critical engineering systems using RAM analysis, 2oo8.

[7] Kumar, Ashok and Agarwal, Manju. A review of standby redundant systems, 198o.

[8] Aggarwal, Anil Kr and Singh, Vikram and Kumar, Sanjeev. Availability analysis and performance optimization of a butter oil production system: a case study, 2o17.

[9] Arthur, Neil. Dairy processing site performance improvement using reliability centered maintenance,2oo4.

Upasana Sharma, Drishti RT&A, No 1 (77) RELIABILITY OF A BUTTER CHURENR AND CBM SYSTEM_Volume 19, March 2024

[10] Sharma, Upasana and Kaur, Jaswinder. Study of two units standby system with one essential unit to increase its functioning,2016.

[11] Sharma, Upasana and Kaur, Jaswinder.Cost benefit analysis of a compressor standby system with preference of service, repair and replacement is given to recently failed unit, 2016.

[12] Sharma, Upasana and Kaur, Jaswinder. Evaluation of Various Reliability Measures of Three Unit Standby System Consisting of One Standby Unit and One Generator, 2016.

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