SIX WEEKS SUMMER INTERNSHIP REPORT

ON

REJECTION ANALYSIS OF TRAILER CONTROL VALVE

Submitted by

Bikash Chandra Samantray

Reg. No-11109624

Section- M1112

Under the Guidance of

K. Sudhakar (Head of Department – Vehicle Dynamics Control)

WABCO INDIA PVT. LTD,

Ambattur, Chennai

School of Mechanical Engineering

Lovely Professional University, Phagwara

Acknowledgements

I take this opportunity to thank each and every individual who gave me this wonderful platform to complete my internship successfully.

I could not have done this work without the constant support from the entire team of WABCO INDIA LTD. The environment inside the plant is truly professional and this is what motivated me the most. The official staffs are very co-operative and it is because of this that work stress is never felt while working here.

I would specially like to thank Mr. K. Sudhakar and Mr. Bagavathi who gave me the opportunity to work on a project. Not only they advised me on new ideas about the project but also considered my ideas for further improvements in the project. I would like to thank Ms. Suganya (Sr. Engineer), Mr. S.Karthick (PED), Mr. Manikandan (Group Leader) and Mr. Elumalai (Quality Dept.) for their valuable advice and contribution.

Bikash Chandra Samantray

Third year B.Tech (Mechanical)

ABSTRACT

The report consists of the following tasks which were carried out at the factory during the summer internship.

i. Observation of the Assembly of Trailer Control Valveii. Collection of Rejection Data from 23.6.2014 to 11.7.2014

iii. Analysis of the Rejection Dataiv. Control measures suggestedv. Result after implementation of Control measures

Certain control measures implementation in progress.

CONTENTS

I. Chapter No. 1 – (Organizational Overview)-------------------------------------Page 1-6

II. Chapter No. 2 – (project Description)---------------------------------------------Page 7-13

Introduction to TQM --------------------------Pg. 8 Importance of TQM----------------------------Pg. 8-9 Techniques in TQM----------------------------Pg. 9-10 Working of TCV -------------------------------Pg. 11-12 Layout of Tractor ------------------------------Pg. 13

III. Chapter No. 3 – (Implementation Detail)----------------------------------------Page 14-29

Flow Chart --------------------------------------Pg. 14 Observation of Assembly ---------------------Pg. 15 Collection of Data ------------------------------Pg. 16 Analysis of Rejection Data --------------------Pg. 17-28 Actions Suggested ------------------------------Pg. 29-30

IV. Chapter No. 4 – (Result and Conclusion)----------------------------------------Page 31- 33

Results ---------------------------------------------Pg. 31 Benefits--------------------------------------------Pg. 32 Conclusion ----------------------------------------Pg. 33

V. Chapter No. 5 – (Gantt. Chart)-----------------------------------------------------Page 34

CHAPTER - 1

ORGANIZATIONAL OVERVIEW

WABCO INDIA LIMITED, WABCO India designs, manufactures and markets conventional braking products, advanced braking systems, and other related air assisted products and systems. The company has grown significantly in the Indian commercial vehicle market. WABCO India serves its aftermarket customers through a wide national distribution network. With five world-class manufacturing facilities, software design center and a test track in India, WABCO India excels in engineering and manufacturing. WABCO India employs over 3,200 employees and reported Rs. 1138 Crores in sales in 2013-14.

WABCO (NYSE: WBC) is a leading global supplier of technologies and control systems for the safety and efficiency of commercial vehicles. Founded nearly 150 years ago, WABCO continues to pioneer breakthrough electronic, mechanical and mechatronic technologies for braking, stability and transmission automation systems supplied to the world’s leading commercial truck, bus and trailer manufacturers. With sales of $2.7 billion in 2013, WABCO is headquartered in Brussels, Belgium.

WABCO GROUP CUSTOMER VALUES

In 2009, WABCO initiated two strategic Customer Value Teams (CVTs) to align with technology trends that are relevant to our customers.

One CVT drives vehicle efficiency and environmental sustainability, while our other CVT drives advanced safety and driver effectiveness. Each team develops concepts for new products and systems to maximize value for customers by leveraging all of WABCO’s technologies and capabilities.

Vehicle Efficiency and Environmental Sustainability

WABCO’s vision toward 2020 is to support the commercial vehicle industry to achieve its target of improving fuel efficiency by 20 percent and reducing carbon dioxide (CO2) emissions by 20 percent.

Our CVT is further powered by WABCO’s global engineering network. By devising innovation strategy from deeper understanding of diverse customer roadmaps, we can develop and deliver technologies that increase fuel efficiency, reduce vehicle weight, optimize energy recovery, and achieve other efficiency and environmental enhancements for commercial vehicles on a continual basis.

Advanced Safety and Driver Effectiveness

WABCO has a vision to improve vehicle safety while strongly contributing to driver effectiveness. Our strategy involves reducing the number of commercial vehicle accidents by 50 percent by 2020.WABCO’s industry-leading portfolio of vehicle safety technology addresses nearly every type of road accident. Our CVT, which also includes engineering and manufacturing experts, anticipates customer needs. Connected with customers and aligned with their technology roadmaps, our CVT develops new products and functionalities to better meet the future needs of original equipment manufacturers everywhere.

The Power of Technology

Our CVTs are committed to contributing to the long term success of our customers. We further leverage WABCO’s powerful technology portfolio and experience in established markets. We

also help satisfy the rapidly rising demand for advanced solutions in emerging markets where commercial vehicle producers are accelerating their adoption of higher safety and environmental standards.Customers

i. Tata Motors Ltd., Puneii. Tata Motors Ltd., Lucknow

iii. Volvo Commercial Vehicles, Bangaloreiv. Daimler India Commercial Vehicles, Chennai

v. Ashok Leyland Ltd., Chennai etc.

AWARDS AND RECOGNITIONS

i. Ashok Leyland Award for Excellence in Quality- 2009

ii. Best New Product Development 2009 – Volvo Group

iii. Best Quality Medal in World

and many more …

SOME WABCO INDIA PRODUCTS

1. Anti-Lock Braking System – Anti-Lock Braking Systems (ABS) are used to prevent locking of a vehicle’s wheels as a result of excessive actuation of service braking system, especially on slippery roads.

2. Relay Valve – WABCO’s Relay Emergency Valve is normally used in trailer braking systems. It is a dual function valve, combining the functions of relay valve and an emergency valve which are:

a) The application and release of trailer brakes

b) The emergency application of the brakes in the event of accidental decoupling of the trailer

Features: Designed for either reservoir or frame mountings

Benefits : Provides support to the Trailer of the Vehicle

Applications : Trailer

3. Trailer Control Valve – WABCO’s Trailer Control Valve is engineered to control the vehicle’s trailer braking with a tractor-trailer combination. The major functions of this valve include:

Normal charging of trailer reservoir when no brake application is made It supplies increased pressure to the trailer brakes during normal service brake application Application of trailer brakes when the foot brake valve primary circuit has failed Application of trailer brakes when tractor spring brakes are actuated Protect the tractor circuit by activating dump feature when either supply or control line

fails

4. Brake Chamber – WABCO’s Brake Chamber converts the air pressure into mechanical output force.

Apart from these products, WABCO also manufactures Drying And Distribution Unit (DDU), Electronic Braking System etc.

CHAPTER - 2PROJECT DESCRIPTION IN BRIEF

I. Name of Project – Rejection Analysis of Trailer Control Valve

II. Task – To observe the rejection in TCV Line and suggest and implement suitable methods to reduce the rejection and improve the Quality of the Product .

III. Product Description - Trailer Control Valve is engineered to control the vehicle’s trailer braking with a tractor-trailer combination. The major functions of this valve include:

Normal charging of trailer reservoir when no brake application is made It supplies increased pressure to the trailer brakes during normal service brake application Application of trailer brakes when the foot brake valve primary circuit has failed Application of trailer brakes when tractor spring brakes are actuated Protect the tractor circuit by activating dump feature when either supply or control line

fails

IV. Team Membersa) Mr. K. Sudhakar – (H.O.D – Vehicle Dynamics Control-1)b) Mr. K. Bagavathi- ( Production Leader)c) Mr. J. Elumalai – (Quality Dept.)d) Mr. Bikash Chandra Samantray (Project Trainee)

V. Name of the Department where the Project was carried out – Quality Assurance Department (QAD)

VI. Quality Tools Used – Pareto Chart, Charts (Bar Graph), Fault Tree Analysis

Brief Description about the need for Quality in a product

INTRODUCTION TO TOTAL QUALITY MANAGEMENT (TQM)

Quality management is a business principle that ensures excellence in a company's products, services and internal processes. Companies that implement quality management programs use the information from them to identify weaknesses, faults, areas for improvement and strengths. This gives the company the ability to set standards, make adjustments as needed and to offer greater value overall to their customer base. Although the approach to solving quality issues varies with different programs, the goal remains the same – to create a high quality, high-performing product or service that meets and exceeds internal and external customer expectations. When companies focus on quality management, they create a plan for success.

IMPORTANCE OF TQM

I. Product Performance

Quality management programs improve a company's product. The primary aspects of product quality management start with performance, reliability and durability of the product. With quality management programs, manufactured products undergo testing to verify they perform according to its stated promises or features. This allows a company responsiveness to change problem areas or improve product strengths. By adding quality management aspects at the design phase of new products, for example, this allows companies to design performance benchmarks into the product.

II. Customer Satisfaction

These programs can also help to ensure customer satisfaction. By including customer surveys in the QM program, key personnel gain understanding of the product features important to consumers. By widening the survey scope to include noncustomers, this provides additional insight into why these people use the services of the competitor, allowing the company to integrate these features into their products. Feature-specific surveys can target the areas of a product or service that need improvement or work well already. These types of programs can help a business create products that customer’s desire.

III. Reduce Waste

A well-thought out quality management program can also help companies reduce waste. Manufacturing companies, for example, that house raw material inventory pay for its storage, management and tracking. These costs are built into the price of the product. By implementing a supply-chain management program, a company can reduce the raw materials it has to keep on hand, saving money and valuable space. Such a system injects a systematic approach to keeping raw material needs equal to production requirements, which can help to bring down product costs overall, improving the product's profit margin.

IV. Enhanced Productivity

Quality management programs also can identify areas for improvements in internal processes. This approach can impact productivity by eliminating unnecessary tasks or improving existing ones. It also generates teamwork when a company implements employee-based mixed departmental teams that review internal processes. An example of this is the balanced scorecard approach. This methodology provides a mechanism for evaluating department operations against benchmarked performance expectations. This type of quality program identifies how well individual areas of the company perform when compared with its established goals. It defines whether a company needs to streamline or re-engineer its internal processes.

V. Increased Revenues

Quality management programs help companies establish standards of operation in all departments. By using these programs in multiple areas, a company can identify the strategies it needs to implement. Through these programs, it can improve its reputation among its existing customers, which can also help it attract new ones. This results in employees spending less time and raw material inventory to produce quality products or services. This recaptures lost monies while refining product and service excellence, ultimately leading to increased revenues and a better bottom line.

TECHNIQUES IN TQMSix sigma, JIT, Pareto analysis, and Five Whys technique are all approaches that can be used to improve overall quality.

I. Six Sigma

Six Sigma drew inspiration from the quality improvement methodologies of preceding decades, including quality control, TQM, and Zero Defects. It aims to improve the quality of a process by identifying the causes of defects and removing them in order to minimize variability in manufacturing and business process. Like TQM, the Six Sigma philosophy includes a belief that achieving sustained quality improvement requires commitment from the entire organization, particularly from top-level management. The main difference between TQM and Six Sigma is that, at its core, TQM is a management approach to long-term success through customer satisfaction. In a TQM effort, all members of an organization participate in improving processes, products, services, and the culture in which they work.

II. Just in Time (JIT)

The Just in Time (JIT) method is a production strategy that aims to improve business return on investment by reducing in-process inventory and associated carrying costs. JIT focuses on continuous improvement and can improve a manufacturing organization's return on

investment, quality, and efficiency. The JIT inventory system focuses on having "the right material, at the right time, at the right place, and in the exact amount" and sees inventory as costly. JIT programs often include a focus on Total Quality Control. For example, it is said that at Toyota, when a process or parts quality problem surfaced on the production line, the entire production line had to be slowed or even stopped.

III. Pareto analysis

Pareto Analysis is a statistical technique that is used to select a limited number of tasks that produce significant overall effect. It uses the Pareto principle, which states that the majority of the problems may be caused by only a few key causes. Pareto analysis also concludes that 80% of the result can be generated by focusing on 20% of the key work.

IV. 5 Whys

The 5 Whys is a question-asking technique used to explore the cause-and-effect relationships underlying a particular problem. The primary goal of the technique is to determine the root cause of a defect or problem which points toward a process that is not working well or does not exist. The technique was originally developed by Sakichi Toyoda and was used within the Toyota Motor Corporation during the evolution of its manufacturing methodologies. It is now used within Kaizen (continuous improvement), lean manufacturing, and Six Sigma.

TRAILER CONTROL VALVE WORKING

FunctionThe Trailer Control Valve is used to control to control a twin line Braking System on a trailer from the vehicle’s Dual Brake Valve and Hand Control Valve.

The major functions of this valve include:

Normal charging of trailer reservoir when no brake application is made It supplies increased pressure to the trailer brakes during normal service brake application Application of trailer brakes when the foot brake valve primary circuit has failed Application of trailer brakes when tractor spring brakes are actuated Protect the tractor circuit by activating dump feature when either supply or control line

fails

WORKING OF TCV

Brakes Off Position a) When the Brakes are not being applied, the air supply enters the Port 11 acting underside

piston of Dump Feature pushing it upwards against the spring force.b) The air supply then passes to chamber C and port 12 to the emergency reservoir in the

trailer through the relay valve.

Brakes Fully Applied

a) When the dual brake on the tractor is operated air enter port 41 and 42b) Through ports 41 chambers A and G are charged and the air pressure acts upon

pistons(M632301 and M632311) and they act downwards.c) When the piston M632301 contacts piston valve, it closes the exhaust and sun

sequentially opens inlet .d) The air from chamber C then flows through chamber B and port 22 into the trailer signal

line in proportion to the pressure from the primary delivery port of the Dual Brake Valve.

HAND BRAKE APPLICATION

When the Graduated Hand Control Valve Brake position in ‘ON’ position air pressure from the chambers D and port 43 is depleted. Automatically the piston is pushed up by the air pressure in chamber and in turn the M610241 valve gets into contact with the piston M632301 closing the exhaust passage, opening inlet passage (f) and air is supplied to the chamber B and port 22.

LAYOUT FOR TRACTOR

PORT 41

PORT 43

PORT 42

PORT 11

DUMP FEATURE

Chamber AChamber G

Chamber C

Chamber B

CHAPTER - 3IMPLEMENTATION DETAILS

FLOW CHART

Observation of the Assembly Process

1. Stage 1 – Plunger and Piston Valve Assembly2. Stage 2 - Tension Pin Assembly3. Stage 3 - Upper Body Assembly4. Stage 4 - Seal Assembly5. Stage 5 - Dump Body Assembly6. Stage 6 - Middle Body Assembly7. Stage 7 - Voss Fitting8. Stage 8 - Leak Testing9. Stage 9 - Venting guide Assembly and Packing

COLLECTION OF DATA

In this stage, the rejection data was collected from 23.6.2014 to 11.7.2014 for shift A (Day Shift) and a graph was made.

INOUT

The above graph gives the information that in 3 weeks totally 805 units of TCV was produced out which 132 units were rejected.

The percentage rejection is 17 %.

ANALYSIS OF REJECTION DATA

From the Rejection Data found, an analysis was done to find the different types of leak which contributed to the rejection. The following graph shows the different kinds of leak that contributed to the rejection.

Explanation of the graph

The blue bar represents 1st week data, the red bar represents the 2nd week data and similarly the green bar represents the 3rd week data.For example, the No. of Rejections due to 11 Leak in the 1st week is 14, in the 2nd week it is 12 and finally in the 3rd week is 16. The same method follows for the other types also.

PARETO ANALYSIS

Now it’s time to see which mode of leak has the maximum contribution to rejection. This is done with the help of a Pareto Chart.

Pareto Analysis is a statistical technique that is used to select a limited number of tasks that produce significant overall effect. It uses the Pareto principle, which states that the majority of the problems may be caused by only a few key causes. Pareto analysis also concludes that 80% of the result can be generated by focusing on 20% of the key work.

Below is the Mode of Leak Pareto Chart

The graph gives us this information that 11 Leak, Upper Joint Leak, Port 43 On Leak and Lower Joint Leak contribute 80% to the total rejection.In order to reduce the percentage of rejection, we need to focus at these four factors one by one.

REDUCTION OF LEAKS

In order to reduce the No. of Rejections due to leak we first have to find out the probable causes and after listing the probable causes we have to validate each cause and then point out at the root cause. This is done with the help of Fault Tree Analysis.

Now what is Fault Tree Analysis?

Fault tree analysis (FTA) is a top down, deductive failure analysis in which an undesired state of a system is analyzed using Boolean logic to combine a series of lower-level events. This analysis method is mainly used in the fields of safety engineering and reliability engineering to understand how systems can fail, to identify the best ways to reduce risk or to determine (or get a feeling for) event rates of a safety accident or a particular system level (functional) failure. FTA is used in the aerospace, nuclear power, chemical and process, pharmaceutical, petrochemical and other high-hazard industries; but is also used in fields as diverse as risk factor identification relating to social service system failure.

In aerospace, the more general term "system Failure Condition" is used for the "undesired state" / Top event of the fault tree. These conditions are classified by the severity of their effects. The most severe conditions require the most extensive fault tree analysis. These "system Failure Conditions" and their classification are often previously determined in the functional Hazard analysis.

FTA can be used to:

Understand the logic leading to the top event / undesired state. Show compliance with the (input) system safety / reliability requirements. Prioritize the contributors leading to the top event - Creating the Critical

Equipment/Parts/Events lists for different importance measures. Monitor and control the safety performance of the complex system (e.g., is a particular

aircraft safe to fly when fuel valve x malfunctions? For how long is it allowed to fly with the valve malfunction?).

Minimize and optimize resources. Assist in designing a system. The FTA can be used as a design tool that helps to create

(output / lower level) requirements. Function as a diagnostic tool to identify and correct causes of the top event. It can help with

the creation of diagnostic manuals / processes.

Let’s have a look at Fault Tree Analysis for 11 Leak

Here Middle Body, Piston Valve Seating and M632311 Piston are the probable causes for 11 Leak.

In Middle Body, Porosity, cuts, and accumulation of foreign particles are the possible causes. Similarly Piston 632301 and Piston Valve are the probable causes for Piston Valve Seating. Similarly for Piston M632311 Porosity, cuts and foreign particles are the possible causes.

Middle Body M632301 Piston M632311 Piston

Now we need to validate every Probable cause and point out at the root cause.

FAULT TREE ANALYSIS FOR UPPER JOINT LEAK

Piston Valve

Here the probable causes are M630430 O Ring and Upper Body. Now let’s looks at the factors to be validated.

FAULT TREE ANALYSIS FOR 43 LEAK

The probable causes are Middle O Ring and Middle Body.The factors to be validated are given in the next page.

FAULT TREE ANALYSIS FOR LOWER JOINT LEAK

The probable causes for Lowe Joint Leak are Lower Body Porosity and Middle Body Cuts. Let’s look at the factors which need to be validated.

Now in order to figure out the root cause we need to validate every factor and find out its connection with the leak.

VALIDATION

Piston Valve Cut Marks/Foreign Particles

The accumulation of foreign particles on the surface of the Piston Valve clearly tells us that this is a significant cause. M632301 Piston Cut Marks

The cut marks on surface of the piston are a significant cause.

M632301 Piston Dimension Problem

Middle Body Porosity

Blow Holes on the surface of the Middle Body are a significant cause.

M632311 Piston Foreign Particles

Accumulation of Foreign Particles on the piston contributes to the leak.

Upper Body Porosity

Presence of blowholes on the inner side of the Upper body is a significant cause. They contribute to Upper Joint Leak.

Lower Body Porosity

Presence of blowholes on the outer surface of the Lower body is a significant cause. They contribute to Lower Joint Leak.

Now as we have validated every cause we need to find what factors are the root causes and accordingly we need to decide what actions need to be taken.

ACTIONS SUGGESTED AND PLANNED

5W2H Analysis

ACTION NO 1 WHAT ACTION? – Washing of all child parts in Ultrasonic Machine WHY? – To remove dust and Burr from the child parts WHEN? – The action is to be carried out before the shift starts WHERE? – Inside Plant premises WHO? – Washing Operator and Part Delivery Staff (Spiderman) HOW? – Washing of Tray and all Child Parts HOW MANY? - All the parts

ACTION NO 2

Ultrasonic Washing Machine

WHAT ACTION? - Segregation of GOOD parts from the lot. WHY?–To avoid supply of parts with cuts and scratches to Assembly Line WHEN? – Immediate action WHERE? – Incoming inspection Area WHO? – Incoming inspector HOW? – Visual segregation/Measurement of dimensions HOW MANY? - All the parts

ACTION NO 3 WHAT ACTION? - Impregnation WHY? – To seal the blowholes and pinholes WHEN? – Immediate action WHERE? – Impregnation Section WHO? – Impregnation staff HOW? – Using Impregnation Machine HOW MANY? - All the parts

CHAPTER - 4

RESULT AFTER IMPLEMENTATION OF ACTIONS

Now as we have implemented the suggested actions it’s time to look at the results and analyze whether the proposed methods where effective or not.This can be explained with the help of the graph.

23.7.2014

24.7.2014

25.7.2014

26.7.2014

28.7.2014

29.7.2014

30.7.20140

2

4

6

8

10

12

811

11

6

45

6

% Rejection

% Rejection

The above graph shows a decline in the rejection percentage from the initial condition (i.e. 17%) to average 7%.

SUGGESTIONS WHICH CAN BE IMPLEMENTED IN FUTURE

Change in the Design of Middle Part i.e. the inner surface of the body is not machined. Use of UV Pinhole Detector Torch to detect Blow holes and Pinholes (mfg. Elcometer

Pvt. Ltd.)

BENEFITS

PRODUCTIVITY – Productivity has increased since the No. of Rejections has gone down and the efficiency has increased from 83% to 93%.

QUALITY – Quality has improved and No. of scrap has decreased. COST – The economic loss due to rejections have come down and there is a increase

in profit. ZERO LINE STOPPAGES – Line stoppages have been eliminated and quality

material have been started getting supplied from the inventory to the assembly line. MORALE OF OPERATORS – Morale of the operators have boosted and there is a

increase in their confidence level. SAFETY – Safety has increased.

CONCLUSION

It was a wonderful experience working at WABCO INDIA PVT. LTD. I gained a lot of insight regarding the Production Line and the Quality Department. The friendly welcome from all the employees is appreciating, sharing their experience and giving their piece of wisdom which they have gained in the long journey of work. I also thank WABCO INDIA LTD for providing me with the food facility. I am sure that the qualities I learnt will surely help me in shaping my future.