market prices for several cranes

The following lists some of the available cranes on the market (curtesy of www.amazon.com), in order to assist the finance officer with rough prices we are likely to be selling our crane for:

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.

Hoist types and costs

Research was carried out into the type of winch or hoists that would be used and the possibility of using a travel trolley.

The following manual hoists were initially researched and the following information obtained from the site (http://www.hoistsdirect.com/):



The following information was obtained for powered hoists from (http://www.hoistsdirect.com/):



As these prices are far too expensive for the type of budget in question as well as having too high a mass to be used for this type of project, it was considered to buy the trolley component and winch/hoist components as separate items (http://www.keyonline.co.uk):

The following link (http://www.keyonline.co.uk/manual_c_Main006004001.html) lists some of the possible manual hoist options.

Further details are found in their catalogue page (http://static.manutangroup.com/KEY/en_GB/PDF/281.pdf)

The most popular including:



An alternative including the use of electronic winches, from catalogue (http://static.manutangroup.com/KEY/en_GB/PDF/285.pdf):




The electric winch would prove advantageous as it would lift a load more rapidly than a manual hoist. However it is far more costly and may be unnecessary for the situation at hand as it would be acceptable for the manual hoist to lift the item several cm from the ground, enough not to be blocked by anything in its path but low enough for safety reasons of the workers.

Out of the two manual hoists the best suited would be the Manual Hoist. The reasons are purely safety and convenience, as the Ratchet Lever Hoist would require more effort from the workers and closer contact to the load increasing safety risks while the manual hoist can be operated at a greater distance:

http://www.e-rackonline.com/product_images/1210.jpg

The next thing which would need to be considered is the trolley system which would allow the hoist to “hook” onto (http://static.manutangroup.com/KEY/en_GB/PDF/280.pdf):



Respectively each has their own advantages and disadvantages, which would need to be individually considered.

The masses of the combined system are lowered in the following manner:
manual hoist (11.7 kg) + push travel trolleys (9-16kg) =total mass range (20.7-27.7 kg)
manual hoist (11.7 kg) + geared travel trolleys (11.2-18kg) =total mass range (22.9-29.7 kg)

The Geared travel trolley is more expensive but provides more control when moving the load. The push travel trolley would need more support however it costs less and the following design could be looked into in order to avoid certain problems:



The beam width section is also important to consider as it will influence the type of I beam that can be used. The beam width most applicable would need to be in the range 50-220mm to be able to use these trolleys.

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.