Construction Machine Blog

Concrete pump is tool to transport concrete from one place to another. Somebody hold the view that buying a concrete pump is a waste of time because the task of transportation can also be accompanied by other construction tools. Yes, it is indeed true that concrete pump is not something essential and indispensable for a construction project, and its role can be replaced by many other tools such as trucks. However, concrete is still very important to construction.

 Concrete Pumps

Why concrete pump? The answer lies in its numerous advantages.

To begin with, Concrete pumps are the best option for placing concrete at the construction site at a faster rate. Some people think a concrete pumps means an unnecessary expense. But what they ignore is that using a concrete pump actually improves the efficiency and speed, saving workers a lot of time and energy.

Besides, Concrete can be placed easily and at a faster rate at inaccessible sites. A concrete pump places concrete faster with less labor than any other method. You can save money and free up valuable personnel for other duties. Direct placement without re-handling improves concrete quality and reduces labor. A concrete pump causes less congestion than most other methods.

In addition, using specialized concrete pumps reduces the labor as less handling is required since concrete can be placed directly at the desired location. This saves the construction forehead a large sum of money for the expense of the building workers. In other words, using concrete pumps can not only save the power and energy of the workers but the over-head cost of the boss.

Last but not least, concrete placing is not affected by weather conditions. It can work under any tough weathers. Thus there is no worry about the delaying of the construction due to the problems of the concrete pump. Especially in winter, when icy and stormy weather frequently happens, concrete pump can guarantee the speed of the whole construction project. What’s more, concrete pump is Reliable and it can assure high quality work. The maintenance fee of the concrete pump is very low. After buying it, you would benefit from the concrete pump for a long time.

As we all know, without concrete, no modern building can be set up. Nearly every construction project needs concrete as well as concrete mixer. However, there is one problem with using concrete. That is how the building workers ensure concrete spread smoothly and flatly. This tough task is accomplished by the concrete vibrator, a very important equipment which usually ignored by many of us.

A concrete vibrator is a construction tool used on concrete pouring sites. A variety of manufacturers build concrete vibrators and an assortment of attachments designed for multiple applications. A concrete vibrator is used to ensure that a concrete pour is even and free of air bubbles so that the concrete will remain strong and have a smooth finish.

Concrete Vibrators are working

Although it also works without concrete vibrators in those small jobs, a concrete vibrator is essential on large load bearing projects.

Basics of Concrete Vibrators

Concrete vibrator designs range in size from small battery-powered wands to much larger plug-in versions that be used on very deep pours. In all cases, a concrete vibrator that can reach the bottom of the pouring forms should be used, ensuring even treatment of the entire concrete pour. Attachments for the concrete vibrator are selected on the basis of the depth of the pour and the type of concrete being used.

A concrete vibrator uses an off-centered weight, which is spun as much as 10,000 times a minute, causing large air pockets in the concrete to disperse as the concrete is shaken. Especially in pours of low slump concrete, which uses minimal water, the use of a concrete vibrator is essential to ensure that the concrete does not bubble or form holes. In cases where consumers will be looking at the finished concrete, as is common in some schools of design that employ concrete counters and floors, use of a concrete vibrator will present an even and attractive surface, rather than one that may be slightly ragged.

 Parts and types of Vibrators

Correct Operation of a Vibrator

Proper use of a concrete vibrator requires some training. The head of the concrete vibrator should always be slowly lowered into the pour and pulled out gradually to avoid the formation of an air pocket. A concrete vibrator should never be dragged through a pour, because it will leave a groove in the concrete behind it. The amount of time required varies depending on the mix, but it does not usually take more than 30 seconds to settle the concrete sufficiently and move on to the next section of concrete.

If a concrete vibrator is used incorrectly on a concrete mix with a wide range of material sizes, it may cause the larger rock pieces to settle to the bottom, making the concrete weaker. In addition, a concrete vibrator can push rock and gravel away from the area being shaken, causing weaker concrete paste to fill the area, which may result in instability. The goal in using a concrete vibrator is to build a strong matrix of material that will withstand years of use. If the concrete vibrator is used correctly, the operator will see large bubbles floating to the surface of the concrete pour, and a layer of mortar will appear on the surface to indicate that the concrete is evenly mixed and unlikely to have air pockets and honeycombing.

check the working of vibrators

Of course, to become a qualified operator to achieve such an effect, a long time of practice shall be taken.

The crane is a very versatile construction equipment. As I have mention before in my previous posts, there are many types and shapes of cranes in the market such as truck crane and tower crane. Different types of cranes are used on the basis of the amount of weight to be lifted and the area available for movement at the construction site. Today in this article, I want to focus my attention on jib crane, another important member of the crane family. You dear readers would also learn about the various types of Jib cranes in the article.

 Jib Cranes

The design of a Jib Crane

As a common type of cranes, the jib crane consists of a pillar fixed to the wall or mounted on the floor. The pillar supports a horizontal jib, or boom which has a movable hoist. The hoist is used to lift or lower a load with the help of a drum, or lift-wheel, which has a chain or rope wrapped around it. The drum is driven electrically or pneumatically, and can be operated manually. The lifting medium is usually a chain, although it may also be a fiber rope or wire cable. The load is lifted with the help of a lifting hook attached to the lifting medium.

 The design of jib crane

 Types of Jib Crane

As a particular type of cranes, jib cranes can also be divided into several types. The floor mounted type, wall mounted type (fixed) and wall mounted type (traveling) are the three main types. Let’s see them in details one by one.

 Floor Mounted Type

This is the most commonly used Jib crane. Floor mounted jib crane is a self-supporting jib crane having a vertical mast mounted on a concrete foundation. These types of cranes are generally used to share the load of main cranes. The construction of the crane is as described above. All these cranes can rotate 360 degrees and are manually operated.

  Wall mounted type (fixed)

This type of crane is mounted horizontally on the wall and instead of a vertical shaft has a RCC column bracket mounting. The hoist mechanism is similar to the floor mounted type, but without a vertical boom. The RCC column bracket allows a maximum rotation of 200 degrees but covers the area near the bracket mounting without obstruction at floor level.

 Wall mounted type (travelling)

The construction of this type is similar to that of fixed type with the only difference that the crane is able to cover the lengthwise area near the building columns without obstruction at floor level. The crane’s columns are specially designed and the crane instead of rotating, moves along a runway track suspended along building columns.

Through this article, I hope all of you dear readers have a better understanding about cranes and jib cranes.

Introduction

A concrete pump is an important role in the construction machinery family. It is a tool for transferring liquid concrete by pumping.

Concrete Pumps are working at the construction site

There are mainly three classifications of concrete pumps:

• Boom or truck mounted pump
• Trailer, line, or stationary pump
• Specialized usage pump

Let’s briefly look at these three types of pumps

 Type 1: Truck mounted pump

As its name shows, the truck mounted pump is attached to a truck. It is known as a truck-mounted boom pump because it uses a remote-controlled articulating robotic arm (called a boom) to place concrete with pinpoint accuracy. Boom pumps are used on most of the larger construction projects as they are capable of pumping at very high volumes and because of the labor saving nature of the robotic arm.

 Truck mounted pump

Type 2: Trailer Pump

The second main type of concrete pump is mounted on a trailer, and it is commonly referred to as a trailer pump or line pump. This pump requires steel or rubber concrete placing hoses to be manually attached to the outlet of the machine. Those hoses are linked together and lead to wherever the concrete needs to be placed. Trailer pumps normally pump concrete at lower volumes than boom pumps and are used for smaller volume concrete placing applications such as swimming pools, sidewalks, and single family home concrete slabs.

 Trailer Pump

Type 3: Specialized usage pump

These pumps are specifically made for specialized job sites such as mines and tunnels. They are also skid mounted and rail mounted concrete pumps but are not commonly used due to their high costs and extra specialized mechanism

Specialized usage pump

Although the backhoe is a very productive and helpful construction equipment, it is must be used safely and efficiently. There are many construction accidents related to backhoes or mistakes made by their operators. To be a qualified backhoe operator, he should not only have a good master of the operating skills, but also bear a strong sense of safety in mind, knowing how to prevent himself as well as others from being hurt. And to a judge a operator whether he is good or not, we should focus more on his safety sense than on his operating skills because safety comes first.

Of course, to avoid backhoe accident, the best way an operator can do is to be fully aware of yourself, the jobsite, and the features of the equipment you are working with.

Although the models of backhoes vary, there are safety features with all of them that include steps and grab handles for getting on and off of the machine. Backhoes also feature frame lock levers and attaching levers to keep the backhoe securely fastened to the loader frame during operation as well as transporting.

Some Parts of Bakhoe

In addition to these standard safety features, there are some backhoes that provide a safety chain. The safety chain will prevent the backhoe mounting frame from rotating backwards and unexpectedly trapping the operator, which can result in serious injury or death. Therefore, it is always important to know and check all of the mounting and attachment points and the safety chain before you operate the backhoe.

Read more…

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.