Holding Devices - Week 6 Lecture Module PDF

1 LEARNING GUIDE Week No.: __6__ TOPIC: HOLDING D...

1 LEARNING GUIDE Week No.: __6__ TOPIC: HOLDING DEVICES I. EXPECTED COMPETENCIES Upon completing this Learning Module, the student will be able to: a. to understand the importance of Holding devices used in Bench Work b. to identify the different types of vise commonly used in Bench Work c. to be able to know the Do’s and Don’ts when working with Holding Devices II. CONTENT/TECHNICAL INFORMATION Bench work has its own essential position in all engineering works. In the mechanized workshops, where most of the work is carried out on an automatic machine, while bench work has its own importance. The jobs can be finished to a fairly good degree of accuracy through machining operations to be done on them to finished to the desired accuracy. A fitter’s work is unavoidable when different parts are to be assembled in position after they have been finished. Alignment of machine parts, bearing, engine, slide valves and similar other works call for a fitter’s work. Reconditioning and refitting of machines and machine parts cannot be done without a skilled fitter. All the above types of works require the use of a large number of hand tools and a fitter must have good working knowledge of all these tool and instruments. Holding tools are also known as Work Holding devices in the Bench Work. They are used to hold all types of components between jaws (Fixed Jaw and Movable Jaw). Most vises can be used for a wide variety of work. Select the most suitable vise which is strong enough for the work.  Wear safety glasses or goggles, or a face shield (with safety glasses or goggles) when using striking tools or power tools on a workpiece held by a vise.  Attach a vise securely. Place bolts in all the holes in the base of the vise. Use lock washers under the nuts.  Mount a vise so that the stationary jaw projects slightly beyond the edge of the workbench. This allows long work to be clamped in the vise without interference from the edge of the workbench.  Ensure that the workbench is firmly secured to its base. This module is a property of Technological University of the Philippines Visayas and intended for EDUCATIONAL PURPOSES ONLY and is NOT FOR SALE NOR FOR REPRODUCTION.  2  Check the vise for cracks or other damage before clamping a workpiece in it.  Use a vise large enough to hold the work without strain.  Place the workpiece in the vise so that the full clamping surface of the jaw supports the workpiece  Keep the workpiece in the vise close as possible to the jaws to prevent vibration when sawing, filing, etc.  Support the end of extra-long work with an adjustable stand, saw horse, or box rather than putting extra strain on the vise.  Keep all threaded and moving parts clean, oiled and free of chips and dirt.  Use jaw liners in a vise where there is any possibility of marking the work.  Replace a bent handle and worn jaw inserts. What should I not do?  Do not weld the base of the vise to any metal.  Do not repair a vise by welding or brazing.  Do not try to bend a heavy rod in a light vise.  Do not cut into the jaws.  Do not apply heavy pressure at the corner of the vise jaws.  Do not use a handle extension (e.g., a pipe) for extra clamping pressure.  Do not hammer on the handle to tighten beyond hand pressure.  Do not use the jaws of the vise as an anvil.  Do not use any vise that has the slightest crack.  Do not unscrew or open the jaws of the vise wider than they were designed to be used. The Various Work holding devices are  Workbench  Bench Vise  Pipe Vise  Hand Vise  Toolmakers Vise This module is a property of Technological University of the Philippines Visayas and intended for EDUCATIONAL PURPOSES ONLY and is NOT FOR SALE NOR FOR REPRODUCTION.  3 Work Bench:  It is used to hold various components on its surface.  It also gives support to a human while performing various operations. Bench Vise: It is firmly fixed to the bench with the help of nuts and bolts. It consists of a cast Iron body and cast iron jaws. Two jaw plates are fitted on both the jaws. The holding surface of the jaw plates is knurled in order to increase the gipping. Jaw plates are made up of carbon steel and are wear resistant. One jaw is fixed to the body and the second slides on a square threaded screw with the help of a handle. The jaws are opened up to required length; job is placed in the two jaws and is fully tightened with the help of handle. Handle is used to move the movable jaw  Bench Vise is a holding tool which is used to hold the specimen or the workpiece between the two jaws. The Parts of Bench Vise are: 1. Jaws o Fixed Jaw o Movable Jaw 2. Body 3. Handle Parts of Bench Vise Jaws: The Jaws are used to hold the workpiece by rotating the handle. In that, one jaw is fixed and the other is movable. This module is a property of Technological University of the Philippines Visayas and intended for EDUCATIONAL PURPOSES ONLY and is NOT FOR SALE NOR FOR REPRODUCTION.  4 Rankin Kennedy C.E, Fitter’s metalworking bench vise A “Parkinson’s Perfect” brand, with quick- release screw Scans from ‘The Book of the Motor Car’, Rankin Kennedy C.E., 1912 Body: All the parts like a handle, jaws etc.are connected to the body of a bench vise. Handle: If the handle is rotated in CW direction, then the work-piece is fixed between two jaws. If the handle is rotated in CCW direction, then the workpiece is loosened from the jaws. Pipe Vise:  It is similar to Bench Vise but here the Circular/Cylindrical components are to be placed in between the upper and lower jaws due to the curvature of existing jaws.  The Parts of pipe vise are handle, screw spindle, movable and fixed jaws, etc. This module is a property of Technological University of the Philippines Visayas and intended for EDUCATIONAL PURPOSES ONLY and is NOT FOR SALE NOR FOR REPRODUCTION.  5 Hand vise:  A hand vise is a tool that is designed to hold the workpieces in between the jaws.  The wingnut is tightened in CW direction to hold the w/p and loosened in CCW direction. Tool maker’s vise:  The screw-driven movable jaw for applying clamping force.  Made from hardened alloy steel.  Single piece construction with V-grooved Jaws.  All surface including Jaws and Base are precision ground square and  parallel. https://www.pinterest.ph/FredaLaRue1/toolmaker/ This module is a property of Technological University of the Philippines Visayas and intended for EDUCATIONAL PURPOSES ONLY and is NOT FOR SALE NOR FOR REPRODUCTION.  6 PROGRESS CHECK Multiple Choice 1. Vises should always be secured to the workbench with screws A. True B. False 2. The ----------- is used to hold the material firmly during cutting and shaping operations. a) Bending machine b) Clamping machine c) Notching machine d) Bench-vise e) None of the above 4. 1 inch diameter Copper tubes are best hold on a tool makers vise. A. True B. False 5. Work benches are usually 1 meter in height. A. True B. False 6. Work bench should be firmly secured on the floor if possible be bolted. A. True B. False 7. It is considered the third hand of a worker. A. Pliers B. Locking Pliers C. Machinist vise D. Shears 8. If you notice stress fractures on the bench vise try to weld it your self immediately for repairs. A. True B. False 9. A vise use to hold small objects tight while grinding, drilling, filing, hammering, sanding, shaping, etc. Jaws have vertical and horizontal V grooves for holding round objects. A. Tool maker’s vise B. Pipe vise C. Bench vise D. Hand Vise 10. When tightening your work on a bench vise especially pipes, to increase handle leverage use a pipe as an extension. A. True B. False REFERENCES Occupational Safety and Health Administration (2020). Evacuation Plans and Procedures eTool: Emergency Standards to Portable Fire Extinguishers. https://www.osha.gov/SLTC/etools/evacuation/portable.html Dixon,R. (1981). BenchWork: Delmar Laknepally, V., Narsampet, M. (2020). Engineering Workshop Laboratory Manual This module is a property of Technological University of the Philippines Visayas and intended for EDUCATIONAL PURPOSES ONLY and is NOT FOR SALE NOR FOR REPRODUCTION.  7 Department Of Mechanical Engineering. Retrieved From: Engineering-Workshop-i-Lab- Manual_1st%20year.pdf LEARNING GUIDE Week No.: __7_ TOPIC: CHISELING I. EXPECTED COMPETENCIES Upon completing this Learning Module, the student will be able to: a) to understand the importance of chiseling and how does it works b) to explain the basic principles of how cold chisel are made, how to take care of them and usage safety. c) to identify the different classifications of cold chisel II. CONTENT/TECHNICAL INFORMATION Chiseling is a term applied to benchwork that describes metal cutting process by a wedge shaped cutting tool called a cold chisel. How it works: Cutting process can be accomplished in any of the three methods namely; parting or dividing, chipping, and shearing. Parting or Dividing: Parting operation is the process of allowing the cutting edge of the cold chisel to penetrate into the workpiece by driving the head vertically with several blows of the hammer. The force applied on the head of the cold chisel causes the material to yield at the point of penetration and giving way to the cutting edge until parting is accomplished. The utilization of the applied force depends on the size of the lip angle. Lip Angle Small Normal Large Force \ Required least medium high Ease of Penetration easy moderate hard Risk of Breakage large less least Application soft medium hard metal metal metal This module is a property of Technological University of the Philippines Visayas and intended for EDUCATIONAL PURPOSES ONLY and is NOT FOR SALE NOR FOR REPRODUCTION.  8 Chipping: It is the process of removing considerable amount of the metal on the workpiece by driving the cold chisel in an inclined position and allowing it to move parallel to the surface. The workpiece should be clamped rigidly in the vise to counteract the forces applied on the head. Shearing: Shearing is the process of cutting a piece of steel place across its thickness in the vise. Shearing action is done when the width of the cutting edge cuts the full thickness of the workpiece diagonally. The cutting edge and the opposite jaw facing the worker serves as guide to cut in straight line. The Cold Chisel: The cold chisel is a wedge-shaped cutting tool used in cutting metal. It is provided with a shank for gripping, the head for driving with a hammer and the cutting edge for cutting. Types of Cold Chisel: 1. Straight Cutting Edge is used for trimming, edge chamfering, shearing, chipping and dividing. 2. Round Cutting Edge is used for dividing and cutting irregular shape. 3. Cape Chisel is used for grooving and keyway cutting. MATERIALS USED IN MAKING COLD CHISEL: Cold chisel should possess toughness to resist impact and hardness to cut other metals. Considering these physical properties, a high carbon steel with 0.6 to 1 percent carbon and some percentage of manganese, silicon, chromium and vanadium is a good material for cold chisel. Steps in the manufacture of cold chisel: 1. Blanking- cutting to length. 2. Forging- heating to forging temperature (2000 to 2500°F) and forming the cutting edge. 3. Stress Relieving- after forming it is heated again to about 1425°F to remove stresses developed during forging. 4. Hardening- heating the workpiece above it critical temperature and quenching it in oil or water (heating temperature 1675°F) 5. Tempering- reheating to remove brittleness and sacrificing a bit of hardness (tempering temperature 350 to 950°F) 6. Sharpening- grinding to proper lip angle. Care and Maintenance: Cold chisel should not be used to cut hardened materials or against hardened surfaces. Blunt cutting edges does not give efficient performance but rather damage the workpiece and becomes a hazard to other worker because of the tendency to fly- off it too much force is applied. As much as possible cutting edge should be sharpened to proper lip angle. Keep it free from rust and preventing the head from development of burrs or mushrooms. This module is a property of Technological University of the Philippines Visayas and intended for EDUCATIONAL PURPOSES ONLY and is NOT FOR SALE NOR FOR REPRODUCTION.  9 Safety: 1. Burrs or mushrooms should be removed by grinding. 2. The hammer being used to drive the cold chisel must have a firmly seated handle. 3. In hammering, the hammer must hit the head of the cold chisel along its axis. 4. Place guard or protective covering around your work to prevent chips from flying. PARTS OF CHISEL This module is a property of Technological University of the Philippines Visayas and intended for EDUCATIONAL PURPOSES ONLY and is NOT FOR SALE NOR FOR REPRODUCTION.  10 III. PROGRESS CHECK Multiple Choice 1. Metal cutting -----------are used with steel-headed hammers for chipping or cutting material A) Hacksaw B) Chisels C) Punch D) File 2. Chisels made for general metal work are known as _____ chisels. A. Flat B. Cold C. Hot D. Ground 3. Which chisel shape is used when removing damaged rivets? A. Diamond B. Round nose C. Flat D. Cape 4. Which chisel shape is used when creating sharp corners? A. Diamond B. Round nose C. Flat D. Cape 5. Which chisel shape is used when cutting keyways? A. Diamond B. Round nose C. Flat D. Cape 6. Which chisel shape is used when cutting concave grooves? A. Diamond B. Round nose C. Flat D. Cape1. 7. What determines the size of a chisel? A. pitch B. width C. weight D. length E. height 8. In chiseling the utilization of the applied force depends on the size of the ________. A) Lip angle B) Head C) Ferrule D) none of these 9. Straight Cutting Edge chisel is used for except A)grooving B)trimming C)shearing D) chipping 10. In manufacturing of chisel, ______ is heating to temperature of (2000 to 2500°F) and forming the cutting edge. A) Hardening B) Forging C) Tempering D) Quenching IV. REFERENCES Canadian Center for Occupational Health and Safety(2020). Hand Tools -Wrenches https://www.ccohs.ca/oshanswers/safety_haz/hand_tools Dixon,R. (1981). BenchWork: Delmar Laknepally, V., Narsampet, M. (2020). Engineering Workshop Laboratory Manual Department Of Mechanical Engineering. Retrieved From: Engineering-Workshop-i-Lab- Manual_1st%20year.pdf This module is a property of Technological University of the Philippines Visayas and intended for EDUCATIONAL PURPOSES ONLY and is NOT FOR SALE NOR FOR REPRODUCTION.  11 DeGarmo, E.P., Black, J.T., & Kosher, R.A. (1988). Materials & Processes in Manufacturing 7th Edition, Macmillan Publishing Company, New LEARNING GUIDE Week No.: __8__ TOPIC: WRENCHES (REMOVING TOOLS) I. EXPECTED COMPETENCIES Upon completing this Learning Module, the student will be able to: 1. To identify the common types of wrenches. 2. To be able to practice safety in using removing /turning tools. 3. To be able to discern to avoid doing using removing /turning tools. II. CONTENT/TECHNICAL INFORMATION Introduction: As basic of a tool as a wrench may seem, there are many types that are meant to be used for specific projects. A wrench applies torque to turn objects by either loosening or fastening items, like nuts and bolts. This hand tool is built to provide grip for turning, but with the different designs of fasteners, success can depend on having the right wrench type. Wrenches are made in various shapes and sizes and are used for gripping, fastening, turning, tightening and loosening things like pipes, pipe fittings, nuts and bolts. There are basically two major kinds of wrenches:  Pipe wrenches used in plumbing for gripping round (cylindrical) things.  General use wrenches used on nuts and bolts that have flat, parallel surfaces; e.g., square or hexagonal (hex). Wrenches may be adjustable to fit different sized pipes, nuts and bolts or may be a fixed size. Examples of adjustable wrenches Adjustable wrenches include:  Pipe wrenches.(Fig. 8.1) This module is a property of Technological University of the Philippines Visayas and intended for EDUCATIONAL PURPOSES ONLY and is NOT FOR SALE NOR FOR REPRODUCTION.  12 Fig. 8.1  Crescent (TM) wrenches which have adjustable jaws set at a 30-degree angle from the handle. Although Crescent is a trade name, it is widely used to refer to any regular adjustable wrench with an angled jaw regardless of who manufactured it. (Fig. 8.2) Fig. 8.2  Monkey wrenches which have their adjustable head at a 90-degree angle from the handle. (Fig. 8.3) Fig. 8.3 Examples of fixed-size wrenches Fixed-sized wrenches include:  Open ended wrenches that have "jaws" with parallel sides or tines that fit snugly on nuts and bolts. (Fig. 8.4) Fig. 8.4  Closed end or box wrenches that have a loop at the end with notches on the inside that allow the wrench to fit either square or hex nuts or both (depending on the number of notches or points). (Fig. 8.5) Fig. 8.5  Combination wrenches that have both an open end and a closed end on either end of the wrench; usually they fit the same size nut or bolt.(Fig. 8.6) This module is a property of Technological University of the Philippines Visayas and intended for EDUCATIONAL PURPOSES ONLY and is NOT FOR SALE NOR FOR REPRODUCTION.  13 Fig. 8.6  Socket wrenches (Fig. 8.7) are similar to closed end wrenches except they are cylindrical in shape. They can fit over a nut in a recessed hole that would be inaccessible with open or closed ended wrenches. These wrenches have an offset handle at right angles to the nut being tightened or loosened. Usually the handle is a ratchet-type handle that allows the user to turn the socket continuously in one direction by moving the handle back and forth without having to take the socket off the nut. Fig. 8.7  Torque wrenches (Fig. 8.8), one type of socket wrenches, have a built-in spring- loaded indicator that shows how much torque being is being applied (i.e., shows how hard the nut is being tightened). Fig. 8.8  Nut drivers (Fig. 8.9), another type of socket wrenches, are sockets that can be snapped on or permanently fixed to a screwdriver-type handle. Fig. 8.9  Allen wrenches or Allen keys (Fig. 8.10) are hexagon-shaped (six-sided) metal shafts that are bent into an L-shape for leverage. Hex drivers are "straight Allen wrenches" that have a screwdriver-type handle. These are different from the other wrenches since they fit inside a recessed hexagonal hole in screw heads instead of around a nut or bolt. This module is a property of Technological University of the Philippines Visayas and intended for EDUCATIONAL PURPOSES ONLY and is NOT FOR SALE NOR FOR REPRODUCTION.  14 Fig. 8.10 Fixed wrenches fit single, specific sizes. Metric wrench sizes are expressed as whole numbers (e.g., 8, 10, 14, 32) that correspond to the sizes in millimetres. Non-metric sizes used widely in the U.S. are also called S.A.E (Society of Automotive Engineers) sizes and are expressed as fractions of an inch; e.g., 1/4, 1/2, 3/4, 1 1/4. Since both metric and S.A.E. fasteners (nuts, bolts, etc.) are used in Canada, users must select the correct type and size of wrench to prevent injuries and damage to equipment in case of slippage when force is applied to the wrench. Customary tool sizes are given in fractions of an inch. The measurement is the width of the jaw opening. As shown here, these sizes are not the same as bolt sizes. (Fig 8. 11) Fig 8. 11 Metric wrench sizes are given in millimeters. The measurement is the wide of the jaw opening. The wrench size is not the same as the bolt size. (Fig 8.12) This module is a property of Technological University of the Philippines Visayas and intended for EDUCATIONAL PURPOSES ONLY and is NOT FOR SALE NOR FOR REPRODUCTION.  15 Fig 8.12  Pliers, regardless of the type, are used to grip, turn, twist and pull. The many types range from generic, square-nosed pliers to incredibly specialized designs meant for only one type of application Fig. 8.13 Linesman’s Pliers Fig. 8.14 Needle nose Pliers  Vise-Grip (Fig.8.15) is the trade name for a specific type of locking, adjustable plier known as ‘wrench pliers’. It has since come to be used when referring to any tool of this type Fig.8.15 Locking Pliers This module is a property of Technological University of the Philippines Visayas and intended for EDUCATIONAL PURPOSES ONLY and is NOT FOR SALE NOR FOR REPRODUCTION.  16 There are two types of slip joint pliers. One which has only two points of adjustment Fig. 8.16 Slip joint plier The other type are sometimes referred to as ‘Water-pump pliers (Fig. 8.17). They most commonly go under the name Channel-Locks due to that being a well known and successful brand (Fig. 8.17). Water-pump pliers Dangers of using wrenches Dangers may vary depending on the work and can include:  The wrench slips off of the work,  The work piece may suddenly break free causing you to lose balance,  The wrench or work piece may break, or  Turning the handle quickly or with pressure may create stress and strains on the hand or arm. General safety tips when using wrenches  Use the correct wrench for the job - pipe wrenches for pipes plumbing fittings, and general use wrenches for nuts and bolts.  Discard any damaged wrenches (e.g., open-ended wrenches with spread jaws or box wrenched with broken or damaged points).  Select the correct jaw size to avoid slippage.  Wear safety glasses or a face shield (with safety glasses or goggles) where there is a hazard of flying particles or falling debris.  Position your body in a way that will prevent you from losing balance and hurting yourself if the wrench slips or something (e.g., a bolt) suddenly breaks.  Use a box or socket wrench with a straight handle, rather than an offset handle, when possible.  Ensure that the jaw of an open ended wrench is in full contact (fully seated, "flat", not tilted) with the nut or bolt before applying pressure.  When turning with an adjustable wrench, the direction of the turn should be against (towards) the permanent jaw. This module is a property of Technological University of the Philippines Visayas and intended for EDUCATIONAL PURPOSES ONLY and is NOT FOR SALE NOR FOR REPRODUCTION.  17  Ensure that the teeth of a pipe wrench are sharp and free of oil and debris and that the pipe or fitting is clean to prevent unexpected slippage and possible injuries.  Apply a small amount of pressure to a ratchet wrench initially to ensure that the ratchet wheel (or gear) is engaged with the pawl (a catch fitting in the gear) for the direction you are applying pressure.  Support the head of the ratchet wrench when socket extensions are used.  Pull on a wrench using a slow, steady pull; do not use fast, jerky movements.  Stand aside when work is done with wrenches overhead.  Make sure adjustable wrenches do not "slide" open during use.  Keep tools well maintained (cleaned and oiled).  Clean and place tools and wrenches in a tool box, rack or tool belt after use. The following are to avoid when using wrenches  Do not use push on a wrench - losing your balance is more likely if the wrench slips.  Do not use a wrench that is bent handle or damaged.  Do not use worn adjustable wrenches. Inspect the knurl, jaw, and pin for wear.  Do not pull on an adjustable wrench that is loosely adjusted.  Do not use pipe wrenches on nuts or bolts.  Do not use pipe wrenches for lifting or bending pipes.  Do not use a wrench on moving machinery.  Do not use the wrong tools for the job. Never use pliers instead of a wrench or a wrench as a hammer.  Do not use a make-shift wrench.  Do not insert a shim in a wrench for a better fit.  Do not strike a wrench (except a "strike face" wrench) with a hammer, or similar object, to gain more force.  Do not increase the leverage by adding sleeved additions (e.g., a pipe) to increase tool handle length.  Do not expose a wrench to excessive heat (like from a blow torch) that could affect the temper of the metal and ruin the tool. This module is a property of Technological University of the Philippines Visayas and intended for EDUCATIONAL PURPOSES ONLY and is NOT FOR SALE NOR FOR REPRODUCTION.  18 III. Progress check Multiple choice. Support your answer in one or more sentences 1. Pliers be used for tightening and loosening small nuts. A. True B. False 2. Should you normally pull on a wrench. A. True B. False 3. Adjustable wrenches can be used exactly like open ones, by flipping them over for a new swing. A. True B. False 4. Open-end wrenches may be used to free a frozen nut A. True B. False 5. What pliers are used to reach into recessed areas? A. long-nose pliers B. side-cutting pliers c. slip-joint pliers D.vise-grip pliers 6. Which is the appropriate wrench to use when it is an easy application over the fastener in a tight situation? A. Box B. Adjustable C. Pipe D. Open 7. Which is the appropriate wrench that fits most fasteners? A. Box B. Adjustable C. Pipe D. Open 8. Which is the appropriate wrench for turning round objects? A. Box B. Adjustable C. Pipe D. Open 9. Which is the appropriate wrench to use that will surround the fastener to provide greater torque? A. Box B. Adjustable C. Pipe D. Open 10. What is another name for a hex wrench? A. nut driver B. Allen wrench C. Stillson wrench D. double-end box wrench E. ratchet and socket wrench 11. Which type of pliers open wider than any of the others? A. lineman's pliers B. long-nose pliers C. slip-joint pliers D. channel-type pliers E. diagonal-cutting pliers IV. REFERENCES Canadian Center for Occupational Health and Safety(2020). Hand Tools -Wrenches https://www.ccohs.ca/oshanswers/safety_haz/hand_tools Dixon,R. (1981). BenchWork: Delmar Laknepally, V., Narsampet, M. (2020). Engineering Workshop Laboratory Manual Department Of Mechanical Engineering. Retrieved From: Engineering-Workshop-i-Lab- Manual_1st%20year.pdf This module is a property of Technological University of the Philippines Visayas and intended for EDUCATIONAL PURPOSES ONLY and is NOT FOR SALE NOR FOR REPRODUCTION.  19 DeGarmo, E.P., Black, J.T., & Kosher, R.A. (1988). Materials & Processes in Manufacturing 7th Edition, Macmillan Publishing Company, New Y ABOUT THE AUTHOR/S This module is a property of Technological University of the Philippines Visayas and intended for EDUCATIONAL PURPOSES ONLY and is NOT FOR SALE NOR FOR REPRODUCTION.