Project Crane - Group E

After compiling all the research work and calculations done by us in this blog, I can conclude that our crane emerges as one of the most unique, effective and high performance cranes and fulfills all the requirements as specified in the tender proposal.

Some main features include:

· Unique and Simple design

· Ease of use

· Manual and Electrical Winch for easy usage

· Competitive price than other groups

· Discount available on big orders as mentioned by finance manager

· Easily assembles/disassembles in a Land Rover

· Extremely Light weight material used i.e. Aluminum 7075

At the end, I would like to conclude that this group work was very interesting for me because I had a chance to work as a team with my fellow class mates and all of us were very devoted to this work. All of us regularly attended meetings although we had too much work load but still we tried our best. Although, one member of the group did not turned up but still we divided the work load equally and discussed the mistakes and then made improvements in our crane.

As the last words, I say that you won’t be disappointed if u buy the cranes for us and we will try our best to serve you and the victims of the disaster relief areas.

Based on the presentations we heard and in comparison to our presentation, I can say that our presentation as well as our crane lacked some features that other groups had in them. The main thing was the stress analysis which our group lacked due to unprofessional behavior of our stress analyst. In simple words, he did not turn up in any meeting. So we had to do it in short time.

On the positive end, our presentation was quite well and our crane design and features were quite unique as compared to other groups. So overall, the presentation day was quite good but we could have done better.

Based on the presentations given and heard by our group and other groups, we have been able to access our mistakes both on the building of the crane as a whole and its manufacturing processes. We have decided to take in depth review on our stress analysis, crane balancing and other factor we were unable to complete in due time. On a positive note, we noticed our price range was reasonably good both when sold individually and in bulk based on our 40% wholesale discount. We also left room open to any future developments, adjustments and attachments to our crane to make it suitable for disasters and flood scenarios and in the future, more research would even be made on the production of a more smaller model to do a similar or even bigger job. This would enable the carrying, assembling and dismantling easier which was a major consideration in our quest to achieve and build this model. We expect any feedbacks to be related to us directly and we would get all adjustments sorted out as soon as possible. Thank you.

From the crane analysis, it can be seen that stress is applied on the upper beam and forces are acting from the centre of the beam, the load attached at the end and the weight of the winch. The diagram shows the forces acting on the beam and also modelling the vertical support as just a support and no force coming from there, the force acting vertically from the hydraulic actuator can then be determined in order to know how much force it would take to lift the beam with all the forces acting on it present assuming the weight of the beam is 200kg, the weight of the load is about 1000kg and the weight of the winch is 6kg. All these forces have been multiplied by 9.81 i.e. approximately 10 in order to find their forces due to gravitational effect and the moment has been calculated. The height of lift is also taken into consideration and regardless of the height, a formular has been put in place to determine the lift force.

As a company, we would be looking at making a 35% profit on each crane supplied. If bulk orders were to be placed, we would be able to supply the cranes at a cheaper per unit cost, but will also be able to buy them cheeper.

if a 100 units were ordered; the retail price of each crane would be £585.90
therefore 100 units = £5,859.

these prices are excluding any shipping/duty taxes associated. 35% profit is resonable to both parties as £585.90 is much cheaper than any of the 'competitors' cranes, including a certain crane made from wood?

For countries prone to natural disasters and devolping ecconomies, our product is the best suited for them as the reliability and practicality, are not sacrificed over afordability.

As told in the previous post, the material chosen is Aluminum 7075 due to various properties discussed before but now I will show a brief comparison of it with Steel and other form of aluminum.

Aluminum 7075	Steel
Specific Density 2.81g/cc	Specific Density 7.80g/cc
Price 0.93US$/lb	Price 0.59US$/lb
Ultimate Tensile Stress 275MPa	Ultimate Tensile Stress 558MPa
Young’s Modulus 72GPa	Young’s Modulus 190GPa

As seen from the table, the Young`s Modulus of Steel is very high than Aluminum 7075. But apart from this, it is very much lighter than Steel and due to this, it is suitable to be used in emergency situations.

Aluminum 7075	Aluminum 6061
Specific Density 2.81g/cc	Specific Density 2.75g/cc
Price 0.93US$/lb	Price 0.88US$/lb
Yield Strength 146MPa	Yield Strength 62 MPa
Young’s Modulus 72GPa	Young’s Modulus 65GPa

As seen from the table, the Specific Density of Aluminum 6061 and price is less than Aluminum 7075 but the Yield Strength is very much lower of Aluminum 6061 so one cannot use it for the crane design.

Therefore, due to convenient price, high tensile stress and less density we decided to use Aluminum 7075-T6 as our final material.