Steel Rope.

As there is a winch system within our crane, we shall have to use a strong type of steel rope, to hoist our load. We have previously stated we shall be using stainless steel. As it is a 'rope' we cannot just buy steel in a rope form. Instead, to achieve these desired results, a special blend of steel is produced, giving it strength, and ductility. When this is made, several of these rolls, or strands, are woven together, around a typically steel core, to produce one large 'rope'. By doing this, it enables the user to have extra support.

Ropes are favoured now due to chains. This is due to the fact they have a higher reliabililty compared to metal chains. Flaws in chains can lead to disaster, i.e. a dropping of the load. With wires however, the flaws do not make much of an impact.
The flexibililty of the rope is critical in our crane. The rope can then be wound around a cylindrical barrel, to lift a load, and unwound to put down a load.






















Above, we can see the wires, which are bonded together to form a strand, which is wound together with other strands to form the rope.

Cable materials

Crane Idea Sketches

Drawing(simple sketch)

A little inspiration...!

http://www.youtube.com/watch?v=pqSFxZV6OvY&feature=related

Initial Designs

Crane Design
Conditions we are considering:
1. To be able to be carried manually
2. Fit the crane in back of a 4 x 4
3. Ability to be assembled
4. Can be hand powered or motor powered

As decided in our last meeting, I designed my initial ideas for a crane that follows the conditions.
There is a potential problem that could occur if these designs were placed straight into the disaster areas. I am currently working on ideas on how to secure the base of the crane i.e. with wheels or fixed. In all situations they are designed to work on level ground. This will need to be considered in the design. Also the balance of the crane needs to considered as it will be used in disaster conditions.

We will update more after our next meeting on our detailed designs....

Crane Specification

The crane specification:

- Be able to lift loads of not less than 1000kg.
- Transport the load not less than 4m from the point of lift.
- Be able to be disassembled and carried manually over 100m of rough ground.
- Be able to be carried by a standard Land Rover size 4x4.

Initial research

Safe working distance from power lines
* when the operating near high-voltage power line *
normal voltage(phase to phase) / minimum required clearance

upto 50kV / 10ft(3.1m)
50 - 200kV / 15ft(4.6m)
over200 - 350kV / 20ft(6.1m)
over300- 500kV / 25ft(7.6m)
over500 - 750kV / 35ft(10.7m)
over750 - 1000kV / 45ft(13.7m)

*while the transist with no boom and load or mast lowered)

normal voltage(phase to phase) / minimum required clearance

upto 0.75kV / 4ft(1.2m)
0.75 - 50kV / 6ft(1.8m)
over50 - 345kV / 10ft(3.1m)
over345- 750kV / 16ft(4.9m)
over750 - 1000kV / 20ft(6.1m)

General Research on Cranes

A crane can also be defined as a tower or derrick that is equipped with cables/ropes and pulleys used to lift and lower heavy materials. Cranes are commonly used in the construction and manufacturing industry of heavy equipment.
Cranes are driven by different means namely by electrical power (motor), steam, hydraulics or even manually (hand power).

I have been doing some research on various types of cranes and it appears there two main forms:

1) Mobile Cranes – these usually take the form of a telescopic boom mounted on a mobile platform i.e. rail, water or wheels. These cranes have the advantage of flexibility and mobility which allows easy transportation from one location to another. Examples include:

Truck-mounted crane


Crawler crane

Floating crane

2) Fixed Cranes – sacrifice mobility in exchange for the ability to lift and move greater loads, this is because they have greater stability and can reach far heights. While these cranes are not meant to be moved, some can be disassembled and reassembled for added mobility. Examples include:

Tower crane


Jib crane


My next post will show sketches of my crane idea, which has to meet the design specification for the invitation to tender.

Crane Research and Possible attributes to adopt for the Model

What are Cranes?
A crane is a lifting machine, generally equipped with a winder (also called a wire rope drum), wire ropes or chains and sheaves that can be used both to lift and lower materials and to move them horizontally. It uses one or more simple machines to create mechanical advantage and thus move loads beyond the normal capability of a human (in this case more than 1000kg).

So to get ideas of what sort of an ideal crane to model we will look at different types of mobility cranes.

 Truck-mounted cranes: these are cranes mounted on trucks. This eliminates special needs for the crane to be transported by special equipment. Can lift loads ranging from 14.5 tonnes to 1300 tonnes.
 Side lift cranes: A side lifter crane is a road-going truck or semi-trailer, able to hoist and transport ISO standard containers. Container lift is done with parallel crane-like hoists, which can lift a container from the ground or from a railway vehicle.
 Rough terrain cranes: A crane mounted on an undercarriage with four rubber tires that is designed for pick-and-carry operations and for off-road and "rough terrain" applications. Outriggers are used to level and stabilize the crane for hoisting. Load range is normally about 70 tonnes.
 All terrain cranes: A mobile crane with the necessary equipment to travel at speed on public roads, and on rough terrain at the job site using all-wheel and crab steering. This is a classic model combination of good manoeuvrability along rough grounds and good mobility on roads.
 Crawler cranes: A crawler is a crane mounted on an undercarriage with a set of tracks (also called crawlers) that provide stability and mobility. Crawler cranes range in lifting capacity from about 40 tonnes to 3500 tonnes. However, because of the crawlers and crane, the machinery is very heavy and this comes as a disadvantage due to its limitation in movement and would have to be disassembled if in need of working at other job sites.

After looking at all these different types of cranes, we can say that we can take the best attributes from all these and model a smaller and portable crane capable of delivering to the recommended specifications.

Good attributes from all these cranes will include:

• The ability to move around on site and perform each lift with little set-up, since the crane is stable on its tracks with no outriggers. In addition, a crawler crane is capable of travelling with a load (crawler cranes).
• Able to travel on main roads and highways. This additional flexibility makes it possible to transport large loads and access a wide range of locations (All terrain cranes)
• Quick and easy mobility on roads and not slowed down cranes mounted on the trucks (Truck- mounted cranes and side lift cranes).
• Have outriggers which help provide stability when lift or hoisting loads (side lift cranes).
• Spotters are used to ensure that the load to be lifted is properly installed.

More concept Design

Group H Project Plan Schedule

8^th March 2010

- First group meeting - review project briefing

- Discussion of roles

11^th to 18^th March 2010

- Allocation of roles

- Start of individual research on cranes

- Sketch individual crane idea(s)

18^th March 2010

- Discussion and review of individual research on crane concept ideas

22^nd March 2010

- Group selection of crane concept

25^th March 2010

- Final group meeting before Easter holidays - discuss tasks to be done over the Easter break

25^th March to 19^th April 2010

- Start of in depth analysis of selected crane concept

- Compilation of full Financial Report - breaking down the cost of crane kit

- Web conferencing (Online group meetings)

19^th to 22^nd April 2010

- Review of work and addition of final touches

23^rd April 2010

- Closure of Tender proposal - submission of work

23^rd to 25^th April 2010

- Compilation of Tender Presentation

26^th April 2010

- Submission of Tender Presentation

26^th to 27^th April 2010

- Preparation for Tender Presentation

28^th April 2010

- Group delivery of Tendering Presentations (10mins Long)

Initial concept Design

Emergency Crane Project- Contractor Organisation

Team Roles:

Adam Rana,
Project Manager

Ilute Nyambe,
Finance Officer

Arnold Ngang,
Chief Designer

Park Jungkyoo,
Stress Analyst

Ravi Parmar,
Materials Specialist

Over the next few weeks, we're looking forward to work on the tender for the Emergency Crane, and designing a small portable crane capable of lifting loads of up to 1000kg. It should provide a huge advantage in the aid of disaster relief efforts.
As a team bidding for this tender, we will be meeting on regular basis on Mondays and Thursdays.
Stay tuned for next post on the early designs of the crane and research.