Plumbing works 01-basic and power tools

The delivery of liquids from one place to another is most easily done through pipe lines. In cities or towns the water is supplied and the waste water is disposed through networks of pipes. In many industries various types of chemicals and liquids are conveyed through pipes. Thus pipe work plays an important role in the development process.

This makes the cutting and joining pipes through the use of appropriate special fittings a very important profession. A person engaged in this profession is called a plumber and the plumber requires a special set of tools to do his work properly.

The major tools used in plumbing work are as follows:

Hacksaw Used for cutting pipes. It consists of a frame, handle, prongs, tightening screws and nut. The blade is fixed in position and tightened by means of the tightening screw. Hacksaw blades should be selected with due consideration to the material to be cut. The No. of teeth per cm, type of steel in the blade are the considerations to be given.
Hammers Hammers are required in plumbing for use with tools like chisels, for nailing, riveting and for driving objects into position. Different types of hammers are used for different types of work. Claw hammers – for driving and removing nails. Ball Pein hammers – for driving objects and for riveting. Cross Pein hammers – For sheet metal work.
Tape measure Consists of a graduated thin steel tape coiled and spring loaded in a box. A lever operated button automatically retracts the extended tape after measuring. The tape is graduated in cm and inches. Mostly used tool for measuring in engineering work.
Spirit Level Used to check true alignment to level (horizontal) and plumb (vertical). Spirit levels come in various sizes ranging from 150mm to 1200mm. Aavailable in wood or metal, the metal ones are easier to keep clean as they are easy to wash to remove mortar.
Pipe Reamers. For steel pipe. Pipe Reamers are used to de-burr steel pipe before threading. The reamer cone is made from tool steel and hardened for maximum life. Unique cutting edge makes this spiral pipe reamer self-feeding and easy to start and operate. For PVC pipe - Designed to chamfer pipe edges before joining, clean out the old or broken pipe and leftover solvent cement from a fitting so the fitting can be reused. Plastic Pipe Fitting Reamers are available in 4 sizes and fit into standard ½” drills.
Spanners A spanner or wrench is a tool used to provide grip and mechanical advantage in applying torque to turn objects—usually rotary fasteners, such as nuts and bolts.
Portable heating equipment When working with plastic pipes, portable heating equipment are needed to heat the pipes for bending and jointing. A blow lamp or a blowtorch is a tool for applying heat for various applications. Earlier the fuel in the blow lamp was pressurized by a syringe or a pump. Present-day the pressurized gas containers have replaced the built-in and often dangerous pump. Present day the blowtorch is referred to in industry and trade as per the fuel consumed by the tool: ·         Gas: Propane , butane or LPG ·         Liquid fuel – kerosene, gasoline, diesel or biodiesel
Pipe benders Steel, aluminium, copper or most metal pipes can be bent using the manual pipe bender. It allows users to create sections of piping at the exact angle needed for a particular application. The pipe is bent by the force exerted by the user onto the small handle of the device. Pipe bender springs Pipes are also bent by the use of springs. Springs can be either external or internal, i.e. the spring can be inserted into the pipe or the pipe can be inserted into the spring. The presence of the spring prevents wrinkles when bending.

PORTABLE POWER TOOLS.

Power tools are those powered by:

1.      An electric motor

2.      Internal combustion engine

3.      Steam engine

4.      Compressed air or

5.      Natural power sources like wind or moving water.

While power tools can be either stationery or portable, the scope of this lesson is limited to portable power tools only. Power tools are used for driving, drilling, cutting, shaping, sanding, grinding, polishing, painting and heating. Common portable power tools include the drill, hand saws, sanders, grinders and planers etc.

Power drill Just like the hand drill a power drill too has a chuck to fix the cutting tool or the drill bit, but rotating of the drill is powered. The on/off switch is located on the hand grip enabling emergency stoppages. To drill a hole the cutting tip of the drill bit fixed to the drill chuck is pressed against the target material and rotated by power.  Power drills can be used not only to drill holes, but also to drive or remove screws, countersinking, grinding, brushing and buffing etc. For drilling into concrete or masonry some drills have a percussion effect in addition to rotation. These are called hammer drills. For electrical safety it is advisable to use portable power tools rated at low voltages e.g. 110V. Since the supply voltage is 230V a step down transformer has to be connected to the power tool. A better solution to achieve electrical safety is to use battery operated drills. These are usually rechargeable and extremely safe. Electric drills should be well maintained by: 1.      Cleaning after use 2.      Checking power cable for damages and prompt replacing 3.      Checking electrical contacts regularly 4.      Not allowing the tool to come into contact with water or liquids 5.      Using on regular steady power supply 6.      Proper storage after retracting or rewinding the power cable	Battery operated rechargeable drill
Twist drill bits Twist drill bits get their name from the twisted pattern of grooves on the bit. Commonly used for drilling wood, plastic or metal. Twist drill bits typically range in size from 1/16 of an inch to 1 inch in diameter (or even larger in commercial applications). Twist drill bits are used at high speed for woodworking, but are turned much more slowly when drilling in metal to keep them from heating excessively. 1.      Bit Shank - The plain stem of the bit with no grooves is the shank which locks into the drill chuck. Point - The point of a twist drill bit is ground to form two chisel-like cutting edges extending out from the point at the center of the tip. For wood cutting bits, the point is usually at a steeper angle than on metal cutting bits. This allows the bit to cut more aggressively through the wood. Flutes - Deeply cut grooves that spiral upwards from the tip are flutes. The function of the flutes is to take the cut material out of the bore hole. Without the flutes, the drill bit will get stuck since it cannot eject the cut material.
Masonry drill Bits Masonry drill bits are a variation of the twist drill bit. The shank is made out of soft steel and the cutting tip has an insert of tungsten carbide brazed into it. Tungsten carbide is an extremely hard substance which can cut through concrete etc. Hammer drills are mostly used for masonry drilling and the drill bit is both rotated and hammered into the concrete or masonry. The hammer breaks the masonry and the rotating flutes bring out the dust. Masonry drill bits are available from 5mm to 40mm.

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Trowel works 02- Basic hand tool

           Some simple tools are used by the bricklayer and mason in laying bricks, blocks, stones or in plastering work. The bricklayer's tool kit must be used with great care and properly maintained, firstly, because of the safety aspect arid secondly, because the tools can be expensive. When purchasing tools, consideration must be taken on how often the tools will be used. With everyday use, the tools have to be made to be able to withstand the work. Often this is not the case with less expensive tools.
Given below is a list of the tools, how they should be used and properly maintained:

Mason’s trowel Consists of a flat steel blade 250 to 300mm long, post and shank forged as a single piece fixed to a wooden or plastic handle. Used to pick and spread mortar in bed joints and buttering ends of bricks. The blade is widest at its heel and is between 125 – 130mm. Trowels must be well cleaned after use to remove any mortar/cement stuck, wiped cry and stored securely. If not used for a long time the trowel should be lightly oiled to prevent rusting.
Hand Hawk A flat steel plate with a handle at the centre fixed at right angles to the face. Working surface of the blade is shallow grooved with concentric circles to give a coarse surface to hold mortar. The hawk is used mostly when pointing brickwork, and makes it easier to hold the mortar. The mason holds the trowel in one hand and the hawk with mortar in the other. Hawks too need cleaning after use, wiping dry and proper storage.
Line and pins Lines and pins are used in brickwork and blockwork to align bricks/blocks when laying.
Spirit Level This will be the most expensive part of the tool kit. It is used to check the brickwork and that the bricks are level (horizontal) and plumb (vertical). These also come in various sizes. The typical sizes for everyday work are 900 or 1200 mm long. They are available in wood or metal, the metal ones are easier to keep clean as they are easy to wash to remove mortar.
Plumb bob There are two types of plumb bobs. 1.      Centre plumb 2.      Masons plumb The centre plumb is mostly used to transfer positions vertically down and to plumb formwork etc. The mason’s plumb has a brass cylindrical bob and a square wooden stock whose side is exactly the same as the diameter of the bob. This helps to check if the bricks are laid in true vertical alignment.	Centre plumb
Jointers Used for finishing to the joints in brick work. Jointers are made in many shapes to provide half-round, square, triangular or flush joints.
Hammers Also called club hammer or lump hammer. Used with the chisel to cut bricks to required sizes and shapes. Wear eye protection when using brick hammers.
Chisels (or bolsters) Used for cutting bricks to required sizes and shapes. Eye protection must be used at all times it is used. The end of the handle should never be allowed to burr over (or mushroom) after repeated hammering since it is dangerous and could splinter.	Bolster                                     cold chisel
Shovel A shovel is a tool for digging, lifting, and moving bulk materials, such as soil, sand, rubble, gravel, mortar or snow. These are extremely common tools used extensively in construction, agriculture and gardening.
Tampers Tampers are devices used to compact constituents in a mixture such as concrete. In a concrete the constituents are crushed stone, sand, cement and water. When placed in position the concrete is filled with air bubbles and excess water which has to removed to make the concrete dense. Tamping helps in removal of air and excess water. A heavy steel rod can be used as a tamper through repeated poking into the concrete. Sometimes the concrete formwork is tamped with a hammer to compact the concrete.
Screeding rule When concrete is laid in a floor or a floor slab, it has to leveled to give even thickness and a flat level surface. A screed rule is about 1.5m long when operated by a single person, but longer when operated by two persons.
Steel float and wooden float Steel and wooden floats are used to smooth out concrete after it's been poured. They come in different sizes, but a common size is 3 1/2 inches by 15 inches. The steel float has a thick shining steel face while the wooden float has a 12mm (1/2 inch) thick wooden face. Both have a handle on top for easy gripping. After the concrete is all poured, the float will help spread it out evenly and level it off.  Using a float gives the concrete a neat finish.

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Trowel Works 01-Mortar and Concrete

Mortar is the material used in bedding, jointing and pointing bricks and blocks in masonry walling

Constituents of mortar - Mortar is composed of:-

·         Binding material (cement, lime, clay, gypsum, plaster of Paris)

·         Fine aggregate

·         Water

Additives are sometimes mixed to mortar to improve its properties.

Other forms - Fine aggregates mixed with binding material and water also forms some important building finishes such as Plaster, Rendering.

Materials for mortar - General purpose mortar can consist of Sand, Ordinary Portland cement, Water, Plasticizer, Retarder, Accelerator, Pigments or coloring agents and Hydrated lime. Hydrated lime was once commonly used as a binder for mortar but it is rarely used today.

Requirements of a mortar mix – A good mortar mix should have:

·         Adequate compressive strength.

·         Adequate bond strength between mortar and bricks.

·         Durability – resistance to frost and chemical attack.

·         Joints sealed against wind-driven rain.

·         An attractive appearance.

The ability of the mortar to meet these requirements will depend upon the Materials specified for the mix, Workmanship of the bricklayer, Protection of the materials and brickwork against adverse weather.

Mix Proportions - Before mortar can be mixed, the ingredients have to be measured in their correct proportions. The ingredients can be measured by:  Volume or by Weight. Volume mixing can be carried out by hand or by machine, while weight mixing can only be carried out by machine.

Methods of Volume mixing

Materials calculated by volume should be accurately gauged or measured into the correct quantities for each specified mix. The methods used are- Measuring by shovel, Measuring by bucket (or pan) and Measuring by gauge box

Standard Gauge Box

The internal dimensions of a gauge box should be:-

400 x 350 x 250 mm = 0.035 m³

0.035 m³ is the volume of a bag of cement weighing 50 kg.

Mixing by Weight

By using a weight batch mixer, the weight of the aggregate is recorded as it is shoveled into the hopper. This is a more accurate method of batching materials than any of the previously described methods. The materials can be loaded into the hopper while the previously batched materials are being mixed. The weight of materials can be read on a dial by the operator who controls the weight, based on previous calculations for the constituent weights for the required mix. Water is added in liters (1 liter weighing 1kg), after calculating the requirement.

Mixing time - Mixing time depends on the method of mixing - Machine Mixing or Hand Mixing.

Machine Mixing - In general terms, the time of machine mixing should be between two and three minutes. On no account should the mix be allowed to stay in the machine longer because the materials will start to segregate

A concrete and mortar mixer

Cleaning the mixer – It is very important to clean the mixer after day’s work to prevent remnants of mortar or concrete setting and sticking into the inner parts of the mixer. Un-cleaned mixers should not be left overnight. After mixing some sand, coarse aggregate and water should be loaded into the mixer and the mixer turned for about 5 min. This will remove all cement/mortar/concrete stuck onto the blades and the drum thus maintaining a clean machine.

After cleaning the machine should be stored under cover on an elevated level to protect from elements and provide drainage.

Hand mixing

This should take as long as required to ensure that all the particles have been completely integrated together. A high degree of agitation is required when hand-mixing, to ensure that any added plasticizer etc has the necessary effect. Mixed mortar should never be ‘re-tempered’ or ‘knocked up’ with added water because this dilutes the cement/lime element of the mortar which will result in a weaker mix. Mortar is a mixture of the following materials in different combinations: 

                  Sand + Cement + Water

                  Sand + Lime + water

                  Sand + Lime + Cement + Water

                  Sand + Cement + Plasticizer + Water

Typical Mortar Mixes

In work sites, mortar is possibly the least understood and most abused material on the building site. The design strength of the mortar should be determined mainly by the strength of the brick or block to be bedded in it. The mortar strength should roughly match that of the brick or block and in no case should it be stronger than it.

Workability

Mortar will work more easily if the mix contains lime. The more lime the mix contains, the more workable it will be. If the mortar contains cement, it will stiffen more quickly, therefore the more cement within the mix the quicker it will stiffen and set. When mortar of high strength is required, the mix should be composed of cement and sand only.

Design of Mortar Mixes

Mortar mixes are designed to suit certain building requirements. The chart below shows the different mixes and their designated uses which range from 1 to 4. As the mixes progress through the designations of 1 to 4, they become progressively weaker, but with higher lime content they become more tolerant to structural movement.

Designation	Cement, lime with sand	Masonry Cement, sand	Cement, sand with plasticizer	Intended use
1	1:1/4:3			Class A engineering bricks and dense concrete blocks
2	1:1/2:4:4	1:21/2 to 31/2	1:3 or 4	Class B engineering bricks
3	1:1:5 or 6	1:4 or 5	1:5 to 6	Bricks and blocks below DPC level
4	1:2:8 or 9	1:51/2 to 61/2	1:7 to 8	Bricks and blocks above DPC level

Concrete mixes - Concrete mixes are identified in two methods:

1.      By the proportions in which the raw materials are mixed – 1:2:4 (20mm). (1 part cement + 2 parts Fine Aggregate + 4 parts Coarse Aggregate. 20mm denotes the maximum particle size of coarse aggregate). Identifying concrete by this method has disadvantages.

The mix proportion does not specify required strength of concrete and has no control over the quality of concrete.

To overcome this modern day concrete mixes are identified by strength.

2.      Concrete mix by strength - Mixes are identified by the strength which the concrete should possess on setting. These mixes are called Graded Concrete mixes.

Example s –

Grade 10 concrete             (strength 10 mpa)

Grade 15 concrete             (strength 15 mpa)

Grade 20 concrete etc.      (strength 20 mpa)

Concrete mixes and material requirements for a 50kg bag of cement:

Mix	Quantities per 50 kg bag of cement			Use
	Fine aggregate (m³)	Coarse aggregate (m³	App water content (liters)
1:1:2	0.035	0.070	20	Very strong water tight concrete
1:11/2:3	0.053	0.105	22.5	Do
1:2:4	0.070	0.140	25	Reinforced concrete for floor slabs, columns, beams etc
1:3:6	0.105	0.280	35	Foundations, screeds
1:4:8	0.140	0.280	40	Fillings

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