Professional Hours Work Report PDF

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Scott Johnston - 58055956 Mechanical Engineering Second Pro University of Canterbury Mechanical Engineering, Second Pro Professional Engineering Placement, Written Report Name Scott Johnston Student ID 58055956 Place of Employment Winstone Aggregates (GBCWinstone) Work Period 20/11/17 to 16/02/18 To...

Description

Scott Johnston - 58055956 Mechanical Engineering Second Pro

University of Canterbury Mechanical Engineering, Second Pro Professional Engineering Placement, Written Report Name Scott Johnston

Student ID 58055956

Place of Employment Winstone Aggregates (GBCWinstone)

Work Period 20/11/17 to 16/02/18

Total Hours Worked 369.5

Word Count 3824

Date 04/04/2018

Table of Contents 1.

Introduction.....................................................................................................................2

2.

Company Structure/Products Services.............................................................................3 2.1 Organisation and Products...........................................................................................................3 2.1.1 Aggregates.................................................................................................................................3 2.1.2 Sand..........................................................................................................................................3 2.1.3 Cleanfill.....................................................................................................................................3 Other Services....................................................................................................................................3 2.2 Major Technical Processes............................................................................................................4 2.2.1 Blasting......................................................................................................................................4 2.2.2 Excavating, Digging & Transporting...........................................................................................4 2.2.3 Crushing.....................................................................................................................................4 2.2.4 Screening & Cleaning.................................................................................................................5 2.3 Departments Worked In...............................................................................................................5

3.

Staffing issues and management......................................................................................7 3.1 Organisation Structure.................................................................................................................7 3.2 Personnel and Industrial Relations...............................................................................................8 3.3 Health and Safety.........................................................................................................................8

4.

Work Performed..............................................................................................................9 4.1 MEX Trial....................................................................................................................................10 4.1.1 Familiarisation.........................................................................................................................10 4.1.2 Asset Register..........................................................................................................................10 4.1.3 Communication.......................................................................................................................11 4.1.4 Setting up MEX........................................................................................................................11 4.1.5 Trial.......................................................................................................................................... 11 4.1.6 Feasibility Report.....................................................................................................................12 4.1.7 Presentation............................................................................................................................12 4.1.8 Conclusion...............................................................................................................................13 4.2 Asset Care Plan...........................................................................................................................13 4.2.1 Risk Matrix...............................................................................................................................13 4.2.2 Procedures...............................................................................................................................13 4.2.3 Faults....................................................................................................................................... 13 4.2.4 Maintenance...........................................................................................................................14 4.2.5 Annual Cost Estimate..............................................................................................................14 4.3 Additional Work Performed........................................................................................................15

5.

Conclusion.....................................................................................................................16

6.

References.....................................................................................................................16

1.Introduction This report covers the professional work performed by a Mechanical Engineering student over the summer of 2017/18 working for Winstone Aggregates, based at Hunua Quarry on the rural outskirts of South Auckland. This report investigates the structure, products and services of the company as well as the work performed by the student. This also looks into the company’s issues, and the relevance of the work performed and the University of Canterbury Mechanical Engineering degree are explored.

2.Company Structure/Products Services 2.1 Organisation and Products The organisation was Winstone Aggregates, they have various quarries spread around New Zealand. Hunua Quarry is located at 489 Hunua Road, Hunua, Auckland. The major products that are exported from the quarry include aggregates, sand, and cleanfill. These are either transported via trucks or sold directly from the quarry. A brief rundown of the products can be seen below:

2.1.1 Aggregates Aggregate is rock which has been crushed and screened to a certain size and quality. Various GAP products are sold ranging from GAP7 through to GAP100. GAP stands for ‘General All Passing’, this means all of the rocks pass through a screening process of a particular size which determines the number that lies after the ‘GAP’.

2.1.2 Sand Various types of sand are sold, these include Concrete Sand, Block Sand, General Purpose Sand and Fill Sand. The name before each of the sands gives an indication of what that type of sand is used for, for example, Concrete Sand is primarily used in the manufacture of concrete.

2.1.3 Cleanfill Cleanfill is materials that, when buried, will have no adverse effect on people or the environment [CITATION Wai151 \l 1033 ]. They include virgin natural materials such as clay, soil and rock, and other inert materials such as concrete or brick. Winstone Aggregates operates cleanfill

sites in a number of easily accessible, well-situated locations around New Zealand. They have a specific management plan, covering all aspects of operation and management for each site, including: 

Resource consent requirements



Cleanfill design



Waste acceptance controls and procedures



Daily operating procedures



Environmental controls and monitoring

Other Services Winstone Aggregates also provide commercial testing services in five IANZ laboratories (International Accreditation New Zealand) throughout the country. These services include: 

Field density



Dynamic cone penetrometer



Shear strength



Impact hammer



Sieve analysis



Plasticity index



NZ Standard / Heavy / Vibratory and Australian modified compactions.

2.2 Major Technical Processes There are four major technical processes that must be carried out in order to convert rock in the ground to a premium sized aggregate ready to be transported away for use. 2.2.1 Blasting The first major technical process is blasting which is carried out in order to break up a rock face making it easier to transport and crush the rock. The process begins with an explosives engineer coming to 3D map the face in which they intend on blasting. This allows the engineer to accurately figure out where to drill the shot holes in order for the blast to be carried out safely and efficiently. The amount of explosive used, depth and location of the shot holes depicts the

size of rock fragments that are produced as a result of the blast. This is important to get right as it saves a lot of time in the long run if it is. 2.2.2 Excavating, Digging & Transporting After the blast, the rock must be moved to the fixed crushing plant in order to be crushed. Loose rock not fully broken from the face is excavated using an excavator. A digger starts loading dump trucks in order to transport this rock away to the fixed crushing plant. 2.2.3 Crushing Dump trucks feed the rock into a hopper at the fixed crushing plant. The rock is then sent through three crushers to break the rock down into smaller pieces. This includes one jaw crusher and two cone crushers. The jaw crusher consists of one heavy metal plate which moves backwards and forwards against a fixed plate, this motion crushes the rock which then falls out the bottom of the crusher onto the cone crushers. The exit of the jaw crusher is smaller than the entry. The cone crushers break rock by squeezing it between a mantle and the crusher wall. A steel mantle is mounted on an eccentric bearing, hence rotating off centre and crushing the rock as shown in Figure 1. Rock is fed in the top of the crusher and falls out the bottom once it has been crushed enough to fall through the gap between the mantle and the wall. The rock is then sent through a VSI (Vertical Shaft Impactor) where it’s sharp edges are smoothened out and shaped. The VSI houses an impeller rotating at high speed which displaces the rocks against the walls of the VSI and against each other, hence shaping them. Conveyors are responsible for transporting the rock to each of the different processes.

Figure 1: Animations of the processes undertaken by the Cone Crusher (left), [ CITATION Nor12 \l 1033 ], and Jaw Crusher (right), [ CITATION You13 \l 1033 ]. 2.2.4 Screening & Cleaning During each stage of crushing, the rocks get progressively smaller. The sizes of these rocks vary immensely, hence screening processes are required in order to filter them into size groups to be sold. Screens are mesh gratings, where the size of the hole differs depending on what size rock is required. Screen changes occur frequently depending on the pull from customers. Screens vibrate and have water poured over them in order to ensure that every piece of rock falls into the correct size grouping.

2.3 Departments Worked In Winstone Aggregates has quarries all throughout New Zealand. During my internship, I worked at Hunua Quarry in the outskirts of South Auckland. The quarry itself is divided into two plants, the fixed plant, and the mobile plant. The fixed plant refers to the assets present in the process of crushing rock, this includes:

Table 1: Brief description of the assets present in the fixed plant.

Asset

Brief Description

Crushers

Crush the rock into smaller pieces

Barmac

Shapes the sharp edges of the rock

Conveyors

Transport the rock

Feeders

Feeds rock into the crusher at an optimal rate

Scrubber

Washes silt/dirt/clay off the rocks

Screens

Sorts rock into different sizes

Bins

Store the rock

Whereas the mobile plant refers to the machines involved in the process of collecting the loose rock from the pit and transporting it to the fixed plant. These machines include diggers, excavators, and dump trucks. Another addition to the mobile plant is brought upon by the environment. Dust is a huge issue and water carts (part of the mobile plant) are used to water the roads hence preventing the dust, this issue is only really present in summer. During the first week, I spent time getting experience in each of the plants, but after that, all of my time was spent in the fixed plant where I carried out my MEX maintenance software trial. The fixed plant is used to produce different size and grade aggregates from rock that is fed into it. It is monitored by six workers who rotate various jobs, these jobs include monitoring the feed rates and the condition of each of the machines in the control room, walking around the plant to check the machines, carrying out visual inspections and entering data into MEX when it is implemented. Currently the work is scheduled and controlled using hand written calendars and notes spread around the control room, this is untidy and a reason for MEX to be brought in as MEX puts all the work into one maintenance calendar. The equipment used in the department involves a lot of heavy machinery which can be seen Table 1 above. The equipment is laid out in a large building seen in Figure 2 below. It is in order of sequence in which the rock passes through each machine.

Figure 2: Shows the fixed plant from the outside, with four bins on the left ready to load aggregate into trucks for export.

3.Staffing issues and management 3.1 Organisation Structure Winstone Aggregates was founded in 1864 by William Winstone when he first started selling coal from a sole horse and cart. Since then GBCWinstone has been formed, combining Winstone Aggregates, Winstone Transport, and Golden Bay Cement. Winstone Aggregates comprises of 31 quarries nationwide. In my time working with them I visited 3 of those quarries (Hunua, Pukekawa, and Yaldhurst) and was placed at Hunua for the majority of my summer internship. I worked under Matt George who is the asset manager for GBC Winstone along with another engineering intern. The majority of my internship was spent at Hunua Quarry where the quarry manager is Ben Hawkins. Matt and Ben both work under Ian Jones who is the CEO of GBC Winstone. Ian works under Ross Taylor is the CEO of Fletcher Building. At Hunua Quarry there are 8 employees working in the office, they make up the management for the quarry. These include the quarry manager, engineer, plant supervisors, and administrators. They are tasked with supervising the 40 operators and drivers that handle various pieces of machinery around the

quarry. This machinery includes dump trucks, water trucks, diggers, excavators, loaders and mobile crushers. Ross Taylor (CEO Fletcher Buidling)

Ian Jones (CEO GBCWinstone)

Matt George (Asset Manager GBCWinstone)

Ben Hawkins (Hunua Quarry Manager GBCWinstone)

Engineering Interns

Management at Hunua Quarry

Operators & Drivers at Hunua Quarry

Figure 3: Shows the structure and ‘who is the boss of who’ of the wider company.

3.2 Personnel and Industrial Relations It appeared that dealing with people was over half the job for the office workers at Hunua Quarry. Firm but friendly orders were given to keep them in line. Aside from the occasional argument between operators, everything was kept relatively smooth. Operators who didn’t get on well with each other were put on separate shifts or organized such so they didn’t have to see much of each other. Even though some operators/drivers worked a lot harder than others and did much more efficient and effective jobs, the pay had to be consistent across all of the workers in order to prevent any disputes. Operators despise being called drivers and there seems to be a clear hierarchy amongst the workers as to who can operate how many machines and who is limited to just driving dump trucks. This isn’t an ideal environment to have in the workplace, although it is difficult to control this.

3.3 Health and Safety GBCWinstone (and Fletcher Building) has an exceptional health and safety program in which they run and pride themselves in. When a new employee, contractor or visitor reports to the office at one of the quarries around New Zealand, they are required to undertake an induction before being allowed entry into the quarry. This induction involves a senior member of the team running through all the potential hazards present at the site and the processes and procedures in place to avoid them. An additional rule implemented states that every employee is expected to report a minimum of one hazard each month. GBCWinstone also ensures that all of their employees are trained first aiders, this adds to the safety of the workplace. The first two days of my internship were spent being inducted into Fletcher Building, this involved presentations from various different workers running through all the possible situations that could arise and everything that could go wrong and ways in which to counter this. An example of a common safety procedure is shown below in Figure 4 and is known as the lockout procedure used to lockout a piece of equipment so there is no chance it can start when work is being carried out on it. Everyone involved in the work being carried out places their lock on a box which in turn locks the master key, therefore it is impossible for the machine to start while people are working on it.

Figure 4: The lockout procedure performed when carrying out work on a piece of equipment.

4.Work Performed Throughout my internship at GBCWinstone, I was tasked with two main projects. My first project was to trial a preventative maintenance software for GBCWinstone and carry out a feasibility study to determine whether it was a good fit for the company. My second was to formulate an asset care plan for the seven Metso High Performance Cone Crushers currently being used throughout quarries in New Zealand. These tasks required several techniques in order to carry out. The 2nd pro design papers ENME301 and ENME311 were helpful as I employed report writing techniques learned in this course when formulating the feasibility report and the asset care plan.

It is very difficult to criticise Winstone Aggregates with their professionalism around Health & Safety and most areas, but I was amazed that they did not have anything in place to keep records on what was going on in their fixed crushing plant. Contractors come in to do maintenance on it at 2 am in the morning and there is no record of what is happening in there. This is not an issue now that MEX has been implemented, but it was a big issue before that. This was one of the main reasons that MEX has since been introduced.

4.1 MEX Trial I was tasked with trialing a preventative maintenance software for Hunua Quarry. This software was known as MEX. This trial was to be undertaken on the fixed crushing plant at the quarry. The work I undertook to achieve this trial, and produce and present the feasibility report, is chronologically broken up into the processes shown below.

4.1.1 Familiarisation My first week on site was spent getting to know the quarry. This involved going around with different workers and experiencing first-hand what their average day in the quarry looked like, their main objective, and the importance of it to the company. T...