Construction Machine Blog

The concrete mixer is a very important piece of equipment for the modern construction field. As we all know, the main material of making a mixer is steel. Being made by steel is the reason why concrete mixers tend to be heavy and stubborn. From the right birth of concrete mixers, inventors have been thinking about how to help mixers lose weight. However, little progress has been made until recently the invention of the plastic drum. As we can see, drum is an important part consisting of a concrete; it takes a great proportion of the whole weight of the mixer. With the lighter plastic drum, the total weight of the concrete mixer is greatly decreased.

 Plastic drum mixers

The drum includes a bottom supported by a conventional rigid metal pan secured to the external surface thereof to rigidify the plastic drum and extend the life expectancy of the plastic drum by enabling the concrete mixer to be used to complete a mixing job at a job site even though movement of the concrete mix within the drum during repetitive mixing cycles may ultimately wear a hole through the bottom of the plastic drum. Paddle assemblies are positioned interiorly of the drum and oriented to maintain minimum splashing during the mixing operation. A rigid ring gear is attached peripherally of the drum in spaced relation to the metal supporting pan with the drum, ring gear and metal bottom pan being uniquely related to facilitate assembly and disassembly of the components to facilitate easy replacement of the components.

Steel drum mixers 

Concrete mixers of the type utilizing a generally vertically or angularly disposed mixing drum driven about a longitudinal axis with a paddle assembly mounted interiorly of the drum are well known. The drum includes a rigid peripheral ring gear mounted peripherally of the drum above the closed bottom end and below an open top end for rotating the drum about a generally longitudinal axis. The drum is supported from a frame by a yoke pivotally supported from the frame and a cradle assembly to enable pivotal movement of the drum from a generally vertical position to a tilted position with the open end of the drum being disposed below the pivotal axis of the drum to dump mixed concrete from the drum. A manually operated wheel or handle structure is associated with the yoke and frame to manually pivot the drum between a mixing position and a dumping position.

 Mixer with plastic drum-United States Patent 5492401

Concrete mixers as described above in which the drum is constructed of metal have been used for many years. In view of developments in plastic materials, recent efforts have been made to utilize a mixing drum constructed of plastic material in lieu of a metal mixing drum. High density crosslinkable polyethylene or suitable equivalent plastic material has been used rather than heavy steel and certain advantages are derived from the use of the plastic material, such as, reduction in weight, easier and more effective cleaning of the drum and substantial reduction in labor intensive removal of hardened concrete which, when bonded to the interior of a steel mixing drum, requires extensive effort and time to remove.

Although currently only the drum can be made by plastic, we have good reason and confidence to believe that we can make the whole machine of a concrete mixer by plastic. At that time, the time, the mixer will become lighter and smaller and smarter.

In the modern society, we can hardly imagine a world, or even a city without brikcks. Without bricks, no modern construction is possible, including long bridges above the rivers and skyscrapers high in the air. Human beings have used bricks for a long time. As I have mentioned in my previous posts, Chinese people used bricks to build the Great Wall as early as in the Ming Dynasty(around 13^th century). At that time, however, bricks were made by hands and its productivity was very low. To meet the increasing need for bricks, people in industrial period invented the brick making machine. However, modern people are more and more dissatisfied with the speed of the traditional brick making machine. Fortunately, now we finally witness the appearance of a new type of brick making machine: the high speed automatic brick making machine.

As the name of the invention shows, the new ones are not only high-speed but also automatic. An automatic machine for pressing bricks at high speeds is provided with a pressure wheel and pressing tongues attached to the circumference of the wheel through an axle which permits the tongues to rotate or swing about the axle. Clay material is fed to an endless belt comprising a plurality of moulds, pressed by the pressure wheel, and then conveyed to a release station. The railing for the endless belt has an expanded portion so that the end walls of the moulds are released outwardly as they pass this portion, allowing the pressed brick to drop to another belt to be sent to an oven.

A high speed automatic brick making machine comprising:

(a) a pressure wheel having at its circumference brick pressing tongues said tongues being free to rotate and each being attached to said wheel by means of an axle passing through the tongue, the ends of the axle being fixed to the circumference of the pressure wheel;

(b) a plurality of moulds disposed on an endless belt, said moulds having a pair of side-walls and a pair of expandable end walls, said moulds corresponding to said press tongues the press tongues reducing the height of the material in the moulds by about one half, the railing for the endless belt having an expanded portion whereat the end walls expand to release the compressed brick contained within the mould after compression;

(c) a hopper for feeding clay to the moulds; and

(d) driving means for said pressure wheel and endless belt.a

The crane is a necessary piece of equipment to the modern construction field. A crane tends to cost a large sum of money and its maintenance is also very expensive. Although there are many professional companies have been set up to offer crane maintenance service, their charge is a little bit high. Thus if the crane owner is able to repair the crane by himself, he can surely save a lot of money. As a matter of fact, very body can offer cranes a good maintenance as long as he is familiar with the machine and has some basic knowledge of maintenance.

Crane Maintenance

When a crane gets broken down, the first step we should do, of course, is not to fix it instantly, but to check each part of the equipment to see where the problem lies. It is something a doctor should have a diagnosis on his patient to find out the cause of the disease before he can take any actions. As for the diagnosis of the crane, the following are some details we should pay special attention when inspecting a crane.  

The typical structure of a crane Read more…

Not long ago, I have written an article on how to buy a used backhoe. In that post, what I was trying to do was to explore the functions of the backhoes. However, this time in this post, I want to give you readers some advice on the same topic how to buy a used backhoe from another perspective, the physical structure and features of the used backhoe.

The used backhoes for sale

The backhoe equipment consists of three parts. The main one is the tractor. The loader is the second part of the backhoe equipment. The loader is a big rectangular shaped device which scoops the material.

The third part is the buckets at the rear of the tractor. Typically, if the bucket is being used, the flat front end of the loader is set down on the ground to stabilize the vehicle. Optional backhoe equipment includes street pads and rear stabilizers for increased performance and versatility (for some models only).

The main parts of a backhoe

When buying used backhoe equipment, you must have it properly inspected to ensure that it is free of any mechanical, hydraulic, or electrical problems. Of course, used backhoe equipment is much cheaper than brand new, but you must take into account the maintenance costs.

Finding the right used backhoe service solutions will increase your productivity and profitability while lengthening the life of your used backhoe. The people working at the service are responsible for supplying you with all the necessary new and used backhoe parts to keep your used backhoe in top shape. The best idea is to sign a contract with a service that has several different part departments within your state. In that way, wherever you are with your used backhoe, the service will be close by with the parts you need.

The maintenance of  backhoes might cost a lot of money

When buying used backhoe equipment, don’t forget that there will surely be some maintenance costs associated with its use, so it’s not just about choosing the model, but also the dealer and service. Such heavy duty construction equipment, especially second-hand, will wear and break at some point, so your relationship with the dealer is very important for preventative maintenance and repairs. Find about your dealer’s service policy, check how they handle breakdowns and who should transport it, can they provide you with a backhoe until yours is fixed? This is very important, because such serious construction projects have to go as planned in the schedule, so consider what can happen if you loose your backhoe for a week due to repairs. Also check their parts inventory, because you don’t want to wait for parts.

In a word, before your buying a used backhoe, you must have some comparison between the expense you would spend on the future repairing and the extra money you have to offer if buying a new backhoe. Nobody wants to end up spending more money in the long run (like 10 years) compared to buying a brand new backhoe loader. Of course, prices drop significantly once the machine has a few thousand hours of use. The number of hours used is a main criteria when estimating the price. Generally speaking, the more time a backhoe has been put into use, the less its price should be.

A skid loader, also called a skid steer loader sometimes, is an engine driven machine with lift arms used to attach a wide variety of labor-saving tools or attachments. Though sometimes they are equipped with tracks, skid-steer loaders are typically four-wheel drive vehicles with the left-side drive wheels independent of the right-side drive wheels. Developed in the late 1950s, skid-steer loaders are sometimes referred to as bobcats.

Skid Loaders

There are two physical characteristics that make skid loaders unique among loading equipment. First, the vehicle has the ability to turn around in a space that is no larger than the length of the loader. The combination of being a compact track loader and being able to make a full turn in such a small amount of space makes the skid loader ideal for use in tight spaces. Second, the skid loader is equipped with lift arms that are located on the sides of the vehicle, rather than incorporating a lifting mechanism on the front of the unit. The pivot points of the loading mechanism are located to the sides and just behind the driver’s seat, which goes a long way to distribute the weight of the load evenly. While many early models of the skid loader featured an open cab for the driver, today’s compact track loaders usually include an enclosed cab, adding an element of safety.

A Skid Steer loader can sometimes be used in place of a large excavator by digging a hole from the inside. The skid loader first digs a ramp leading to the edge of the desired excavation. It then uses the ramp to carry material out of the hole. The skid loader reshapes the ramp making it steeper and longer as the excavation deepens. This method is particularly useful for digging under a structure where overhead clearance does not allow for the boom of a large excavator, such as digging a basement under an existing house.

Skid Loaders can work as excavators

Generally, the standard equipment on a skid loader is a bucket that can be used for scooping surface elements, as well as for excavation. However, it is possible to replace the bucket with a number of different attachments. Among the attachments that can be worked with the design of the skid loader are sweepers, augers, mowers, snow blowers, and trenchers. It is even possible to include a woodchopper or a cement mixer as an attachment.

Skid Loaders’ Bucket

The versatility of the skid loader makes the device makes it valuable in a number of settings. Farmers can benefit from use of the skid loader as an easy means of cleaning up around the property as well as moving lumber and other heavy objects from one location to another. Around a construction site, the skid loader is ideal for loading and unloading materials, transporting sand or bricks from one section of the site to another, and removing debris from the site.

In a word, the skid loader is one of the smartest pieces among the construction machinery family. As a new born member of the family, it will play a more and more important role in the construction field.

The backhoe is the most delicate piece of modern construction equipment on the market today. Its versatility and flexibility have brought into it a broad range of application from digging to excavating. However, a new backhoe is always very expensive. As a result, many people, especially those foremen, would like buy a used backhoe to save money. There are also some people to buy used backhoe for sale. With all these causes, the business of used backhoe is very flourishing. For each individual, no matter he buys a used backhoe for construction or for sale, there are some common principles that he should bear in mind.

Backhoes are working

When looking to buy used backhoes for sale, one of the first things to consider after you’re done a test drive, is the proper inspection of the used backhoe. This insures, as much as possible, that it is free of any mechanical, hydraulic or electrical problems.

For instance, new paint jobs can look good, but are sometimes used to cover up more serious problems. Look for signs of fluid leaks and concealed rust spots to find potential problems. Check underneath the vehicle for evidence of leaks. Inspect hoses and valves before and after the test drive, so you can easily spot fresh leaks.

Although backhoes are much cheaper than brand new ones, you must take into consideration the maintenance costs. Make sure that you are given any necessary new and used parts that belong to the backhoe in order to keep it in top shape. If the used backhoe for sale is purchased from an equipment dealer, sign a service contract with the dealer, whereby they have several parts departments within your state. In this way, wherever you find yourself with your used backhoe, the service will be nearby with the parts needed.

A full picture of the backhoe

Before buying a used backhoe for sale from a private individual, ask a dealer or manufacturer for a checklist of what you should know and/or be looking for, to insure good decision making. Making calculations when purchasing a good used backhoe, is paramount in your decision making. The number of hours used should be one of the main criteria when estimating the price, because you do not want to end up spending more money in the long run. In other words, the more the hours it has been in use the less the price it is.

An used backhoe for sale

In order to make this determination, get new backhoe pricing info versus used backhoe pricing info on the brand you have chosen, from a manufacturer, or go online and surf the web to find this information, and use it as a guide towards a good buying decision. OSHA rules require specific training and safety procedures for operating all heavy machinery and that would include used backhoes. So, get that training from a dealer or a recommended third-party source. With these few tips in mind and your good judgment, you should be able to find a used backhoe for sale that can still get the job done.

In conclusion, no matter what you’re going to buy, no matter it is new or used, the quality/price issue is always the first thing you think be concerned about. Only buy these things that qualify your task.

Concrete mixer is a very important construction equipment. Every construction, from setting up a tall building to establishing a small house, at least one mixer is needed. What’s more, as its being used so frequently, mixers get broken down easily, which makes the purchase of mixers necessary and important. However, with so many brands and choices on the market, to buy a right mixer is not an easy job at all. The following is something you should always bear in mind before buying a mixer.

Various Concrete Mixers

The concrete mixers are largely used on civil construction, mostly to build houses, dams, bridges and infinity of others tasks. It has also other uses like mixing rations or manure, but on these cases it calls only mixer.

 They normally measure the capacity of the mixer in liters that corresponds to the dum capacity. The best you can get is a concrete mixer that provides you homogeneity and does it quickly. The homogeneity is determined by the type of mixer, the order of introduction into the mixer, and duration and power of mixing.

 Efficiency is the best way to achieve success on your daily work, don’t buy one just because is the best price you can find in market, always give preference to relation quality/price, you can save 10 bucks today and lose 1000dollars tomorrow, you have to measure the pros and cons of acquiring it, facing the idea that only a quality mixer will perform such task well, they are also more resistant to daily work, they need less repairing, and they are normally easy to repair, look also carefully the energy necessary to produce concrete, this could reveal a high bill at the end of the month.

 For homeowners, for tasks like repairing, a concrete mixer between 140 liters and 300 liters should be the adequate, otherwise for industrial projects that need a large amount of concrete consider buying a concrete mixer between 350 liters and 1000 liters, but always depends on the project.

 If you are going to choose the best concrete mixer for a specific application, you must consider these factors, location of the construction site, the amount of concrete needed, the construction schedule, and the amount of concrete that you will need.

Although specific advance on how to buy a mixer is not given, I suppose every dear readers would have gotten some ideas to set up their own standards. And I believe that bearing the above in mind, everyone can be a successor or winner in the purchasing a mixers. Good luck to all my dear readers.

Wherever you are in a city, there are lots of things that always keep visible for you. Among them, tower crane is the most common one. Whenever we raise our eyes on the street, we would see many tower cranes swinging in the sky above the city. They are so high and seemingly so dangerous that you cannot ignore them. They are usually used in the construction of tall buildings. What’s more, their height can grow as the building grows taller. As such a heavy equipment, how are the tower cranes able to grow with the growth of the building? For once a while, this question had bothered me. And if you dear readers were confused with the same question, then reading the post will dispel all your suspicions.

Tower cranes arrive at the construction site on 10 to 12 tractor-trailer rigs. The crew uses a mobile crane to assemble the jib and the machinery section, and places these horizontal members on a 40-foot (12-m) mast that consists of two mast sections. The mobile crane then adds the counterweights.

The mast rises from this firm foundation. The mast is a large, triangulated lattice structure, typically 10 feet (3.2 meters) square. The triangulated structure gives the mast the strength to remain upright.

To rise to its maximum height, the crane grows itself one mast section at a time! The crew uses a top climber or climbing frame that fits between the slewing unit and the top of the mast. Here’s the process:

1. The crew hangs a weight on the jib to balance the counterweight.
2. The crew detaches the slewing unit from the top of the mast. Large hydraulic arms in the top climber push the slewing unit up 20 feet (6 m).
3. The crane operator uses the crane to lift another 20-foot mast section into the gap opened by the climbing frame. Once bolted in place, the crane is 20 feet taller!
   

 You dear readers may be also wandering how the tower crane comes down when a building is finished. As long as you have understood the above steps, the question is naturally solved, because the process is reversed — the crane disassembles its own mast and then smaller cranes disassemble the rest. As we can see, the whole process are actually not confusing at all, although a little bit complicated indeed.

The tower crane is a modern construction equipment, which is frequently used in the construction of tall buildings or long bridges. Although we happen to see a tower crane from one time to another, most of us have never looked them closely. What is its structure? Which parts it include? And what the respective function of each part? This post is going to shed some light on these questions.

Tower Crane And Its Parts

Although there are various tower cranes of different types and models on the market, the basic physical structure is the same for all of them. Tower cranes, regardless of their types and models, are assembled by such mechanic parts as jib, rigger and so on. The following are details about these parts, including their pictures. I hope this can help you dear readers better understand what a tower crane really is.

Here are some basic parts of tower cranes

The base is bolted to a large concrete pad that supports the crane.

The base connects to the mast (or tower), which gives the tower crane its height.

Attached to the top of the mast is the slewing unit — the gear and motor — that allows the crane to rotate

On top of the slewing unit are three parts:

The long horizontal jib (or working arm), which is the portion of the crane that carries the load. A trolley runs along the jib to move the load in and out from the crane’s center:

 The shorter horizontal machinery arm, which contains the crane’s motors and electronics as well as the large concrete counter weights:

 The operator’s cab:

 The machinery arm contains the motor that lifts the load, along with the control electronics that drive it and the cable drum, as shown here:

 The motors that drive the slewing unit are located above the unit’s large gear:

Bulldozers are important equipment in the construction industry. They are crawlers which are equipped with a blade. Since their first appearance, bulldozers have covered a history of over 100 years. During this period, interesting anecdotes have happened from one time to another, many of which keep unknown to most modern readers. The following are some I picked from lot stuffs.

Bulldozers are developing 

Who Is The Inventor of Bulldozer?

There is still -no unanimous answer to the question who invented the first bulldozer. Many historians tend to attribute this reputation of having invented the bulldozer to an American named Benjamin Holt, and originally calling it a “caterpillar” or a crawler tractor. However, this would be misleading.

Benjamin Holt and His Bulldozer

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