Manufacturing costs

Manufacturing Cost
According to 'Swift, K.G. & Booker, J.D. , Process selection: From design to manufacture', the Manufacturing cost = material cost + processing cost.
This can be spit up further, processing cost consisting of basic processing cost multiplied by the relative cost coefficient. Hence the new equation will be: Manufacturing cost = material cost + (Basic Processing cost*Relative Cost Coefficient).

Relative Cost Coefficient
The equation for the Relative Cost Coefficient is : Rc = Cmp.Cc.Cs.Ctf, where:

'Cmp' is the material process suitability
'Cc' is the component geometry
'Cs' is the size, thickness consideration
'Ctf' is the tolerance/surface finish

All of these unknowns should already be held available by the design team except for the 'Cmp'.
The 'Cmp' is dependant on the process used to manufacture and can be found from the 'From design to manufacture' book.
Hence the new equation will be Manufacturing cost = material cost + (Basic Processing cost*(Cmp.Cc.Cs.Ctf))

References:
'Swift, K.G. & Booker, J.D. , Process selection: From design to manufacture'.

Abdi - Finance (Suppliers)

Abdi Elmi - IPE160

From calculations we’ve done we found that the most suitable beam is the IPE160. Using its properties the IPE160 is ideal with the beam length to be 4.7m. Researching the web, the cost for this type of beam is very vague due to the fact that you have to contact the suppliers (mostly living in east-Asia) for a ‘negotiable’ price. One example of these sorts of websites is: ecplaza.net/tradeleads/seller/6010942/ipe140ipe160_ipe180_ipe200.html. This is a problem that we need to discuss in our next meeting.

There are three structural steel types that I’ve been researching on the net. The steel grade S274, S355 and S460. Almost all UK structural steels are the S275 and the S355. The letters and numbers are:

(S) Structural and (three digit numbers)Yield Strength (Newton/mm squared)

Here’s a table I’ve constructed of each steel grade’s properties:

Steel grade	Yield-min (MPa)	Tensile-max (MPa)
S275	275	580
S355	355	680
S460	460	670

One task that i'll have to do is find the prices for these steel grades and see which one is most suitable for our particular crane.

Abdi Elmi - Finance

Since we were quite fond on the idea of Aluminium alloys ive been searching the net for their industrial prices. I came across a real good website :
http://www.metalprices.com/FreeSite/metals/al/al.asp

It shows how much the current Aluminium alloys are sold in the stock market in a range of different currencies. It's got this Aluminium alloys calculator which lets you choose an alloy, showing it's prices per Kg or lb.
The alloy calculator link is :

http://www.metalprices.com/freesite/alloycalculator/AlloyPlus.aspx

A problem I stumbled across is that the alloys were all named using unique identity numbers, so it's hard to tell which alloy has what metal inside it. It's crucial for our stress analysis to find the yield stress and it's young modulus so we have to distinguish one alloy from the other. Here's a list of the alloys:

226(GBD - AlSi9Cu3)
319 , 319.1
356.1
535.2
A356.2 ,
A380 , A380.1 (LME Al Alloy)
A431.1
B390.1
D12S (JIS H2118-1976)

We need to research each alloy and compare their advantages and disadvantages to make it suitable for our crane build.

Abdi Elmi - Initial Crane and Finance research

Crane Research

Through net research ive found quite a few portable cranes that are manufactured and mass produced by companies such as : Abus Cranes , Spanco Inc, Contrx Cranes etc.
The most ideal crane most of these companies supply is the Jib crane:From our first few meetings we've identified flaws to this design in out particular situation (such as the platform and the mobility) and we're planning to go for quite a different design.

Finance

Ive done some research on manufacturing finance (via previous lecture notes). Some equations essential to finding the manufacturing cost of the crane parts is shown below :
Manufacturing Cost(Mi) = Material Cost(Mc) +( Processing Cost(Pc) * Cost Coefficient(Rc))
[Mi=Mc+(Pc.Rc)]

Material Cost(Mc) = Total volume of material to produced part(v) * Cost of material per unit volume (cmt)
[Mc=V.Cmt]

The material we discussed so far in using is an Aluminium alloy, but that ofcourse is subject to change.
Manufacturing costs will alter depending on the method of manufacturing and the individual shape complexity, but that will be something we will discuss in the near future.