Crane Definition and 137 Threads

I recently saw a massive new crane at a ship-repair yard. Something like this one: What surprised me was that for such a massive construction the load limit said "only" 300 tons. I seem to recall much smaller road moving cranes (say Demag) with a 300 ton lifting capacity...

This crane is lifting a 1Kg Box.Gravity exerts 10N on this.The crane uses 11N on lifting the box-That means the box is accelerating at 1m/s2.This also means it travels more and more distance in one sec as it rise(because of acceleration).This means that the work done by lifting the box also...

Looking for a bit of help on finding some advantages and disadvantages of using this proposed stewart platform (cable) system (James Albus invention) on a tower crane. How would it improve load control? Would it genuinely stop the load from swaying? Would it allow for more accurate positioning...

Homework Statement A quarry crane is used to lift massive rocks from a quarry pit. Consider the simplified model of such a crane shown in the figure. (Figure 1) The ends of two poles are anchored to the ground at the same point (point O). From this point, one pole rises vertically and the...

Homework Statement need to calculate cantilever beam analysis, column analysis, pivot pin analysis, ram pins analysis the attached pdf has the picture of the crane i intend to use. Homework Equations Tensile stress, σ = F/A General bending equation: M/I = σ/y Moment of inertia...

Homework Statement You are a member of a medical forensics team investigating a fatal accident at a freight yard. A new crane for lifting cargo broke while lifting a package and the police suspect sabotage. The crane consists of 45.0 kg, 15 ft lightweight aluminum bar supported at its...

First of all, I'm sorry for my bad language. I'm dutch and not the best in English. I'm doing an internship on a compagny and I'm having problems with 1 equation. i know the basics but this one i can not solve. i will draw a simple design (think of a crane) it has 2 bars, the horizontal...

Hello and thank you for allowing me to post a question. I am not very familiar with systems engineering and have a question about the frame joints connecting the main body of the MSL (Mars Science Laboratory) powered descent stage with its 8 Aerojet MR-80B 800 lbs thrusters (1). I am...

Homework Statement A large tower crane is used to move heavy objects in a construction site. The crane uses a counter weight with a mass of mw = 1w.0 Mg (mega grams), and the top beam of the crane also has a mass of mc = 1x00.0 kg which is evenly distributed along the beam. The length of...

how do i determine the bending stresss on the vertical column?? i already have the bending stress on the horizontal member due to a load of 4000lbs..and i have the bucling st or compressive stress on the column.i was told that the column undegoes both compressive and bending stress.. is the...

]1. Homework Statement [/b] The problem is attached in the picture The Attempt at a Solution The free-body diagram is in the second picture. However, when I try to do 1)Sum of horizontal forces = 0 2)Sum of Vertical forces = 0 3)Moments about A, B, C, = 0 I get nonsensical...

Hello , I have a 60kW hoisting motor with 600 rpm ,10 pole ,crane duty slip ring motor When the motor is started for its hoisting operation through resistance motor starts slow and immediately goes into full rpm having no sign of resistance. Does anyone know what might be the reason...

How on Earth have these things not died out yet? There has been one flapping about my room all day, hitting into every wall/piece of furnature it can. It managed to lose a leg so it's going about with 5 which must have off balanced it or something because it can only seem to fly in helices...

hello guys, Do you have any sample project of Truck-mounted crane that contains drawing,calculations ? Best Regards

I need to figure the load on a knuckel boom for a idea I have . it is like the ones that are located on the frames of trucks right behind the cab to be able to unload the truck or trailer. This will be of a smaller stature. The arm would pivot in the middle and rotate. and use hydraulic...

im am a first year mech eng student. I am so lost on this question. the image is the diagram I am trying to solve. i think the compressive stress of the crane boom is what is confusing me. i don't want the answer, just where do i start? Force polygon? math? please tell me how you would solve...

Hi all, This might be considered a coursework question, insofar as I'm doing it as a student and not a professional, but it's less to do with homework type questions and more to do with software fiddling, so I thought I'd post it here. I apologize if it's not the right forum. I've been given...

Consider the following picture, where the same platform and man is being lifted by a crane and by the man standing the platform, who can pull on a rope connected to a pulley in the ceiling. My question is: Does the scenario in which the man has the pulley have a mechanical advantage over the...

Across the street from my apartment there is a building under construction and a large jib crane is right outside my window. Today we have 20-30mph winds. All construction workers have gone home for the day. I see that the crane is rotating back and forth. It's very unnerving, but as I read...

Please redirect if this post is not in the right place. I want to install a jib crane in my shop. Vertical upright is planned to be a 5" H-beam in concrete, with 12' above ground, 4' into rock below grade level. Horizontal beam will be same, 10' long. (See attached figure) Am trying...

Homework Statement The object is a crane arrangement of pipes that falls forward without any loads or counterweights on it. We can take it apart measure the weight and the length of the individual pieces.How much weight can a tower crane lift without tipping? I just need a general way to...

Hi there. I've got issues. Big ones. I need to simplify this crane structure, and calculate the strength on cilinder |c1c2| when applying a vertical load on the crane's hook. The purpose of this is to find how much of the strength is absorbed by the first cylinder (and possible the second one...

Homework Statement A crane has a maximum safe working load of 1.2 * 10^4 N and is used to lift a concrete block of mass 1000kg. What is the maximum safe upward acceleration of the block while being lifted? Homework Equations F=maThe Attempt at a Solution F=mα 1.2*10^4=1000*α α= 12m/s2The...

Homework Statement The boom in the figure below weighs 2600 N and is attached to a frictionless pivot at its lower end. It is not uniform; the distance of its center of gravity from the pivot is 35.0 % of its length. Homework Equations Find the tension in the guy wire. Find the...

I’ve been looking at this “Self leveling pallet fork” which is supposed to, as the name suggests, keep itself perfectly level regardless of the load applied. I guess I can see how it would adjust itself depending on the weight, but I just can’t wrap my head around how it can possibly adjust...

Gentlemen, I am needing help choosing the correct materials to construct a stationary 'A' frame crane with a fixed radius of 15ft, back stayed with 2-1" cables approx. 70ft behind main non-rotational boom legs attached to embedded concrete weights, height of boom is 60 ft with pendants...

Homework Statement The arm of a crane at a construction site is 15.0 m long, and it makes an angle of 15.8 with the horizontal. Assume that the max- imum load the crane can handle is limited by the amount of torque the load produces around the base of the arm. What maximum torque can...

Can someone explain to me why the torque due to tension is taking from the roller instead of at the end of the beam. If you were to take it from the end of the beam you would also need to take the torque created by the bending of the cable. This is obviously more complicated. It just...

I need to adjust the safety trip at 110% of the nominal load ( 130 tons ). This means that I need to load the overhead crane with 143 Tons. With this load on the floor I start to rise the load with the crane, but I measure less than those 143 Tons ( say 135 Tons). This means that we can never...

The problem bellow is a real problem and I would like to get some ideas in order to overcome it. As you can see in the attached doc, we have two winches ( drum 1 and 2 ) on the same shaft of motor M1, two moving pulleys ( 3 and 4 ) and a fixed pulley (5). The load is 130 Tons, and we can...

The problem bellow is a real problem and I would like to get some ideas in order to overcome it. As you can see in the attached doc, we have two winches ( drum 1 and 2 ) on the same shaft of motor M1, two moving pulleys ( 3 and 4 ) and a fixed pulley (5). The load is 130 Tons, and we can...

As you can see in the attached doc, we have two winches on the same shaft of motor M1, two moving pulleys ( 3 and 4 ) and a fixed pulley (5). The load is 130 Tons, and we can measure that with a load cell at pulley 5 ( 32,5 Tons) when we stop the lifting of the load. But when the load is...

crane: http://tinypic.com/view.php?pic=2ywiidh&s=7 Lifting: http://tinypic.com/view.php?pic=309ok06&s=7 Determine the length of each chain sling that will hold the transformer, if the safe working load in each sling is not to exceed 150 kN. (H3.1) Calculate the maximum stretch in the...

To calculate the height of a crane which is on top of a building, dennis measures the angle of elevation to the bottom and the top of the crane. these were 62 degrees and 68 degrees respectively. if the building is 42 metres high find the height of the crane. I'm asking for a friend, excuse...

To calculate the height of a crane which is on top of a building, dennis measures the angle of elevation to the bottom and the top of the crane. these were 62 degrees and 68 degrees respectively. if the building is 42 metres high find the height of the crane. I'm asking for a friend, excuse the...

Homework Statement prime mover = 220 hp crane = 2000 tonne velocity crane = 10m/min = 0.17m/sec acceleration crane = 0.017m/sec every 100 tonne = 6 tonne of friction 1hp = 726 W 1 tonne = 1000 kg Homework Equations how many prime mover are needed to pull the crane?prime...

Homework Statement An object of weight 8526 N hangs at an angle of 5.0° when the crane’s trolley at point P moves to the right with constant acceleration, as shown in the diagram. Calculate the acceleration of the trolley and load. Homework Equations 9.8 / tan (90-5) = 0.857 m/s^2...

I am working on a 3D crane system, the system has three dc motors for y, x and z axis, and i control them with a PWM signal. i need to find the relationship between pwm and torque or torque and duty. could someone help me, thanks

Hi for my design project at uni I am to design a truss crane to a certain spec. I can easily calculate the forces in a truss without the pulley systems. However when I have the pulleys I'm not sure how this affects the forces in the truss. I have the load attached via a 4 cable pulley at the...

crane sling tension... Here i am stucked with some problems in physics.could you please help me to solve the below problem from the photo of the tower crane,if the crane is to lift a concrete slab with dimension of 250mm,3400mm,6000mm calculate the. 1.load in kN that thecrane...

Homework Statement 1)Derive equation of motion for trolley. 2)Derive the equation of motion for the load using balance of torques. 3)Then relate the force applied to the angular displacement of the load. Coefficient of friction between trolley and rail is negligible. For the moment of...

Homework Statement Hey all, I'm stuck on some homework and any help would be awesome. this is the question The crane shown in the diagram must carry a load of 600 lbs, at a distance, shown in the figure, of 20 feet from the center of gravity of the crane. If the crane weighs 1,500 lbs...

As part of my studies in college I've been given a project to design a crane which can lift 10 tonnes 20m in less then 60 seconds and I've done a lot of the calculations for the motors etc. However I was just wondering if anyone could advise me would it be possible to do this without using...

Hi, the problem states; A crane of mass 30,000kg is secured to the end of a steel plate 6 m long. At each end of the plate are a set of wheels. The crane has a jib of length 15m and is required to lift a mass of 25,000kgs from the end of the jib. The jib is positioned over the 6m long steel...

Hi, Homework Statement I'm designing a C++ program to simulate the operation of a steel processing warehouse. Part of my code requires me to calculate the time it takes for a crane to move certain distances (mainly diagonal ones) across a large shelving rack. Homework Equations The...

Homework Statement I am trying to design a workshop crane and have found a considerable success so far. It is a maximum 2 ton crane and i have found which I beam to use by the method mentioned below. Some of the specifications are boom length(span) = 3 m mast length(vertical portion) = 4...

Homework Statement "A motor having an efficiencyof 88% operates a crane having an efficiency of 42%. With what constant speed doess the crane lift a 410-kg crate of machine parts if the power supplied to the motor is 5.5kW" e'=42% e=88% m=410 kg dr=? de=? t=? g=9.8m/s square...

Homework Statement The figure above is a simple model of a crane. The base has a mass of 2000kg, and the boom has a mass of 200kg. What is the maximum mass of the ball if the crane is not to tip over? Note, in order for the crane to be stable, its center of mass cannot be outside the...

Homework Statement At the instant shown in the figure , the crane's boom has an angle = 33.0 and rotates around the vertical axis with angular velocity = 8.00×10^−2 radians/s that increases at the rate = 7.00×10^−2 radians/s^2. At the same instant, the crane's boom is rotating upward...

Good Day, I have the task of rerofitting an AC inverter that controls the long travel on a crane at a shipping terminal which has built in software to prevent swaying of the load automatically. It is operator driven and this control is to compensate for operator short falls. The only feedback...