A saw is a tool that uses a hard blade or wire with an abrasive edge to cut through softer materials. The cutting edge of a saw is either a serrated blade or an abrasive. A saw may be worked by hand, or powered by steam, water, electricity or other power.
Types of Saw:
1. Hand Saw:
Hand saw uses the blades thickness to remain stiff. The pull stroke also reduces the amount of stiffness required. Some examples are: crosscut saw, rip saw, veneer saw. The second category of hand saws utilizes a thinner blade by reinforcing it with a steel or brass back. Back saws are differentiated by the length of the blade. Some examples are: miter saw, tenon saw.
Concrete Sawing:
Concrete Saw is a type of hand saw which is powered by an internal combustion engine and used with a Diamond Blade to cut concrete or asphalt pavement. This is also referred as flat sawing Concrete slab saws can be powered by gasoline, diesel, electric, hydraulic and even pneumatic engines. The slab saw diamond blades can range from 12 60 inches in diameter and can cut up to 27 inches in depth. A 120 horsepower, water-cooled, gas powered slab saw can cut up to 27 inches deep. When no exhaust or fumes are allowed, such as in food preparation areas, hospitals, and in enclosed shopping malls, an electric or hydraulic concrete cutting saw is used.
Concrete Slab sawing is used to cut steel, reinforced concrete, metal, stone and pre-cast concrete surfaces. Flat sawing allows to cut roadways, bridges, concrete slabs and side-walks .Slab Sawing service allows very precise cutting jobs.
Road cutting is used for cutting the monolithic slabs, bridge decks, trenches in floors and in foundation walls.
Floor sawing technique is primarily used for making floor opening for HVAC, electrical and plumbing trenches in construction projects. 2. Mechanically Powered Saws:
Mechanically powered saws are different from hand saws in that the blade moves while the wood remains stationary. Few examples of saw blade are: circular blade saw, reciprocating saws. Electric miter saw, (also called chop saw, cut-off saw or power miter box) is used for making accurate cross cuts and miter cuts. The basic model has its circular blade fixed at a 90 angle to the vertical, a compound miter saw’s blade can be adjusted to other angles. A sliding compound miter saw has a blade which can be pulled through the work similar to the action of a radial arm saw, which gives a greater capacity for cutting wider work pieces.
Types of Blade:
Selection of right blade is the most important point of consideration while performing any job.The saw blades seems to be similar but are different on practical rounds and there is a particular blade for a particular job such as for plywood, lumber and laminates. The blade performance depends on the teeth and size of blade used. Selection of wrong blade can result in ragged edges of the material being cut.
If saw blade teeth are 24 or fewer, this is likely to be a rip blade. If the teeth are square across the top, or if the tips are bent sharply to the left and right, this is called “set.” This saw blade is for cutting lumber lengthwise, or “ripping lumber.” It is designed to cut lumber fast, but the cutting edge will be rough.
If saw blade teeth are between 60 and 80, it is a cross cutting blade. The combination of square top teeth, and teeth with a slight slant inwardly saw blade is used for making smooth cuts. It is designed to cut plywood in any direction and lumber ACROSS the grain.
If the size across one teeth is approximately 1/16 inch, or half as thick as all the other blades. This blade is for cutting veneers like plastic laminate, Formica, Plexiglas or other composite materials. This blade is not used for cutting wood.
Golden Tip
The more teeth the saw blade has , the slower and smoother the blade will cut.
The sharper the points of the saw blade are, the faster the blade will cut, but with a rougher edge.
In construction industry every project involves nearly some form of cutting concrete or core boring. Hand-held saws are used in the construction project to cut or shape paving slabs, stones or other concrete products.
Cutting concrete may seem to be simple but on practical ground there are several safety measures to keep in mind to have a safe and successful concrete cutting or boring project.
Safety and concern becomes an issue with concrete cutting because the concrete dust generated by the cutting action contains high respirable crystalline silica content. Breathing in this dust can lead to the development of respiratory ill health affecting your lung tissue resulting in serious breathing difficulties depending on the extent of exposure
Therefore, dust control becomes an important consideration when cutting concrete either with a saw or a drill or core boring bit.
The two most dust Control methods are:
1. Wet Cutting System:
In wet cutting the dust is collected in the cooling water and pneumatic devices that pulls the dust away in an air stream. Wet systems are preferably used on saws powered by combustion engines or compressed air. Wet dust suppression should not be used on saws that are electrically operated.
Wet cutting systems spray water onto the rotating cutting disk to reduce dust emissions. There are two sources by which water may be supplied.
(a) Portable Pressurised Tank System
This pressurized tank system consists of a polypropylene bottle containing approximately eight litres of water. The bottle is connected by narrow plastic tubing to two spray heads or jets normally attached to opposite sides of the guard. An on-off valve is fitted to control the water supply. An in-line filter is often fitted to prevent the heads becoming blocked. The spray heads/jets can be made from polypropylene but brass is considered a more resilient material. Water flow is produced by pressurizing the tank by hand.
(b) Mains Water System
This system is essentially the same as the tank, except the water source is from mains supply through a hose to the two water jets. Studies have shown that a minimum flow rate of about 0.5 litres per minute is required to optimise dust suppression. Low flow rates will reduce performance. Very much higher flow rates do not improve dust suppression, they only increase the need to refill the portable tank more often.
Difference between Portable and Main Water System
The portable tank needs to be regularly pressurised to maintain the flow rate.
The mains water system does not have this limitation but portability is restricted by the need to cut near a mains supply. The portable tank is more flexible as it can be easily transported around the site but it still requires a water source for refill.
For cutting a paving slab with adiamond tip blade normally requires a single pressurization stroke with portable system whereas tank sytem require re-pressurising during the cut if adequate control is to be maintained.
Precautions:
Diamond cutting blade or other abrasive disk cutting device such as concrete saw, uses water to lubricate and cool the cutting tools. The spillage of cooling water on to the surface during cutting should be managed by providing a drainage or a vacuum system like a wet vacuum which can be used to control the spillage of cooling water.
When using electric powered tools, adequate grounding, insulation and appropriate ground fault protection must be provided. If proper safety measures are not taken by the operator while operating electric toll and standing in a puddle of water can be fatal .
Core drilling machine requires an additional precaution as most of the machines depend on suction to keep the base in place during the drilling operation. The friction of the base suctioned against the floor provides the resistance to rotation while drilling depending on wether the floor is slicker or rough. The rough floor may provide more friction and will not allow a strong vacuum seal against the floor. In either case the vacuum seal is not completely reliable and may fail during the drilling operation. The operator must be aware about this and should keep his body out of the possible rotation path of the machine base during core drilling operation.
A reliable and secure method to work with core drilling machine is to have a concrete anchor through the base in addition to the vacuum seal. Most machines have a provision for such an anchor and the small hole required for the anchor is easily repaired in the concrete floor.
What lies beneath the concrete should be an important consideration even for a straight line cut with a concrete saw or making a round hole with a core drill. Concrete imaging and scanning is the technique used for relocating the presence of rebar,pipes, conduits, steel wire mesh,sinkholes, plumbing holes or even electrical conduits often buried in or under the concrete.
Concrete cutting equipments require sharp tools, a good supply of cooling water and a skilled operator to handle these machines. Operating concrete cutting equipment can be simple and safe, but the operator must be familiar with the potential hazards and should be well skilled in his concrete cutting profession.
2. Local Exhaust Ventilation:
The method of local exhaust ventilation used on hand held concrete cutting saws uses the saws guard as a type of high velocity hood. The guard is connected to an industrial vacuum cleaner which provides sufficient exhaust ventilation tocapture the majority of dust emitted during the cuttingoperation. Guards with adjustable inner sleeves are preferable. These maximize enclosure and can be adjusted toaccommodate different depths of cut. This system does not produce the wet slurry associated with wet dust suppression.
Common Problems and Solutions with Control Systems:
(a)Wet Systems Chalk is used to mark the line of cut which can easily wash off by water supply generated in wet system. Wax crayons or a carbon brush (from oldelectric motors) are better options to be used instead of chalk.
Operators require waterproof PPE as both pressurized portable system and mains water system make use of water.
(b)Local Exhaust Ventilation
Abrasive wheels wear during cutting activities. A system with an adjustable inner sleeve does not automatically compensate for abrasive wheel wear. Diamond wheels wear less quickly and are recommended for this system.
A generator is required for both vacuum cleaner and saw. Small portable generators can be moved around the site on a wheel barrow.
Operators should be aware of correct posture as local exhaust uses 9 inch diameter wheels which require operators to bend a little lower during cutting operation.
Personal Protective Equipment
Concrete cutting operator should be provided with suitable RPE as concrete cutting products contain high silica.
Dust mask is required while emptying the vacuum cleaner.
Construction is a job of skilled manpower and dealing with concrete becomes a strong element of construction job scope from a minor patch of drilling to a major patch of pourback with efficency.
Most large concrete companies are able to provide labor services, from coring to concrete cutting, but with not highly skilled craftsmanship labor. The balance of skilled workmanship and personal customer service, has to be the prime objective of any project. Hiring a concrete contractor who specializes in drilling, coring, and cutting is the only way to ensure a top quality and cost-effective job.
For slab or masonry cut work requirement, any company could be called, but for job efficiency,cost control and top quality it is best to call a concrete contractor with specialized training in coring and cutting. For a new window or door to be installed, an area has to be created in a wall which requires slicing through several layers of thick cement. Finishing of basement bathroom along with the installation of pipes, requires drilling trenches into the foundation slab.This again needs a very conscious effort as the concrete contractors have the scanning facility to see deep beneath the concrete to avoid any damage or accident.
We can also do certain part of the work but lack of the tools or know-how to undertake such projects just leads to increase of job with messy conditions. Fully-equipped concrete contractor or concrete company will be able to perform any type of drilling and cutting job required for construction job completion.
The specialization of masonry and cement cutting is concrete coring. Any type of job that is a part of electrical wiring, plumbing, or heating and cooling infrastructures that pass through a slab or wall, coring or drilling is required for wiring. Hiring a skilled professional company allows job efficiency and cost effectiveness in addition allows any serious structural damage.
Concrete cutting is the technical process that is used by professional operators to saw, drill and removal debris in accordance to proper calculations and measurements as needed. Various factories in US such as diamond cutting are using the new advanced techniques of concrete cutting. Instead of the old styled concrete cutting that used dusty jack and hammer method, the new fashioned tools of concrete cutting are sophisticated and updated equipments that are less messy and dust free.
If you need to cut concrete sidings of any door or window, there are certain tools available that can be used to snap concrete cutting in easy and smooth manner. Shear, circular saw and utility knife are some of the modern tools that are used by professional operators to perform concrete side cutting. Circular saws are easy and quick to use but to avoid the dust and mess, it is better to opt for shears.
To cut concrete sidings, it is necessary to follow certain safety instructions to avoid unwanted mistakes that can ruin the whole effort. If you are adventurous, you can yourself try cutting concrete siding for small needs in your home such as a door or window side cutting. Steps for cutting concrete sidings are given below that you can follows with help of proper precautions and equipments. While cutting concrete sides, the operator needs to maintain 100% focus and attention. Being unmindful during these works can lead to hazardous results.
Steps of cutting of concrete sidings in US
Measurements should be accurately taken by the operator using a gauge tape to ensure no mistake. The areas that need cutting should be marked properly in pencil.
Line up the measurement marks properly by using the straight edge ruler. Use the utility knife or shear along the lines marked to make a perfect guideline that will help to cut the concrete siding easily and well.
As you remove the straight line ruler, cut along the guideline in full force for several times with help of the utility knife or shear which in turn will create a score line.
As the concrete siding cut is taken off it will show the score line hanging from the edge. The sliding of the score line has to be snapped and pushed down.
Finally with the help of metal rasp, smooth out the edges of the concrete to give it an even finish.
There are many concrete sides cutting US companies who can help you with these works of concrete cuttings. They have the latest equipments along with years of experience and professional workers offering the best to their customers.
Concrete cutting is the method that comprises of technical process with which portions of home, buildings and roads are drilled and sawed. If you need to demolish and renovate a portion of your home, professional concrete cutting companies of DC can help you with your need. With new advanced equipments and techniques of today, the messy and dirt filled concrete cutting method is no more to be seen. New advanced equipments and methods of concrete cutting have taken over that are easy and quick to work with. Factories such as diamond cutting, road repair etc use the various advanced methods of concrete cutting to have their work done properly and smoothly with ease.
Concrete cutting methods used in US District of Columbia can be broadly categorized under three types that are commonly used by professional operators. Comprising of core drilling, wall sawing, concrete removal and concrete flat sawing, concrete cutting is a task that needs full focus and attention. Becoming unmindful during concrete cutting works can lead to hazardous and fatal results.
Methods of Concrete Cutting:
Core Drilling: With the help of this concrete cutting method, you can drill perfect holes on any form of concrete platform such as floors, walls etc. Commonly used in factories, core drilling can be done from various angels such as vertical, horizontal and upside down according to your need.
Operated with help of electricity or hydraulic power, concrete core drilling machine bits are available in diameter ranging from half inch to 72 inch.
Concrete wall sawing: Concrete wall sawing is another method of concrete cutting that is used to make openings for doors and windows in solid wall structure. To use wall sawing method, the thickness of the wall should range from 16 inch to 36 inch accordingly.
Concrete wall sawing requires experienced and skilled workers and cannot be performed by layman. It is one of the most expensive forms of concrete cutting that can be done in quick time with help of modern equipments.
Concrete Flat Sawing: Used to cut slabs for floor, bridges and pavements, flat sawing is also known as slab sawing. With the help of this modern machine, you can cut up to 27 inches deep. Widely used for making openings in concrete basements to make foundations, highway patching, plumbing trenches and runway repairs; flat sawing comprises of a diamond blade with a walk-behind mounted machine that can be operated with help of only one operator.
In a construction job it is often required to demolish certain portion of a building or even bring down the entire structure. Structural demolition services also include bringing down only a wall of a structure that may cause hindrance in the constructional work.
For smaller tasks selective demolition services are used. This structural demolition service may involve opening a room up by simply bringing down a wall. Dismantling jobs are also part of structural demolition services offered by professionals. For these kinds of jobs a demolition company can be hired. Structural demolition services also include removal of floor finishes, fixture removal etc.
Structural demolition for a large scale project can include demolition of the entire building. The steel structures would be brought down and dismantled. Structural demolition services are also required at sites that get damaged from fire or water. Professional demolition companies help in tearing down the damaged areas and often also offer debris removal services.
Structural demolition involves a process of series of explosions that cause a building or certain parts of it to collapse. A number of mechanical methods are applied to demolish constructions. Small houses are brought down or demolished with help of cranes. For demolishing comparatively large structures often wrecking balls and cranes are used.
Any structural demolition or removal of an existing structure can cause a safety problem. Demolition works often involves different hazards at the job site. Insulating materials, copper wires, asbestos, glass etc can cause potential hazards and thus extra precautionary measures are taken while demolishing and removing the collapsed structures.
After a structural demolition, the cleaning of the accumulated debris takes up a long time. The debris needs to be loaded and removed from the job site. Since health and environmental concern are associated with demolition work, it is undertaken as a carefully controlled process by the demolition companies. A thorough inspection of the site and locality is carried out by professionals before undertaking a demolition job. Safe work practices are also followed at the structural demolition sites for the security of the workers.
Diamond wire sawing is one of the essential processes of concrete cutting. Diamond wire sawing services are generally used at work sites of dams, docks, waste water plants and pier modifications. Skilled and experienced workers are assigned in wire sawing services.
