DESIGN AND FABRICATION OF DUAL HACKSAW HACKSAW USING SCOTCH YOKE MECHANISM
Submitted in partial fulfillment for the requirements requirements for the award of the degree of the
BACHELOR OF TECHNOLOGY (MECHANICAL ENGINEERING) By
K.BALAJI
081131201026
K.BASKARAN
081131201038
V.DHANASEKAR
081131201054
R.DHIVAKAR
081131201057 . . . . . . -
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Dr. M.G.R. Educational and Research Institute (Dr. M. G. R. University) Maduravoyal, Chennai – 600 600 095. November 2015.
Dr. M.G.R. EDUCATIONAL AND RESEARCH INSTITUTE Dr. M.G.R. UNIVERSITY DEPARTMENT OF MECHANICAL ENGINEERING CHENNAI – 600 600 095. . . .
. . .
,
-
.
:
BONAFIDE CERTIFICATE .
. :
:
This is to certify that the project work entitled “DESIGN AND AND FABRICATION FABRICATION OF DUAL HACKSAW HACKSAW USING
SCOTCH YOKE MECHANISM ” is a bonafide record of project work done by, K.BALAJI K.BASKARAN V.DHANAASEKAR R.DHIVAKAR
081131201026 081131201038 081131201054 081131201057
Students of B.Tech, (Mechanical) (Mechanical) during the academic year 2014-2015
(Signature of the supervisor)
(Signature of the Head of the
Department)
Mr. G. Rajamahendran, B.E,(M.E),
Professor Mr. M. Ganesan,
Lecturer, Dept. of Mechanical Engineering, Dr. MGR university, .
Dept. of Mechanical Mechanical Engineering Dr. MGR university
Submitted for the project Viva-Voice Examination held on __________
Internal Examiner
External Examiner
ACKNOWLEDGEMENT We wish to expand our sincere thanks and our whole-hearted gratitude to the following persons. At the outset, we would like to convey our grateful thanks to our Chairman Mr. A.C. Shanmugam, our Pro-Chancellor Mr. A.C.S.Arun Kumar , our Vice-Chancellor Dr.Padmanaban. We profusely thank Prof.Mr. Ganeshan , Head of the Department, Mechanical Engineering, for his imperceptible guidance and implications, without which our project would not have been s culpted successfully. We express our heartfelt thanks to Mr. Rajamahendran, for his invaluable guidance, utmost patience, inspirational coordination and constant encouragement in completing this project successfully.
CONTENTS
AIM & OBJECTIVE OF THE PROJECT
AIM OF THE PROJECT
To design and manufacture a working model of Scotch yoke mechanism.
To get a practical exposure manufacturing equipments.
of machine
tools and other
OBJECTIVE The most important objective function is to minimize the cost and overcome problems come into small industry for its rate of production (1) The main objective of this project is to reduce the human effort for machining
various materials. (2) The basic principles of power driven hacksaw or two way hacksaw is Scotch Yoke Mechanism. (3) The objective of this project is to save man power and time in cutting materials in
order to achieve high productivity. (4) By using scotch yoke Mechanism we can operate four hacksaw at same time.
Literature Review:-
Literature Review:-
The vast review of literature will help to understand the concepts, theorems and different factors affecting the performance of machine:3.1 Dharwa Chaitanya Kirtikumar:-
In this paper we study about the designed and developed a multipurpose machine which does not require electricity for several operations like cutting, grinding, etc. this is a human powered machine runs on chain drives mainly with human efforts. But if you wanted to operate this machine by electric power this machine can also does that. It has some special attachment so use both human power as well as electric power. The design is idle for use in the developing world because it doesn’t require electricity and can be built using metal base, chain, pulley, rubber belt, foot pedal electric motor, chain socket. 3.2 R. Subash, K Samuel Jayakaran (2014) :-
In this paper author has designed pedal operated hacksaw machine which can be used for industrial applications and households needs in which no specific input energy or power is needed. This project consist of sprocket arrangement, crank and slider mechanism, and chain drive. In the mechanism, chain derive is directly connected to the hacksaw for the processing of cutting the wooden blocks. The objective of the paper is using the conventional c onventional mechanical process which plays a vital role. The main aim is to reduce the human effort for machining various materials such as wooden blocks, steel, PVC, etc. etc. 3.3 Prof. Nitinchandra, R. Patel, Ravi Thakkar:-
In his paper “Material Selection And Testing Of hacksaw Blade Based On Mechanical Properties” stated that the appropriate saw blade must be selected for
better operation and fine cutting by selecting s electing number of teeth per inch. There are four blades based on materials namely listed below:-
High Carbon Steel Alloy Steel Bi-Metallic Strip High Speed Steel
Out of this four best suitable for cutting hard materials like mild steel bar and aluminum is bi-metallic blade on the basis of properties of materials, wear resistance and cutting performance.
ABSTRACT
ABSTRACT
It is required to machine the round or square rod on different machines to make different machine components like shaft, bolts and screws etc. for a mass production there is need to cut the raw material into number of pieces and this is conventionally perform on a power hack saw or simple hack saw machine which consume more time. To achieve this process within within a less time the the dual hack saw using scotch yoke yoke mechanism is developed.
This project proposes the model of two way hacksaw machine which is able to cut two pieces (may be of same or different material) simultaneously with a very less time consumption. The model using DC motor for its operation. Conversion of rotary motion of dc motor into reciprocating motion is obtained by using scotch yoke mechanism . This model can perform a cutting operation on two different components of different material simultaneously. It becomes very useful in industry due to its efficiency, reliability and compatibility.
WHAT IS OPTIZATION ???
Optimum selection of cutting conditions importantly contribute to the increase of productivity by minimization of production time and the associated costs, therefore utmost attention is paid to this problem in this contribution. Time is the most important parameter in any operation and all the manufacturing firms aim at producing a product in minimum time to reach the customer quickly and enhance the customer satisfaction. This can be achieved by using optimization techniques. The success of an optimization technique does not lie in its complexity but the time in which it provides a solution to the manufacturing firms.
PROBLEM STATEMENT
PROBLEM STATEMENT
To convert rotary motion into Reciprocatory motion in a simple harmonic manner.
To build a working model which can be fabricated easily using the available tools and machinery.
INTRODUCTION
INTRODUCTION The Scotch yoke is a mechanism for converting c onverting the linear motion of a slider into rotational motion or vice-versa. The piston or other reciprocating part is directly coupled to a sliding yoke with a slot that engages a pin on the rotating part. The shape of the motion of the piston is a pure sine wave over time given a constant rotational speed. This mechanism is an inversion of the double slider crank mechanism. mechanism. The inversion is obtained by fixing either the link 1 or link 3. In I n Fig, link 1 is fixed. In this mechanism, when the link 2 (which corresponds to crank) rotates about B as centre, ce ntre, the link 4 (which corresponds to a frame) reciprocates. The fixed link 1 guides the frame. frame.
Other inversions inversions of the double slider crank mechanism include Oldham coupling coupling and elliptical trammel. History
This linkage is being called by a Scotsman in 1869 a "crank and slot-headed slot-headed sliding rod“ But now it is known as a Scotch yoke because, in America at least, a "Scotch" was a slotted bar that was slipped under a collar on a string of well-drilling tools to support them while a section was being added In 1940 Russell Bourke applied this mechanism to the internal combustion engine called Bourke 30 engine
SIMPLE HARMONIC MOTION
u
v
Suppose crankshaft is rotating at an angular velocity
‘Ω’.
If r is is the radius of the crank then, Tangential velocity,
α
x-axis
v= ‘rΩ’ .
From the mechanism we have the following relation; Component of tangential velocity in Y-direction is given by; u = = Reciprocating velocity of U-Slot. If α is the angle made by the tangential velocity with X-Axis at any point of time, Component of tangential velocity in Y direction is u = r Ωsin α α. u = v.sin α α So, velocity of U-Slot= r Ωsin α α. As a result, Velocity of U-Slot is a sine function of
α .
Now as we know,α is is directly proportional to time. This implies velocity of U-Slot is a sine function of time. Hence, the motion of U-Slot is a simple harmonic motion. Advantage of SHM The sinusoidal motion, cosinusoidal velocity, and sinusoidal acceleration (assuming constant angular velocity) results in smoother operation of the mechanism.
MECHANISM IIn mechanical construction, the means employed to transmit and modify motion in a machine or any assemblage of mechanical parts. The chief characteristic of the mechanism of a machine is that all members have constrained motion; i.e., the parts can move only in a determinate manner relative to one another In In Scotch Yoke Mechanism The Scotch yoke is a mechanism for converting the linear motion of a slider into rotational motion or vice-versa. The piston The piston or other reciprocating part is directly coupled to a sliding yoke sliding yoke with a slot that engages a pin on the rotating part. The shape of the motion of the piston is a pure sine wave over time given a constant rotational constant rotational speed.
Figure 1.1 Sectional view of Scotch yoke mechanism
In m , the means employed to transmit and modify motion in a machine or any assemblage of mechanical parts. The chief characteristic char acteristic of the mechanism of a machine is Figure 1Front view of Scotch Yoke Mechanism construction
that ALL
CONSTRUCTION
CONSTRUCTION
This unit consists of following parts ; 1. 24VDC motor with built in gear box 2. 24 VDC power supply 3. Two numbers of hacksaw with blade 4. Crank disc with motor coupler 5. Yoke 6. M.S. Fabricated stand
1. 24VDC MOTOR WITH BUILT IN GEAR BOX; This DC motor is shunt type 24V DC motor. motor. This motor motor is having built in type speed speed reduction gear box unit. It has high torque torque and low speed capacity. The electrical supply to the the motor is from 24V DC power supply. The DC Motor drives the Crank wheel mechanism.
2. 24 VDC power supply 12 – 0 -12 V AC step down transformer is used to stepdown 230V AC to e.,,A 12 – e.
12V AC or 24 V AC .This 24V AC supply is converted converted to 24V DC using four rectifier diodes. .This .This voltage is used for supply for the DC motor. motor.
STEP DOWN TRANSFORMER:
When AC is applied to the primary winding of the power transformer, it can either be stepped stepped down or stepped up depending on the value value of DC needed. In our circuit the transformer of 230V/12-0-12V is used to perform the step down operation where a 230V AC appears as 24V AC across the secondary winding. Apart from stepping down voltages, it gives isolation between the power source and power supply circuitries. RECTIFIER UNIT:
In the power supply unit, rectification is normally achieved using a solid state diode. Diode has the property that will will let the electron flow easily in one direction at proper biasing condition. As AC is applied to th e diode, electrons only flow when the anode and cathode cathode is negative. negative. Reversing the polarity polarity of voltage will not permit permit
electron flow. A commonly commonly used circuit for supplying large amounts amounts of DCpower is the bridge rectifier. A bridge rectifier of four diodes (4 x IN4007) are used to achieve full wave rectification. rectification. Two diodes will conduct during the negative cycle and the other two will conduct during the positive half cycle, and only one diode conducts. At the same time one of the other two diodes conducts for the negative voltage that is applied from the bottom bottom winding due to the the forward bias for that diode. In this circuit due to positive half cycle D1 & D2 will conduct to give give 0.8V pulsating DC. The DC output has a ripple frequency of 100Hz. Since each alteration alteration produces a resulting output pulse, frequency = 2 x 50 Hz. The output obtained obtained is not a pure DC and therefore filtration has to be done. The DC voltage appearing across the output terminals of the bridge rectifier will be somewhat less than 90% of the applied rms r ms value. Normally one alteration of the input voltage voltage will will reverse the polarities. polarities.
Opposite ends of the transformer will will
therefore always be 180 degree out of phase with with each other. For a positive cycle, two two diodes are connected to the positive voltage at the top winding.
FILTERING CIRCUIT:
Filter circuits which is usually capacitor acting as a surge arrester always follow the rectifier unit. This capacitor is is also called as a decoupling capacitor
3. Two numbers of hacksaw with blade The sawing machine is a machine tool designed to cut material to a desired length or contour. It functions by drawing a blade containing cutting teeth through the work piece. The sawing machine is faster and easier than hand sawing and is used principally to produce an accurate square or mitered cut on the work piece .
The power hacksaw and the handsaw are two com mon types of sawing machines used to cut metal in the machine shop .The power hacksaw uses a reciprocating (back and forth) cutting action similar to the one used in a hand hacksaw. The power hacksaw is used for square or angle cutting of stock, The band saw uses a continuous band blade. A drive wheel and an idler wheel support and drive the blade.
Fig 11 Hacksaw
HACKSAW BLADE The selections of the blade depend upon the materials which have to cut by the hacksaw. These blades are ideal to use when the work is held securely and the blade is not subjected to bending and twisting stresses. They hold the edge when cutting hard to machine Alloys, maintaining straightness of the cut. The blades are uniformly hardened throughout.
The most common blade is the 12 inch or 300 mm length. Hacksaw blades have two holes near the ends for mounting them in the saw frame and the 12 inch / 300 mm dimension refers to the center to center distance between these mounting holes. 12 Inch Blade Hole to Hole: 11 7/8 inches / 300 mm Overall blade length: 12 3/8 inches / 315 mm (not tightly controlled) Mounting Hole diameter : 9/64 to 5/32 inch / 3.5 to 4 mm (not tightly controlled) Blade Width: 7/16 to 33/64 inch / 11 to 13 mm (not tightly controlled) Blade Thickness: 0.020 to 0.027 inches / 0.5 to 0.70 mm (varies with tooth pitch and other factors)
The hacksaw is used to cut steel and other metals. It can also be used to cut plastics, although it is not normally used to cut Woods. It is sometimes called an adjustable hacksaw because the length of the frame can be altered to hold blades of Different sizes. Blades are supplied in two lengths, 250mm and 300mm. If the adjusting screw is unscrewed, the frame can Be pushed into the handle so that the smaller blades fit the hacksaw. Blades are also described by the number of teeth per inch (TPI). Blades very fine.
4. crank disc with motor coupler and yoke The scotch yoke mechanism is constructed with iron bars. Here the crank is made in some length and the yoke is also made using the same material. It is noted that the
minimum length of the yoke should be double the length of the crank. The crank and yoke is connected with a pin. Iron bars are welded to both sides of the yoke to get the reciprocating motion. The yoke with the iron bars is fixed on the base stand board with the help of sleeve bush . Now the crank is welded to to the end of the the shaft of the motor. Now the pin on the crank is connected to the yoke. The pin used to connect yoke and crank is a bolt .
6.M.S. Fabricated stand The M.S.Stand is shown in figure. It is made in L angle channel 3mm thickness and 600 mm height. The scotch yoke mechanismwith hacksaw units are is mounted at the top. M.S.FABRICATED STAND
yoke
Crank disc
WORKING PRINCIPLE
WORKING PRINCIPLE
When the power is supplied to the 24v Dc motor, shaft and crank attached to the shaft start rotating. As the crank rotates the pin slides inside the yoke and also moves the yoke forward. When the crank rotates through in clockwise direction the yoke will get a displacement in the forward direction. The maximum displacement will be equal to the length of the crank. When the crank completes the next of rotation the yoke comes back to its initial position. For the next of rotation, yoke moves in the backward direction. When the crank completes a full rotation the yoke moves back to the initial position.. The yoke is connected to reciprocating rod with hacksaw frame on both sides. Two hacksaw frames are reciprocated to cut the PVC tube which is screwed in the table.
ADVANTAGES AND DISADVANTAGES
ADVANTAGES AND DISADVANTAGES
The advantages compared to a standard crankshaft and connecting rod setup are:
High torque output with a small cylinder size. Fewer moving parts. Smoother operation. Higher percentage of the time spent at top dead centre (dwell) improving engine efficiency. In an engine application, elimination of joint typically served by a wrist pin, and near elimination of piston skirt and cylinder scuffing, as side loading of piston due to sine of connecting rod angle is eliminated. Time saving as compared to manual and single way hacksaw machine. No input power is required. At a single point of time it can able to cut more than one job of any required size.
It is easily portable.
The disadvantages are:
Rapid wear of the slot in the yoke caused by sliding friction and high contact pressures. Lesser percentage of the time spent at bottom dead centre reducing blow down time for two stroke engines. The shape of the motion of the piston is a pure sine wave over time given a constant rotational speed.
Applications:
1. Cutting of two metal piece at the same s ame time. 2. Cutting of wooden workpieces. 3. Cutting of plastic materials and PVC pipes.
RESOURCES USED Materials
Dimensions
Mild steel plates
1. 25 mmX25mm x 3 mm L angle 2. 50 mm x 2.5 mm M.S.flat
Mild Steel Rod
Mild steel hollow pipe
Mild steel square pipe
EQUIPMENT USED 1. Lathe Machine 2. Drilling machine 3. Grinding machine 4. Power tools 5. Power Hacksaw Electric arc welding machine
1. Φ10 mm 2. Φ20 mm Φ12 mm (internal) Φ14 mm (external) 25 mm x 25 mm (external) Thickness-2 mm
DESIGN AND CALCULATIONS
CALCULATIONS
Good science project does not stop with building a motor. It is very important to measure different electrical and mechanical parameters of your motor and calculate unknown values using the following helpful formulas. We will use the International System of Units (SI). This is modern metric system that is officially accepted in electrical engineering in the USA. One of the most important i mportant laws of physics is the fundamental Ohm’s Law. It states that current through the conductor is directly proportional to applied voltage and is expressed as: I = V / R
where I – I – current, current, measured in amperes (A); V – applied applied voltage, measured in volts v olts (V); R – – resistance, resistance, measured in ohms (Ω). This formula could be used in many cases. You may calculate the resistance of your motor by measuring the consumed current and applied voltage. For any given resistance (in the motors it is basically the resistance of the coil) this formula explains that the current can be controlled by applied voltage. The consumed electrical power of the motor is defined by the following formula: Pin = I * V
where Pin – Pin – input input power, measured in watts (W); I – current, current, measured in amperes (A); V – applied applied voltage, measured in volts (V). Motors supposed to do some work and two important values define how powerful the motor is. It is motor speed and torque – the turning force of the motor. Output mechanical power of the motor could be calculated by using the following formula: Pout = τ * ω
where Pout – Pout – output output power, measured in watts (W); τ – torque, – torque, measured in Newton meters (N•m); ω – angular angular speed, measured in radians per second (rad/s). It is easy to calculate angular speed if you know rotational speed of the motor in rpm: ω = rpm * 2π / 60
where ω – angular angular speed, measured in radians per second (rad/s); rpm – rpm – rotational rotational speed in revolutions per minute; π – mathematical mathematical constant pi (3.14). 60 – 60 – number number of seconds in a minute. If the motor has 100% efficiency all electrical power is converted to mechanical energy. However such motors do not exist. Even precision made small industrial motors such as one we use as a generator in generator kit have maximum efficiency of 50-60%. Motors built from our kits usually have maximum efficiency of about 15% (see Experi Experiments ments section on how we estimated this). Don’t be disappointed with 15% maximum efficiency. All our kits are intended for education and not designed for real applications. This efficiency is not bad at all – all – it it is actually much better than most of other self made designs on Internet can provide. The motors have enough torque and speed to do all kinds of experiments and calculations. Measuring the torque of the motor is a challenging task. It requires special expensive equipment. Therefore we suggest calculating it.
Efficiency of the motor is calculated as mechanical output power divided by electrical input power: E = Pout / Pin
therefore Pout = Pin * E
after substitution we get τ * ω = I * V * E τ * rpm * 2π / 60 = I * V * E
and the formula for calculating torque will be τ = (I * V * E *60) / (rpm * 2π)
Connect the motor to the load. Using the motor from generator kit is the best way to do it. Why do you need to connect the motor to the load? Well, if there is no load – there is no torque. Measure current, voltage and rpm. Now you can calculate the torque for this load at this speed assuming that you know efficiency of the motor. Our estimated 15% efficiency represents maximum efficiency of the motor which occurs only at a certain speed. Efficiency may be anywhere between zero and the maximum; in our example below 1000 rpm may not be the optimal speed so the for the sake of calculations you may use 10% efficiency (E = 0.1). Example: speed is 1000 rpm, voltage is 6 Volts, and current is 220 mA (0.22 A): τ = (0.22 * 6 * 0.1 * 60) / (1000 * 2 * 3.14) = 0.00126 N•m
As the result is small usually it is expressed in milliNewton meters (mN•m). There is 1000 mN•m in 1 N•m, so the calculated torque is 1.26 mN•m. It could be also
converted further to still common gram force centimeters (g-cm) by multiplying the result by 10.2, i.e. the torque is 12.86 g-cm. In our example input electrical power of the motor is 0.22 A x 6 V = 1.32 W, output mechanical mech anical power is 1000 rpm x 2 x 3.14 x 0.00126 N•m /60 = 0.132 W. Motor torque changes with the speed. At no load you have maximum speed and zero torque. Load adds mechanical resistance. The motor starts to consume more current to overcome this resistance and the speed decreases. If you increase the load at some point motor stops (this is called stall). When it occurs the torque is at maximum and it is called stall torque. While it is hard to measure stall torque without special tools you can find this value by plotting speed-torque graph. You need to take at least two measurements with different loads to find the stall torque. How accurate is the torque calculation? While voltage, current and speed could be accurately measured, efficiency of the motor may not be correct. It depends on the accuracy of your assembly, sensor position, friction, alignment of the motor and generator axles etc. If you want to get meaningful numbers you might use a second generator kit as explained in Torque and Efficiency Calculation section. Speed, torque, power and efficiency of the motors are not constant values. Usually the manufacturer provides the following data in a table like this one (sample data from one of the motors used in generator kit):
Also the manufacturers usually provide power curves for the motor at nominal voltage:
These curves are generated by plotting motor speed, consumed current, and efficiency as functions of the motor torque. Sometimes there might be also a curve representing mechanical output power. As you can see from the graph speed and current are linear functions of torque so you might need only two measurements to draw these graphs. Efficiency and power will need more data. Usually for small motors maximum power is at 50% of stall torque (approximately 50% of no load speed). Maximum efficiency may be 10-30% of motor stall torque (70-90% of no load speed). While it is technically better to follow the same format and create similar curves for your motor it is not absolutely necessary for a good science project. You may take all
measurements, calculate unknown values and plot the graphs where for example speed and torque are represented as functions of applied voltage or current etc.
SCOTH YOLK MECHANISM THEORY
It is an inversion of double slider crank mechanism The Scotch yoke is a mechanism for converting the linear motion of a slider into rotational motion or vice-versa. The piston or other reciprocating part is directly coupled to a sliding yoke with a slot that FIGURE 1.1 engages a pin on the rotating part. The shape of the motion of the piston is a pure sine wave over time given a constant rotational speed.fig 1.1 illustrates a simple scotch yolk mechanism
Comparison of scotch yolk with Slider crank mechansim
The advantages compared to a standard crankshaft and connecting rod setup are:
Fewer moving parts.
Smoother operation.
Higher percentage of the time spent at top dead center (dwell) improving theoretical engine efficiency of constant volume combustion co mbustion cycles, though actual gains have not been demonstrated.
In an engine application, elimination of joint typically served by a wrist pin, and near elimination of piston skirt and cylinder scuffing, as side loading of piston due to sine of connecting rod angle is eliminated. Applications
This setup is most commonly used in control valve actuators in high pressure oil and gas pipelines. It has been used in various internal combustion engines, such as the Bourke engine, SyTech engine, stirling,and many hot air engines and steam engines. Refer to fig 1.2 Experiments have shown that extended dwell time will not work well with constant volume combustion (Otto, Bourke or similar) cycles.Gains might be more apparent using a stratified direct injection (diesel or similar) cycle to reduce heat losses.
DESCRIPTION OF HACKSAW MACHINE
3.1 Types of Hacksaw Machine
(1) Light duty hacksaw machine. (2) Hydraulic hacksaw machine. (3) Power hacksaw machine. (4) Circular band hacksaw machine. (5) Horizontal swing type band saw machine. (6) Band hacksaw machine. (7) Jigsaw machine. (8) Universal type circular hacksaw machine. (9) Double column band saw machine. (10) Chain saw circular machine.
3.1.1 Light duty hacksaw machine
Your quest for finest quality hydraulic hacksaw machine ends with us. We are recognized as one of the chief power hacksaw machine manufacturers of India. The hacksaw machine manufactured by us is used at length in number of industries.
Fig 3.1.1 Light duty hacksaw machine
Features of Light Duty Hacksaw Machine
(1) A quality ‘Self -Centering Vice’ with perfect grip. (2) Gear and hydraulic are oil submerged. (3) Full function coolant pump with fitting. (4) Rigid and heavy M.S. fabricated body.
3.1.2 Hydraulic Hacksaw Machine
We supply a huge collection of precisely-engineered hydraulic hacksaw machinewhich is very effective in performing a series of cutting operations in workshops with its easy automation.
Acclaimed among the established hacksaw machine suppliers, we offer these machines in different cutting capacities, sizes, models etc. As per the needs and specifications of our end customers.
Fig 3.1.2 Hydraulic hacksaw machine
Features of Hydraulic Hacksaw Machine
(1) High productivity. (2) Corrosion-resistance. (3) Trouble free service. (4) Optimum performance.
(5) Long lasting.
3.1.3 Power Hacksaw Machine
Power hacksaw machine fabricated by us is precision engineered so as to meet themodern demands of several industries. Due to their smooth & swift functioning ability they are able to operate in a spontaneous way which aids the worker in consistently carrying his work with ultimate efficiency.
Fig 3.1.3 Power hacksaw machine
Features of Power Hacksaw Machine
(1) Fine cutting. (2) Longer service life. (3) Self lubrication. (4) Infinitely variable feed rate. (5) Cutting arm of high tension bearing capacity.
3.1.4 Circular Band Saw Hacksaw Machine
Supreme efficiency and long term durability are blended in Circular Band SawMachine provided by us. Being durable and rendering unparalleled service, band saw machine manufactured by us is gaining lot of popularity in appreciation of customer's requirement. We offer circular band saw machines in varied sizes ranging from 10' to 14'.
Fig 3.1.4 Circular band saw hacksaw machine
Types of Band Saw Machines
(1) Double column construction horizontal band saw machines. (2) Vertical Band Saw Machines. (3) Circular Sawing Machines.
Features of Circular Band Saw Hacksaw Machine
(1) LM Guide way 1000 meter length. (2) Ball screw. (3) Servo motor. (4) S.S. Fabricator safety cover.
(5) Harden plate for griping the job.
3.1.5 Horizontal Swing Type Band saw Machine
Horizontal swing type band saw is manufactured by us in integral front and rear bed design. The entire assortment of these machines has large cross section of swing frame and ensures high speed productivity. All these horizontal swing type band saw machines are widely demanded in engineering industries for various cutting applications.
Fig 3.1.5 Horizontal sawing type band saw hacksaw machine
Features of Horizontal Swing Type Band saw Machine
(1) High speed. (2) Heavy duty. (3) High productivity. (4) Integral front & rear bed design. (5) Large cross section of swing frame.
3.1.6 Band Hacksaw Machine
Very useful for preparing specimen of big size in anatomy and meat departments. Fitted with large moving table and extension table operated on four ball bearing rollers.
Used extensively in the meat packing, and wholesale fish industry, for handling swordfish and large halbutes etc.
Fig 3.1.6 Band hacksaw machine
Features of Band Hacksaw Machine
(1) Cast iron table with trunnion system. (2) Tool holder for easy handling of tools. (3) Enclosed cabinet support for storage of extra blades. (4) Adjustable blade guide bearings.
(5) Heavy-duty fence with resaw bar and others.
3.1.7 Jigsaw Machine
The top maker of jig saws is Skill, A jig saw is both versatile and very safe to use. Ajigsaw combines the functions of band saw, a router, circular saw, and a scroll saw into one portable tool.
There are both corded jig saws and cordless jig saws - each offering its advantagesand disadvantages.
The corded jig saws are extremely convenient in remote areas and are best suited to cut wood and wood products. They are available from 12 to 18 volts and higher voltage equates to a battery that lasts longer.
Fig 3.1.7 Jigsaw machine
Features of Jigsaw Machine
(1) Sturdy model and Vibration free. (2) Graded heavy duty casting body. (3) Totally dust proof oil immersed. (4) Gear box and main parts made of alloy steel.
(5) Easy & smooth trouble free operation.
3.1.8 Universal Type Circular Hacksaw Machine
Universal Type Circular Saw machines which are used for paneling, cutting or ripping lumber.
It is generally utilized in projects where fast straight cuts of respective precision are needed through heavier material.
This wonderful circular saw machine is available in two different ways which are automatic circular saw and semi-automatic circular saw.
Fig 3.1.8 Universal type circular hacksaw machine
Features of Universal Type Circular Hacksaw Machine
(1) Fast straight cuts of respective precision. (2) It is also available in automatic circular saw and semi-automatic circular saw.
3.1.9 Double Column Band Saw Machine
Double Column Band Saw Machine is equipped with rigid chrome plated double column, separate electrical panel, infinitely variable feed with flow control valves and power driven wire brush.
The range of band saw machine is hydraulically h ydraulically operated dual clamping system. Its application is used in engineering industry and construction industry.
Fig 3.1.9 Double column band saw machine
Features of Double Column Band Saw Machine
(1) Automatic height control. (2) Power driven chip brush for chip removal. (3) Manual band tension. (4) Split front vice. (5) Complete hydraulic. (6) Length setting can be done. (7) Complete electrical system integrated. (8) Complete coolant system integrated.
3.1.10 Chain Saw Circular Machine
Available with us is an extensive range of Chain Saw Machines. Manufactured using high quality raw material, which facilitates fabrication of high quality products, our range is ideal for square whole operation.
Chain Saw Machines is specially designed for square hole in wood for doors and windows. This machine is used for mass production of square hole operation.
Fig 3.1.10 Chain saw circular machine
Features of Chain Saw Circular Machine
(1) Highly efficient. (2) Easy to operate.
(3) Accurate dimension.
3.2 Construction of Hacksaw Machine
Hacksaw Machines offered by us are used for metal cutting ranging from transportable model to giant size machine. Owing to smooth & speedy functioning abilities, these hacksaw machines operations spontaneously for aiding the worker in consistently carrying his work with ultimate competence.
Fig 3.2 Construction of hacksaw machine
(a) Bed: - The bed is available as a single piece casting. It has wide rigid casting for
the collection of coolant, swarf and also houses the V-belt device.
(b) Saw Frame: - The rigid saw frame ensures a square & parallel cut & the cut takes
place on the backward pull stroke. To prevent the wear of the blade, it is hydraulically lifted out of contact with work place on the forward stroke up.
There are two type of saw frame:
Solid frame
Adjustable frame
(1) Solid Frame: - In this type, only one particular standard length of blade can be
used with this frame.
Fig 3.2.1 Solid frame
(2) Adjustable Frame: - In this type different standard lengths of blades can be fitted
to this frame.
Fig 3.2.2 Adjustable frame
(c) The Drive: - The drive is attached through V-Pulleys with provision to adjust the
complete tension of the V-Belts. The shafts are fitted with ball bearings and taper and ball bearings to eliminate friction.
(d) Speed: - Specific speeds have been provided for different kind of metals in order
to make it suitable. High speed for metals like mild steel, brass, copper etc. and low speed for cast iron.
(e) Feed saw: - Two levers are provided to hydraulically control the Feed Saw at the
dash-pot. One controls the rate of feed and the other enables the bow slide to be raised or lowered and after the completion of the cut, the motor gets automatically switched off.
(f) Vice: - The vice is rigid construction. It has two jaws, one jaw remains fixed and
the other is adjusted according to the size of the material to be cut.
(g) Coolant: - A coolant tank is enclosed within the base of machines with constant
speed to supply continuous cooling to the saw blade.
(h) Electricals: - A Push button starter is fitted with an adjustable trip mechanism that
helps in stopping the machine soon when the blade is clear from the work at extra cost.
Features of Hacksaw Machine
Power efficiency.
High productivity.
Superb performance.
High operational fluency.
Sturdy and robust design.
3.3 Hacksaw Blades
The hacksaw blade consists of different parts:
2 pin holes
Center line
Side
Back edge
Fig 3.3 Hacksaw blade
3.3.1 Characteristics of Hacksaw Blade
The hacksaw blade has 2 main characteristics:
(1) Teeth pitch which is the number of teeth per 25 mm.
Fig 3.3.1 Teeth pitch
(2) Blade length which is the length between the centers of its pin holes.
CONCLUSION AND FUTURE RESEARCH
CONCLUSION AND FUTURE RESEARCH
From above discussion we conclude that model of two way hack saw is helpful to overcome the problems of conventional hack saw with high efficiency it’s easy to operate and simple in construction. By increasing the motor power and dimensions of eccentric cam the size of material to be cut can be increased. By using limit switches or sensors Automatic feeding mechanism for material can be introduced. Automatic lifting up mechanism for frame when cutting operation can be by using hydraulic piston and cylinder.
CONCLUSION
CONCLUSION
The scotch yoke mechanism is made and its advantages and disadvantages are discussed. Its motion characteristics are studied. It is concluded that this mechanism is a good choice to convert rotating motion into reciprocating motion because of fewer moving parts and smoother operation. It can be used in direct injection engines like diesel engines, hot air engines. In this project report we provide an overview of the issues concerning different aspects of machines machines using scotch yoke mechanism .The project report focus on the principle of scotch yoke mechanism and its application. application.
REFERENCE
REFERENCE
1.
MECHANICS OF MATERIALS - Fourth Edition in SI Units Ferdinand P. Beer E. Russell Johnston, Jr. John T. DeWolf McGraw-Hill
(1) Build a power hacksaw with vise, Authors: - Vincent Gingery
(2) D.V.Sabarinanda, Siddhartha, B. SushilKrishnana, T.Mohanraj , “Design and Fabricati on Of Automated Hacksaw Machine”, International Journal of Innovative Research in Science, Engineering and Technology, ISSN (Online): 2319-8753, volume 3, April 2014.
(3) R. Subhash, C.M. Meenakshi, K. SamuelJayakaran, C. Venkateswaran, R. Sasidharan, “Fabrication pedal powered hacksaw using dual
(4) Prof. Nitinchandra R. Patel, Mohammad A.Vasanwala, Balkrushna B. Jani, Ravi Thakkar, Miteshkumar D. Rathwa,”Material selection and testing of hacksaw blade based on mechanical Properties”, International International Journal of Innovative Research in Science, Engineering and Technology, ISSN: 2319-8753, volume 2, Issue 6, June 2013.
