Environmental Sustainability of Automotive Radiator Management Assessment Answer

• Subject Code : UEENEEK145A
• Subject Name : Environment Management

Environmental Sustainability Management Assessment Answer

Introduction

Every company has an obligation to be environmentally friendly, minimizing environmental impact under the Protection of the Environment Operations Act 1997. Sustainable practice should be carried out throughout the whole process of manufacturing ranging from using green materials to efficiently disposing of waste. Using sustainable materials where possible is a great way to reduce the environmental impact.

Proposed control method

There are two available methods for controlling the brazing process. They are procedure and

automatic control. However, relying on operators to follow procedure consistently is unrealisticwhich brings us to automatic control. Automatic control is managing availability through acontrol system, either PLC's or relay logic.

The Relay System

Relay logic is robust in its simplicity. Being a reasonably cheap option however as the design

increases in complexity so does the number of components and the cost. Timers and counters

can also be quite expensive.

PLC 's minimise the number of components so you only have the essential relays. This reducesthe points of failure and overall cost. However it can be more expensive overall if you do notalready have the required programming software and requires specialised knowledge in itsconstruction. With a PLC you can also use smaller enclosures even with more complexprograms. Fault finding is reduced as there is easy indication of input and output operation.

The function of the control box required would be to monitor nitrogen flow rate and to turn offall 3 gases if the nitrogen flow is out of tolerance by identifying when the flow is approximately10L\min. It will require 2 timers. One for a delay on startup, another to stop nuisance trippingsmooth any small spikes in the flow. The on\off and duration will all be controlled by a newversion of the SE Gas Saver which includes electric ignition and nitrogen control. Therefore a signal will be needed to be sent to the gas saver to turn it off when there is insufficient gas and hold it out. A means of reseting the system is also required.

The PLC System

The PLC chosen for the control box is a Mitsubishi FX3S series as the software was already

purchased previously. Also being a cheap PLC at $180 it costs only a little more than a standardtimer. So it reduced the total cost of components eliminating the need for the 2 timers andmany relays in the control circuit.

After initial estimating of the number of I\O required. FX3S-10MT was selected. As with 6 inputsand 4 outputs, it has enough space available for the job. Also as it has 4000 steps ofprogramming available, much more then required. With a small size minimising enclosurerequirements. As the relay outputs are transistor outputs a interface relay is also required tocontrol the Gas Saver.

Flow Measurement

Selecting the correct type of flow measurement is important. There are many options but the

cost of conventional flow meters over 5l\min blows out going from $100 to $500 plus, alsorequiring an analogue input on the PLC or switched setpoints for a relay system furtherincreasing the expense. So a simpler option was chosen to install a proximity switch onto thepre-existing rotameters removing the need for a analogue input. Greatly reducing the systems cost.

Choice

With the number of relays and timers required for a relay logic circuit it makes sense to choose aPLC based system to replace them as it will end up being a cheaper option because of theminimised amount of control gear. Also it will require a smaller enclosure with many options toadd new features as the operators require them.

Change Braising Cells to a Production line.

After an initial site inspection by the owner with the maintenance team a task was created to change the layout of the production line to improve efficiency and reduce waste.

The outcome of this meeting was to change the work area from 8 workspaces laid out in a grid to 6 workspaces in the straight line connected via a conveyor system.

It is important for every company to reduce energy usage. Part of that is sourcing products sustainably if possible and recycling whatever they can. Reducing energy usage will help reduce the greenhouse effect slowing climate change.

Outline of the task

Advising a company on the environmentally efficient usage of energy in one of its manufacturing plants. As a case study, the most in-effiecient plant of the company will be chosen. The primary manufacturing process employed in the plant will be analysed for inefficiencies. Keeping in view the environmental sustainability factor, the energy efficiency of the primary manufacturing process shall be sought to be improved.

The company

Daikin is a Japanese multinational company having its global headquarters in the city of Osaka in Japan.The company was established in 1924 by Akira Yamada. In the beginning its name was Osaka Kinzoku Kogyosho LP. The name of the company was changed twice. In 1963 the first change of the company’s name was done to Daikin Kogyo Co Ltd. In 1982, the company was named to Daikin Industries Ltd which is the current name by which it is now known. The company is now a diversified conglomerate organized into six divisions which have their further sub-divisions in the form of departments. The six main divisions of the Daikin conglomerate are Air Conditioning, Air Filtration, Chemicals, Oil Hydraulics, Defence Systems, and Electronics.

The company in Australia

In 1969, Clark Daikin Australia Pty Ltd was established in Sydney. The company initially imported air-conditioning appliances from Japan and sold them in Australia. In 1980, the company changed its named to Daikin Australia Limited. The company established a manufacturing plant in Sydney in 1982.

My role

Identification of manufacturing process for improvement

After a review of energy use within the Sydney factory of the company, one of the areas identified for improvement was the brazing process. After analysis it was found there were a large number of defective units wasting energy, aluminium, copper and time.Therefore, in this report we are going to focus on how the company can improve energy utilization during the brazing process and increase its production capacity as well as save energy costs in the process.

Introduction to the Brazing process

Brazing is a process for joining metals. Along with soldering and welding it is the most popular metal joining process in the manufacturing industry. Like soldering, in brazing also, a filler metal is used to join two pieces of metal, unlike welding in which metals to be joined are heated and melted in a focused manner to create a joint.

Unlike in welding, the metals to be joined through soldering or brazing process are not heated to their melting point. The filler metal, therefore, has to be a metal whose melting point is lower than that of the metals to be joined.

The key difference between soldering and brazing is in the temperature at which the processes take place and their applications. In brazing process, the melting point of the filler metal used is usually above 450 degrees celsius and in soldering process, the melting point of the filler metal used is usually below 450 degrees celsius. Nowadays, brazing filler metals are usually alloys. Alloys have an added advantage of giving the joint more strength than an individual metal and are often lighter in weight as well, which reduces the stresses placed on the joint due to the solidified filler metal.

Brazing is used to join copper tubes and other metal components in the cooling equipment and air-conditioning industry because it provides a durable enough joint without the need of heating and melting the metal components to be joined. With the help of brazing, larger surface area components can be joined compared to welding as welding requires the two surfaces to be heated so that they can melt and join together. Welding large surface area therefore, requires focused melting of small locations throughout the joint surface along with the filler rods that provide extra metal to create the joint. The joint created in welding is of a permanent nature and not advisable in the case of removable parts because welded joints can only be broken apart and it is very tough to get a clean detachment if the need arises to replace one or more of the parts comprising the welded surfaces. On the other hand, the brazed surfaces can be comparatively easily and cleanly detached with the help of specialized tools in order to replace one or more of the components joined by brazing. This is the reason for the use of brazing process to join copper cooling rods used in coolant and refrigeration industry. Radiators Australia Limited is a company that manufactures cooling equipment. Therefore, brazing is the key process as well as the base process and the most used process by the company to manufacture its products.

Issues associated with the brazing process

Brazing is used for many industrial applications such as joining copper pipes in radiators and

refrigeration systems. But there is a big problem to stop oxidation on the parts being braised,NO2 is a useful inert gas commonly used to stop oxidation by pushing the oxygen out of the partbeing worked on. The issue is how to make the gas fully utilised.

Ten years ago, when the original systems were installed there were limited commercial optionsfor brazing control systems. The system currently installed was built inhouse and neveroperated to its expected potential ending up with many left bypassed. Causing a inefficient use

of gas creating more waste to ensure that the quality of work remains the same.

The quantities of gas used in a production line are not small, leaving significant room for thesystems improvement. A well managed gas flow is urgently needed. A well managed gas flow

can increase the quality of the final product by minimising oxidation on the copper. This can bedone by flow regulation, managing flow rates and availability of gases.

How brazing works-technical details

Brazing is a method of connecting copper parts by using a brazing torch. The gases used aregenerally, acetylene, LPG or Propane combine with oxygen to produce a flame withtemperatures above 450C. However, in this case LPG and Oxygen are used.The brazing process involves heating the copper tube where it is joined in a cup joint with onepiece of tube inside the other, then melting solder into the joint where it fills the empty spacehardening becoming a strong join.

However, brazing in this way can cause oxidisation inside the pipe where it was heated, seen asblack flaky ash and a discoloration of the copper surface. Commonly nitrogen is fed through thejoin as the brazing is taking place stopping the build up caused by the oxygen.

To summarise the actions of the brazer. The nitrogen hose is attached to the job to be worked

on. Following this,the brazing torch is lifted off its holder causing all 3 gasses used in theprocess to start flowing. The brazer ignites the torch off an automatic pilot flame then proceeds

to braze the copper joints. The brazing torch is then hung back up closing the valves for the LPGand oxygen. However, the nitrogen continues to flow for 10 seconds to increase job quality.

Current control method

For control of the brazing process, a SE Gas Saver is used.This device manages the LPG and

Oxygen when the brazing torch is lifted and replaced. It also has an automatic pilot flame toignite the torch, however it cannot manage the nitrogen flow by itself.

A separate control box manages nitrogen flow by using relays, a timer, a solenoid valve, and a

microswitch connected to the gas saver. It also manages the nitrogen flow rate by having theslug in a rotometer break a light beam.

Currently the nitrogen flow is set by the operator adjusting the rotameter. The gauge is out oftheir line of sight, so it is hard to notice whether the flow rate is correct.

The current system has a few failings. The gas used by the pilot flame doesn't produce anybenefit. If the nitrogen flow is unstable it can cause nuisance tripping. The trip is easily bypassedby removing 1 leg of the light beam sensor. There is a high number of components used givingmore opportunities for failure. The way the light beam sensor is connected to the rotometerleaves the fibreoptic leads unprotected, they can easily get caught damaging the rotometer.

Currently many of the relay boxes have been bypassed so the nitrogen flow solely relies on theoperator to check the flow rate which is not visible from their work stations. In some cases,requiring them to leave their torches lit for the 10 seconds to ensure nitrogen flow.

Task Planning

1.         Carry out risk assessment

2.         Identify Equipment needed for task

3.         Decide on a timeframe for the Task

4.         Identify related regulations

5.         Identify recyclable materials\energy wastage

6.         Source sustainable products

7.         Minimise waste where possible

8.         Review controls

9.         Review Schedule periodically

10.       Delays\Work interruption

11.       QC Checklist

12.       Finalise changes

13.       Store unneeded equipment

14.       Recycle Rubbish

15.       Sign off task complete

16.       Review Energy targets

1. Carry out risk assessment

Risk assessment to be carried out and then reviewed on site before the job can begin.

2. Identify Equipment needed for task

PPE Identified in the risk assessment are, Glasses, Long sleeve shirt, steel cap boots, long pants

Tools required

Handtools and an Electric forklift to move cells.

3. Decide on a timeframe for the Task

The timeframe to complete these works as discussed is 3 days over a weekend due to the fact that the area is fully utilized during the week.

4. Identify related regulations

Protection of the Environment Operations Act 1997.

AS/NZS ISO 14001:2016 Environmental management systems.

5. Identify recyclable materials\energy wastage

Energy wastage can be minimized by reducing waste of pipe and cabling, also using braising free pipe connections, also using electric forklifts for any lifting required.

6. Source sustainable products

Pipes and cabling to be sourced from an environmentally conscious and documented supplier.

7. Minimise waste where possible

Perform task efficiently while minimising waste, monitoring the work methods against the procedures. Referencing the environmental management plan.

8. Review controls

Review the risk assessment periodically during the job ensuring the controls are followed and that the environmental procedures are followed separating the waste.

9. Review Schedule periodically

Check project is on schedule and sustainability goals are being met.

10. Delays\Work interruption

Any delay or lack of parts to be escalated to the project manager promptly.

11.QC Checklist

Have a QC checklist filled out and signed by the installer on completion of the job.

12. Finalise changes

Ensure the work area is cleaned to the standard it was found in.

13.Store unneeded equipment

The 2 unneeded cells to be packaged on pallets and stored.

14.Recycle Rubbish

Copper and Aluminium to be recycled in their respective bins.

Cardboard and Plastics are to be compacted separately.

15.Sign off task complete

Complete lockout sheet,remove locks, and return equipment to service.

16. Review Energy targets

Create a periodic review for the process to ensure its overall efficiency continues to improve reducing energy usage.

Work instruction

Production line upgrade

Task

Change the layout of the production line improving the efficiency

Equipment\Tools

PPE, Glasses, Long sleeve shirt, steel cap boots, long pants

Forklift

Handtools

Method

1.         Isolate Gas and electricity to cells

2.         Check that there is no pressure and that electricity is off

3.         Disconnect electricity and pipes

4.         Arrange cells to new location

5.         Install new conveyor

6.         Reconnect pipes and electricity

7.         Clean work area\Store tools and equipment

8.         Deisolate electricity and gas

9.         Check pressure and function.

Referenced Documents

AS/NZS ISO 14001:2016 Environmental management systems

Work Schedule

Friday

1.         Review plan

2.         Ensure all equipment ready as per work instruction

Saturday

3.         Review risk assessment to identify new hazards

4.         Implement any new controls required

5.         Carry out work as per Work Instruction

Sunday

6.         Check that area has been cleaned correctly, identify and recycle waste correctly

7.         Check area is clear and all tools and spare parts stored correctly

8.         Perform QC on all changes, test function and installation quality

9.         Rectify issues and sign off job as complete

10.       Conduct a toolbox talk to review the job procedures and problems.

Conclusion

Improving the design of the control system has reduced gas use by over 5% which provides a

genuine reduction in operating costs every year. With the correct use of nitrogen also increasing

job quality and reducing the number of parts that fail QA testing. It's not just reducing the cost

but also increasing the overall efficiency of the factory. The number of defective units has also gone down due to the cycle.