chapter 4 power tools and equipment answers manufacturer

tools driven by compressed air, electricity, or pressurized liquid Shop equipment large shop tools such as floor jacks, parts cleaning tanks, and steam cleaners

Connected to the metal lines from the air compressor Allow the technician to take a source of air pressure to the vehicle being repaired Quick-disconnect connectors allow a technician to connect or disconnect hoses or tools without using a wrench

used to set a specific pressure in the system ( psi, or kPa) Filter traps water so that it can be drained daily Lubricator introduces oil into the airstream increases the life of air tools

Must be used with air wrenches Case hardened, thicker, and much stronger than conventional sockets and extensions Impact tools are flat black, instead of chrome Using a chrome tool on an impact wrench can be unsafe

After studying this chapter, you will be able to: Air Compressor List the most commonly used power tools and An air compressor is the source of compressed air equipment. for an automotive service facility. Look at Figure 4-1. An Describe the uses for power tools and equipment. air compressor normally has an electric motor that spins Explain the advantages of one type of tool over an air pump. The air pump forces air into a large, metal another. storage tank. The air compressor turns on and off auto- Explain safety rules that pertain to power tools matically to maintain a preset pressure in the system. Metal air lines feed out from the tank to several locations and equipment. in the shop. Technicians can then connect their flexible Correctly answer ASE certification test questions air hoses to the metal lines. that require a knowledge of power tools and equipment. Warning! Shop air pressure usually ranges from 100- 150 psi (689-1034 kPa). This is enough pres- To be a productive technician in today"s automotive sure to kill or severely injure a person. Respectservice facility, you must know when and how to use shop air pressure!power tools and equipment. Power tools are tools drivenby compressed air, electricity, or pressurized liquid. They Air Hosesmake many repair operations easier and quicker. Largeshop tools, such as floor jacks, parts cleaning tanks, and Flexible, high-pressure air hoses are connected to thesteam cleaners, are called shop equipment. metal lines from the air compressor. These hoses allow This chapter discusses properly selecting and using the technician to take a source of air pressure to thecommon power tools and shop equipment. They can be vehicle being repaired. Quick-disconnect couplings arevery dangerous if misused. Always follow the operating used to connect air hoses and air tools to the compressedinstructions for the particular tool or piece of equipment air system without using a wrench. To join or separate abefore use. If in doubt, ask your instructor for a demon-" quick-disconnect coupling, pull back on the coupling"sstration. Specialized power tools and equipment are cov- outer sleeve with finger pressure. With the sleeve pulledered in later chapters. Refer to the index to find more back, you can push the coupling together or pull it apart.information 011 them as needed.

Other ComponentsCompressed-Air System A pressure regulator is used to set a specific pres- The components of a compressed-air system include sure in the compressed-air system. This pressure is oftenan air compressor, air lines, air hoses, and air tools. In called shop pressure. In most cases, shop pressure isaddition, a pressure regulator, filter, and lubricator may between 100 and 150 pounds per square inch (psi). Abe attached to the system. Air tools are driven by the filter may be connected to the system. The filter removescompressed-air system. Air-powered tools can be found water from the compressed air. This increases the life ofin nearly every service facility. air tools. In addition, a lubricator may also be connected

Air Tools Air tools use the energy of compressed air for opera-tion. They are also called pneumatic tools. Air tools arelabor-saving devices and well worth" their cost. Alwayslubricate an air tool before and after use. While pressingthe air tool"s trigger, squirt a few drops of air tool oil intothe tool"s air inlet fitting. Not only will the oil protect theinternal parts of the tool during use, but it will also pre-vent the internal parts from rusting during storage. A

Air Wrenches Air wrenches, or impact wrenches, provide a veryfast means of installing or removing threaded fasteners.Look at Figure 4-2A. An impact wrench uses com~pressed air to rotate a driving head. The driving headholds a special impact socket. B Impact wrenches come in 3/8//, 1/2"/, and 3/4/1 drivesizes. A 3/8/1 drive impact is ideal for small fasteners, Figure 4-2. A-1/2" drive impact wrench. B-3/8" drive airsuch as 1/4//-9/16/1 bolts. A 1/2/1 drive is for general pur- ratchet. (Snap-on Tool Corp.)pose use with medium to large fasteners, such as 1/2//- r/bolts. The 3/4// drive impact is for extremely large fas-teners. It is not commonly used in automotive service. A Caution!button or switch on the impact wrench controls the direc- Until you become familiar with the operation oftion of rotation. In one position, the impact wrench an air wrench, be careful not to overtightentightens the fastener. With the switch in the other posi- bolts and nuts or leave them too loose. It is easytion, the wrench loosens the fastener. to strip or break fasteners with an air tool. Chapter 4 Power Tools and Equipment 49

Air Ratchet hammering attachments are available. Be sure to select the correct one for the job. An air ratchet is a special impact wrench designedfor working in limited space. Look at Figure 4-2B. For Warning! Never turn an air hammer on unless the toolinstance, an air ratchet is commonly used when removingwater pumps. It will fit between the radiator and engine head is pressed tightly against the workpiece.easily. It works in much the same way as a hand-tool Otherwise, the tool head can fly out of theratchet. An air ratchet normally has a 3/811 drive. hammer with great force, as if shot from a gun!However, it does not have very much turning power.Final tightening and initial loosening must be done with Blowgunhand tools. An air-powered blowgun is commonly used to dry and clean parts washed in solvent. It is also used to blowImpact Sockets and Extensions dust and loose dirt from parts before or during dis- Special impact sockets and impact extensions must assembly. See Figure 4-4A.be used with air wrenches. These are case hardened, When using a blowgun, wear eye protection. Directthicker, and much stronger than conventional sockets and the blast of air away from yourself and others. Do notextensions. A conventional socket can be ruined or blow brake and clutch pmts clean. The dust from thesebroken by the hammering blows of an impact wrench. parts may contain asbestos. Asbestos is a cancer-causingImpact sockets and extensions are easily identified substance. Another type of blowgun is a solvent gun,because they are flat black, not chrome. Figure 4-4B. It can be used to wash parts that will not fit into a cleaning tank.A.~ Caution! Know when and when not to use power tools. In most situations, power tools will speed up your wo~k. However, there are many times when they should not be used. For example, never use an impact wrench in place of a torque wrench. An impact wrench will not torque crit- ical fasteners to their correct specification. Problems and comebacks will result.

Air Drill An air drill is excellent for many repairs because ofits power output and speed adjustment capabilities. Itspower and rotating speed can be set to match the job athand. Look at Figure 4-5. With the right attachments, airdrills can drill holes, grind, polish, and clean parts. A rotary brush is used in an air or electric drill forrapid cleaning of parts, Figure 4-6. It can quickly removeold gasket material, carbon deposits, and rust with a min-imum amount of effort. An abrasive pad is another type of cleaning tool thatcan be used in an air or electric drill. It is used for Figure 4-7. This die grinder is equipped with a high-speedremoving old gasket material. It has the advantage of not stone. This tool is used for removing burrs and for otherscratching aluminum like a rotary brush can. smoothing operations. Here, the technician is making minor repairs to a damaged cylinder head combustion chamber. A rotary file, or stone, can be used in an air drill,electric drill, or air (die) grinder, Figure 4-7. It is handyfor removing metal burrs and nicks. Make sure the stoneis not turned too fast by the air tool. Normally, the max- Electric Toolsimum speed is printed on the file or stone container. There are many electric tools that can be useful to a Warning! technician. Some of these tools, such as a drill press or Use a high-speed rotary brush in an air drill. A grinder, may be fixed to the floor or a bench. Other tools, brush designed for an electric drill may fly such as a drill, are portable and can be taken to the job site. apart. To be safe, always adjust an air drill to the slowest acceptable speed when using a - Bench Grinder rotary brush. Also, always wear eye protection. A bench grinder can be used for grinding, cleaning, or polishing operations, Figure 4·8. A bench grinder usually has two wheels-a grinding wheel and a wire wheel. The hard, abrasive grinding wheel is used for sharpening and deburring. The soft wire wheel is used for cleaning and polishing. A few bench grinder rules to follow are: • Always wear eye protection and keep your hands away from the wheel. • Make sure the grinder shields are in place.

Drills Drills are used to create holes in metal and plasticFigure 4·6. A rotary brush is commonly used in a drill for parts. Some drills are portable; others are mounted on acleaning off carbon deposits or old gaskets. Always wear eye workbench or the floor. Drills use different-size bits toprotection. create the size of hole needed. Chapter 4 Power Tools and Equipment 51

Figure 4-10. A key is used to tighten a bit in the chuck.Figure 4-8. The grinding wheelan a bench grinder is used tosharpen tools. The wire wheel can be used to clean and polishsmall parts. Always keep shields, tool rests, and guards in place.

Transmission JackHydraulic Tools Transmission jacks are designed to hold transmis- Hydraulic fools are powered by pressurized liquid. sions and transaxles during removal or installation. OneThe hydraulic tools typically used in the automotive shop type is similar to a floor jack. However, the saddle isinclude jacks, cranes, and presses. These tools are dis- enlarged to fit the bottom of a transmission. Another typecussed in the next sections. of transmission jack is designed to be used when the vehicle is raised on a lift, Figure 4-14. It has a long post that can reach high into the air to support the transmission.Floor Jack A floor jack is used to raise either the front, sides, orrear of a vehicle. Look at Figure 4·13. To avoid vehicledamage, place the jack saddle under a solid part of the carsuch as the frame, suspension arm, or axle housing. If the

Figure 4-14. A transmission jack is designed for holding trans- missions during removal, transporting, and installation. ThisFigure 4-13. A floor jack is for raising the car only. foot-operated, hydraulic stand can be extended to a height(Lincoln Automotive) of 72". (OTC Div. of SPX Corp.) Chapter 4 Power Tools and Equipment 53

Engine Crane , • Warning! A hydraulic press can literally exert tons of A portable engine crane is used to remove and install force. Wear eye protection and use recom-heavy engine assemblies, Figure 4-15. It has a hydraulic mended procedures. Parts can break and fly outhand jack for raising engines and a pressure-release valve with deadly force!for lowering engines. The engine crane is also handy forlifting intake manifolds, cylinder heads, engine blocks,transmissions, transaxles, and other heavy parts. Shop Equipment In addition to pneumatic, hydraulic, and electricHydraulic Press tools, there are various pieces of shop equipment that a technician may find useful. These include tire changers, A hydraulic press is used to install or remove gears, stands, cleaners, welders, lights, and creepers. These arepulleys, bearings, seals, and other parts requiring a high all discussed in the following sections.pushing force. One is shown in Figure 4-16. A hydraulicram extends as the pump handle is worked. The rampresses the parts against a table. Arbor Press An arbor press works like a hydraulic press. However, it is all mechanical. Hydraulic pressure is not used; therefore, the operating pressure is much lower. An arbor press is suited for smaller jobs.

Oxyacetylene Torch An oxyacetylene torch can be used to heat, cut, weld, or braze metal parts, Figure 4-20. The oxy- acetylene setup consists of an oxygen tank, an acetylene tank, pressure regulators, hoses, and a hand-held torch. Tremendous heat is produced by the burning acetylene gas and oxygen. The oxyacetylene cutting torch is often used to remove old, rusted exhaust systems. To use an oxyacetylene cutting torch: 1. Put on all necessary protective gear, including a welding helmet or goggles, welding gloves, and a leather jacket. 2. Inspect the oxyacetylene equipment forFigure 4-18. A cold-solvent tank is used to remove oil and lightgrease from parts. The unit sprays filtered solvent onto parts. damage and make sure all cylinder, regu-Rub the parts with a brush for rapid cleaning. lator, and torch valves are closed. 3. Light the cutting torch according to the manufacturer"s recommendations. 4. With the torch held at a 90° angle to theSteam Cleaner and High-Pressure Washer workpiece, concentrate the flame on the A steam cleaner or high-pressure washer is used to spot where the cut will begin.remove heavy deposits of dirt, grease, and oil from the S. When the spot becomes cherry red, depressoutside of large assemblies, such as engines, transmis- the oxygen cutting lever to begin the cut.sions, and transaxles. Look at Figure 4-19. To help keep 6. Move the torch along the workpiece tothe environment clean, wire brush the item to be cleaned make the cut.and collect oil-soaked dirt before steaming or washing. 7. After making the cut, release the cuttingThen, dispose of the oil-soaked material properly. lever and shut off the torch. Chapter 4 Power Tools and Equipment 55

Pressure regulator Soldering Gun valve Acetylene Oxygen A soldering gun or soldering iron is used to join Hoses wires during electrical repairs, Figure 4-21. An electric current heats the tip of the gun. The hot gun tip is used to heat the wires. Solder is then applied to the hot wires and Tanks it melts. Solder is a lead-tin alloy. When the solder cools, it hardens into a strong, solid connection.A Battery Charger 240 volt electrical A battery charger is used to re-energize a "dead," or outlet discharged, battery. It forces current back into the battery to recharge the plates and battery acid. The red charger lead connects to the positive (+) battery terminal. The black charger lead connects to the negative (-) battery Power switch terminal.

Figure 4-20. A-An oxyacetylene outfit can be used for cuttingor welding metal. B-A basic arc welder. (Sun) ~-)--~~)~ A \ Tip Power cord /

Figure 4-22. A-Droplight. B-Drop or extension cord.C- Three-prong adapter with ground terminal and ground wirefor safety. D-Fluorescent droplight. (Florida Dept. of Voc. Ed.) Figure 4-24. Jumper cables are used for emergency starting. Chapter 4 Power Tools and Equipment 57

Creepers Covers A creeper is useful when working under a car sup- Fender covers are placed over fenders, upper grille,ported on jack stands, Figure 4-25A. It lets the techni- or other body sections to prevent vehicle damage. Theycian easily roll under vehicles without getting dirty. A protect the paint or finish from nicks, scratches, andstool creeper allows the technician to sit while working grease. See Figure 4-27. Never lay tools on a painted sur-on parts that are near the ground. See Figure 4-25B. For face. Costly scratches may result.example, a stool creeper is often used during brake Seat covers are placed over seats to protect themsystem repairs. The brake parts and tools can be placed from dirt, oil, and grease that might be on your workon the creeper. The service technician can sit and still be clothes. These covers should be used while driving theat eye level with the brake assembly. vehicle or while working in the passenger compartment.

Roll-Around Cart Workplace Skills A large roll-around cart or table is handy for taking a Social skills are the techniques you use to conductnumber of tools to the job. One is pictured in Figure 4-26. yourself in such a way that your customers and fellowA technician can quickly place all needed tools in the cart employees like and respect you. Many times, you willand take them to the vehicle. The cart places the tools need the help of another technician to complete a dif-within hand"s reach: This saves time and effort before, ficult task. If your co-workers dislike you, you may haveduring, and after the job. trouble finding help when you need it

Summary • Power tools use electricity, compressed air, or hydraulic pressure (liquid confined under pres- sure). Large shop tools, such as floor jacks, parts cleaning tanks, and steam cleaners, are classified as shop equipment. • An air compressor is the source of compressed (pressurized) air for the auto shop.A B • High-pressure air hoses are connected to the metal lines from the air compressor.Figure 4-25. A-A creeper is for working under a vehicle.S- The stool creeper is commonly used during brake and sus- • Air tools, also called pneumatic tools, use airpension repairs. You can sit on the stool and store tools on the pressure for operation. They are labor-savingbottom. (Snap-on Tool Corp.) tools and are well worth their cost.

Figure 4-26. A roll-around cart allows you to take many tools tothe vehicle. This saves several trips to the toolbox. It also saves Figure 4-27. Always take good care of your customer"s vehicle.time during cleanup at the end of the day. (Snap-on Tool Corp.) Fender covers protect the paint from nicks and dents.58 Section 1 Introduction to Automotive Technology

• Air wrenches, or impact wrenches, provide a very fast means of installing or removing threaded Important Terms fasteners. Power tools Portable electric drills • Special impact sockets and impact extensions Shop equipment Drill press must be used with air wrenches. Air compressor Hydraulic tools Air hoses Floor jack • A blowgun is commonly used to dry and clean Quick -disconnect Transmission jacks parts washed in solvent. connectors Engine crane • An air drill is excellent for many repairs because Pressure regulator Hydraulic press of its power output and speed adjustment Filter Arbor press capabilities. Lubricator Tire changer • A bench grinder can be used for grinding, Air tools Jack stands cleaning, or polishing operations. The hard Air wrenches Engine stand grinding wheel is used for sharpening or debur- Impact wrenches Cold solvent tank ring. The soft wire wheel is for cleaning and Air ratchet Steam cleaner polishing. Impact sockets High-pressure washer • Drill bits, or twist drills, are used to drill holes in Impact extensions Oxyacetylene torch Air hammer Welder metal and plastic parts. Air chisel Soldering gun • A drill bit is mounted in and rotated by a drill. A Blowgun Soldering iron special key is sometimes needed to tighten the drill bit in the drill chuck. . Solvent gun Battery charger Air drill Droplight • A floor jack is used to raise either the front, sides, Rotary brush Pullers or rear of a vehicle. Abrasive pad Jumper cables • A tire changer is a common piece of shop equip- Rotary file Creeper ment used to remove and replace tires on wheels. Stone Stool creeper • Jack stands support a vehicle during repair. After Electric tools Roll-around cart raising a vehicle with a jack, place stands under Bench grinder Fender covers the vehicle. Drill bits Seat covers

• A portable engine crane is used to remove and install engines. Review Questions-Chapter 4 • An engine stand is used to hold an engine while it Please do not write in this text. Place your answers is overhauled (rebuilt) or repaired. on a separate sheet of paper. • A cold solvent tank can be used to remove grease 1. Power tools use __ , , or __ and oil from parts. __ as sources of energy. • An oxyacetylene torch outfit can be used to heat, 2. Which of the following is not a commonly used cut, weld, or braze metal parts. air tool? • A welder is used to melt and fuse metal parts (A) Impact wrench. together. (B) Air ratchet. • A soldering gun or iron is used to solder wires. (C) Air chisel. (D) Air saw. • A battery charger is used to recharge a discharged car battery. 3. A(n) __ is used to blow dirt off parts and to dry parts after cleaning. • A drop light provides a portable source of light. 4. A rotary file is frequently used to remove __ . • Pullers are needed to remove seals, gears, pulleys, (A) old gasket materials steering wheels, axles, and other pressed-on parts. (B) carbon deposits • Jumper cables are used to start engines that have (C) metal burrs and nicks a dead (discharged) battery. (D) None of the above. • Fender covers are placed over the fenders, the 5. List four important rules for a bench grinder. upper grille, or other body sections to protect them. 6. List five important rules for a drill press. Chapter 4 Power Tools and Equipment 59

7. are used to support a vehicle while 6. Each of the following can be used to clean working under it. parts except: (A) Floor jacks (A) air drill. (B) Jack stands (B) blowgun. (C) Transmission jacks (C) air ratchet. (D) Bumper jacks (D) bench grinder. 8. Explain the use of a solvent tank. 7. Which of the following is not a rule to follow9. What are wheel pullers for? when using a bench grinder?10. A 1/2" drive impact wrench is used for fasteners (A) Wear eye protection. with head sizes between 1/2" to 1". Which of the (B) Make sure shields are in place. following sockets can be used by this particular (C) Use the wire wheel to clean soft metal tool? parts. (A) 5/8" chrome plated socket. (D) Keep the tool rest adjusted close to the (B) 9/16" flat black socket. stone and brush. (C) 7/16" flat black socket. 8. When using a drill press, Technician A (D) None of the above. believes drilling pressure should not be released until the bit breaks completely through the bottom of the part. Technician B ASE- Type Questions believes pressure release should occur just before the bit breaks through. Who is right? 1. Power tools are tools that use: (A) A only. (A) electricity. (B) B only. (B) hydraulics. (C) Both A and B. (C) compressed air. (D) Neither A nor B. (D) All of the above. 9. After using a floor jack to raise the front of a 2. Technician A says that shop air pressure is usu- car: ally around 100 to 150 psi. Technician B says (A) place the car in park. shop air pressure is much higher, around (B) block the car"s wheels. 300 psi. Who is correct? (C) secure the car on jack stands. (A) A only. (D) All of the above. (B) B only. 10. The __ press performs the same function as (C) Both A and B. a hydraulic press, but at lower pressures. (D) Neither A nor B. (A) arbor 3. Which of the following IS not a common (B) steam impact wrench drive size? (C) rotary (A) 1/4". (D) ratchet (B) 3/8". (C) 1/2". (D) 3/4". Activities for Chapter 44. Technician A says to use a 1/4" drive on sockets from 1/4" to 9/16". Technician B says to use a 1. Using an automotive tool catalog, develop a list 3/8" drive on these socket sizes. Who is correct? of power tools needed to equip your school"s (A) A only. automotive repair shop. Find prices and add up (B) B only. the cost. (C) Both A and B. 2. Research safety literature on power equipment (D) Neither A nor B. used in an automotive repair facility. 5. Special impact sockets and extensions are (A) Develop a bibliography of resources for easily identified because they are: safe use of power equipment. (A) chrome. (B) Develop a list of safety rules for their use. (B) aluminum. (C) flat black. (D) hard rubber.

Industrial robot control systems, or robot controllers, consist of several parts, including a power source, sensors, input signals from the sensors to a computer or microprocessor (wired or wireless), programming functions, and output command signals back from the computer or microprocessor to the manipulator and/or end-effectors (wired or wireless).

Energy is provided to various robot sensors, actuators, and their controllers as electrical, pneumatic, or hydraulic power. These power sources can be hazardous to workers depending on the energy infeed(s) and/or the resulting energy produced (e.g. motion, stored energy). Hazardous energy can exist in internal components such as capacitors, springs, pressurized cylinders, and other energy sources. See the Hazards Associated with Industrial Robot Applications section of this chapter for more about these hazards.

The robot"s drives are usually electrically powered. Selection of the robot system is usually based upon application requirements. For example, pneumatic power (typically 80-90 psi air) is often used for end-effectors, and hydraulic power can be used for associated processes. Consideration should be given to potential hazards of fires from leaks if flammable materials are used as the hydraulic fluid.

Electrically-powered robots are by far the most prevalent in industry. Either AC or DC electrical power can be used to supply energy to electromechanical drives, sensors, and the robot"s respective control systems. Electrical motion control is superior compared to pneumatic and hydraulic. In an emergency, an electrically-powered robot can be stopped or powered down more safely and faster than those powered pneumatically or hydraulically.

End-effectors are sometimes referred to as End-of-Arm Tooling (EOAT). Many industrial robot systems use robots that can be equipped with different end-effectors as required for the application. Common end-effectors include grippers, pickers, welding torches, cutting and trimming tools, material removal tools, drilling tools, collision sensors, force-torque sensors, inspection equipment, cameras, and adhesive dispensers.

Similar to above, the breakdown of the end-effector, workpiece, peripheral equipment, or its power source is a mechanical failure. Parts release, gripper mechanism failure, or end-effector power tool failure (e.g., grinding wheels, buffing wheels, deburring tools, power screwdrivers, and nut runners) are also sources for mechanical failure hazards and injuries.

Slipping, tripping and falling hazards and injuries are common in almost any workplace. Spills or leaks can result in slipping hazards. Equipment, power cables, and hoses can present tripping and falling hazards. General housekeeping is an element that should be maintained in all workplaces.

The operational characteristics of robot applications can be significantly different from other machines and equipment. Robots are capable of high-energy (fast and/or powerful) movements through a large volume of space beyond the base dimensions of the robot (see Figure IV-3). However, even low-energy robots that look harmless (i.e., robots with payloads as low as 6-1/2 pounds or 3 kilograms) can be used in very dangerous applications.

Some workers (i.e., programmers, operators, maintenance) can be required to be within the restricted space while power is available to actuators, valves, sensors, end-effectors, or other energy sources. The restricted space of one robot application can also overlap a portion of the restricted space of other robot applications, or work zones of other industrial machines and related equipment. Thus, a worker can be hit by one robot system or workpiece while working on another, trapped between them or peripheral equipment, or hit by flying objects (projectiles) released by an end-effector or other materials.

Pneumatic, hydraulic, or electrical power sources that have malfunctioning control or transmission elements in the robot power system can disrupt electrical signals to the control and/or power source lines. Fire risks are increased by electrical overloads or by use of flammable hydraulic oil. Electric shock and release of stored energy from accumulating devices can also be hazardous to workers.

A fellow worker accidentally tripped the power switch while another maintenance worker was servicing an assembly robot. The manipulator struck the maintenance worker"s hand.

The application did not meet applicable electrical safety standards because turning on power is not to cause operation or movement of the robot application.

Power and other hazardous energy sources should be controlled in accordance with 29 CFR 1910.147, The Control of Hazardous Energy (Lockout/Tagout),or 29 CFR 1910.333, Selection and Use of Work Practices.

When maintenance, repairs, and/or troubleshooting must be performed with power on and with maintenance workers performing their work within the safeguarded space, the robot should be in manual mode. Additional hazards can be present during this manual mode because some of the robot application safeguards may not be active and functioning as during automatic mode. To protect maintenance and repair workers, safeguarding techniques and procedures as stated in the ANSI/RIA R15.06-2012 Part 2, Sections 5.9.7, 5.10.2, 5.12.1, 7.2.7 are recommended.

Power and other hazardous energy sources should be controlled in accordance with 29 CFR 1910.147, The Control of Hazardous Energy (Lockout/Tagout),or 29 CFR 1910.333, Selection and Use of Work Practices.

The robot system moves under a worker"s direct control while in automatic mode and executing its program. The worker controls the motion for the collaborative portion of the task (similar to powered-assist tools/machinery). With HGC, a worker can guide a robot system to grasp a heavy box. The worker may then guide the robot system to place the box onto a truck. The robot application in this case is doing all the heavy lifting, but will not move without the worker physically directing it while the worker presses (or actuates) a hold-to-run control device.

There are two ways that PFL capability can be provided. One is by inherently safe design of the robot (e.g., low energy potential due to very low payload and/or speed capability). Another is by control means, which is described as by safety functions using sensors and safety-related parts of the control system (SRP/CS) (e.g., torque sensors on all joints to safety logic that will slow or stop the robot). PFL robots that have the capability to limit energy transfer have safety functions that are configured, so contact pressures and forces do not exceed acceptable limits. The typical safety functions are speed limiting, force limiting, and power limiting. Collaborative applications using PFL robots usually operate at much lower speeds and payloads than they are physically capable. This is so that when the robot contacts a worker, not only does the robot stop quickly, but also the robot is not moving with enough energy to cause injury. [Note: robot contact with sensitive body regions (e.g., the face, temples, and throat) is to be prevented or avoided per RIA TR R15.606-2016.]

ISO 10218-2:2011, and RIA 15.06 Clause 5.11.5.5, requires that parameters of power, force, and ergonomics pertaining to power and force limited robot systems are to be determined by a risk assessment. Limits for quasi-static and transient contact must be evaluated as part of the risk assessment, and by determining pressure and force threshold limit values on the collaborative robot system utilizing Tables A.1 and A.2 in Annex A of RIA TR15.606.

With SMS, power to the actuators is retained, which enables a quicker resumption of operation and less wear on contactors and other hardware. For SMS to work, continued detection of the worker(s) is requires in the safeguarded space (e.g., usually by motion sensors). The robot application is permitted to automatically resume operation if assured that no workers are within the space without the need for the worker(s) to press a restart button. When an SMS is activated, the power to the robot system remains on, but the stop is automatically held in a monitored standstill state. While in the standstill state, any movement from within the safeguarded space will result in an immediate stop (similar to an emergency stop).

The specific tasks that are important to safely complete the job or that present hazards to the workers should be listed on the RA. For example, "collecting tools" may not need to be listed as a task on the RA.

RIA TR R15.606-2016 also provides guidance on the allowable speed to stay within the biomechanical limits during a transient contact event. See also RIA TR R15.806-2018, Testing Methods for Power & Force Limited Collaborative Applications, for specific guidance on how to measure pressure and forces. Then use this guidance to compare the pressures and other forces to the permissible biomechanical limits. The integrator should use the robot manufacturer"s information (i.e., moving mass of the manipulator, speed capabilities) combined with the payload mass of the end-effector and/or workpiece to determine the maximum allowable speed for contact events.

RIA TR R15.806-2018, Testing Methods for Power & Force Limited Collaborative Applications. Describes methods to test and verify that the pressure and other forces exerted by a collaborative robot application remain within the allowable limits described in TR R15.606-2016.

RIA TR R15.806-2018, Technical Report for Industrial Robots and Robot Systems — Safety Requirements — Testing Methods for Power & Force Limited Collaborative Applications

End-effector – An accessory device or tool specifically designed for attachment to the robot wrist or tool mounting plate to enable the robot to perform its intended task. Examples may include gripper, spot-weld gun, arc-weld gun, spray-paint gun, inspection camera, adhesive dispenser, or any other application tools.

Industrial Robot – A reprogrammable, multifunctional manipulator designed to move material, parts, tools, or specialized devices through variable programmed motions for the performance of a variety of tasks.

Numerically Controlled Machine Tools – Operated by a series of coded instructions comprised of numbers, letters of the alphabet, and other symbols. These are translated into pulses of electrical current or other output signals that activate motors and other devices to run the machine.

All portable, power-driven circular saws having a blade diameter greater than 2 in. shall be equipped with guards above and below the base plate or shoe. The upper guard shall cover the saw to the depth of the teeth, except for the minimum arc required to permit the base to be tilted for bevel cuts. The lower guard shall cover the saw to the depth of the teeth, except for the minimum arc required to allow proper retraction and contact with the work. When the tool is withdrawn from the work, the lower guard shall automatically and instantly return to covering position.

All hand-held powered circular saws having a blade diameter greater than 2 inches, electric, hydraulic or pneumatic chain saws, and percussion tools without positive accessory holding means shall be equipped with a constant pressure switch or control that will shut off the power when the pressure is released. All hand-held gasoline powered chain saws shall be equipped with a constant pressure throttle control that will shut off the power to the saw chain when the pressure is released.

All hand-held powered drills, tappers, fastener drivers, horizontal, vertical, and angle grinders with wheels greater than 2 inches in diameter, disc sanders with discs greater than 2 inches in diameter, belt sanders, reciprocating saws, saber, scroll, and jig saws with blade shanks greater than a nominal one-fourth inch, and other similarly operating powered tools shall be equipped with a constant pressure switch or control, and may have a lock-on control provided that turnoff can be accomplished by a single motion of the same finger or fingers that turn it on.

All other hand-held powered tools, such as, but not limited to, platen sanders, grinders with wheels 2 inches in diameter or less, disc sanders with discs 2 inches in diameter or less, routers, planers, laminate trimmers, nibblers, shears, saber, scroll, and jig saws with blade shanks a nominal one-fourth of an inch wide or less, may be equipped with either a positive "on-off" control, or other controls as described by paragraph (a)(2)(i) and (ii) of this section.

The operating control on hand-held power tools shall be so located as to minimize the possibility of its accidental operation, if such accidental operation would constitute a hazard to employees.

This subparagraph does not apply to concrete vibrators, concrete breakers, powered tampers, jack hammers, rock drills, garden appliances, household and kitchen appliances, personal care appliances, medical or dental equipment, or to fixed machinery.

Explosive-actuated fastening tools that are actuated by explosives or any similar means, and propel a stud, pin, fastener, or other object for the purpose of affixing it by penetration to any other object shall meet the design requirements specified by paragraph (d)(2) of this section. This requirement does not apply to devices designed for attaching objects to soft construction materials, such as wood, plaster, tar, dry wallboard, and the like, or to stud-welding equipment.

Operators and assistants using tools shall be safeguarded by means of eye protection. Head and face protection shall be used, as required by working conditions, as set forth in subpart I.

The tool shall be so designed that positive means of varying the power are available or can be made available to the operator as part of the tool, or as an auxiliary, in order to make it possible for the operator to select a power level adequate to perform the desired work without excessive force.

Tools of the low-velocity-piston type shall have the characteristics outlined in paragraphs (d)(2)(ii) (a) through (e) of this section and any additional safety features he may wish to incorporate.

The tool shall be so designed that positive means of varying the power are available or can be made available to the operator as part of the tool, or as an auxiliary, in order to make it possible for the operator to select a power level adequate to perform the desired work without excessive force.

Tools of the hammer-operated piston tools - low-velocity type shall have the characteristics outlined in paragraphs (d)(2)(iii) (a) through (e) of this section.

The tool shall be so designed that positive means of varying the power are available or can be made available to the operator as part of the tool, or as an auxiliary, in order to make it possible for the operator to select a power level adequate to perform the desired work without excessive force.

Fasteners shall not be driven directly into materials such as brick or concrete closer than 3 inches from the unsupported edge or corner, or into steel surfaces closer than one-half inch from the unsupported edge or corner, unless a special guard, fixture, or jig is used. (Exception: Low-velocity tools may drive no closer than 2 inches from an edge in concrete or one-fourth inch in steel.)

Power lawnmowers of the walk-behind, riding-rotary, and reel power lawnmowers shall be guarded in accordance with the machine guarding requirements in 29 CFR 1910.212, General requirements for all machines.

All power-driven chains, belts, and gears shall be so positioned or otherwise guarded to prevent the operator"s accidental contact therewith, during normal starting, mounting, and operation of the machine.

A rigid bar fastened across the discharge opening, secured to prevent removal without the use of tools. The bottom of the bar shall be no higher than the bottom edge of the blade enclosure.

Wheel drive disengaging controls, except deadman controls, shall move opposite to the direction of the vehicle motion in order to disengage the drive. Deadman controls shall automatically interrupt power to a drive when the operator"s actuating force is removed, and may operate in any direction to disengage the drive.

A rigid bar fastened across the discharge opening, secured to prevent removal without the use of tools. The bottom of the bar shall be no higher than the bottom edge of the blade enclosure.

Hand-operated wheel drive disengaging controls shall move opposite to the direction of vehicle motion in order to disengage the drive. Foot-operated wheel drive disengaging controls shall be depressed to disengage the drive. Deadman controls, both hand and foot operated, shall automatically interrupt power to a drive when the operator"s actuating force is removed, and may operate in any direction to disengage the drive.

Twist drills- A twist drill is a pointed cutting tool used for making cylindrical holes in the workpiece. It has helical flutes along its length for clearing chips from the holes. Twist drills are the most common used today, but there are many other styles with different purposes. A twist drill is composed of three major parts: a shank, body, and point. The shank is the part of the drill bit held in the spindle of the drill press. The drill press’ power is transferred through the shank. Shanks are either one of two styles, straight or tapered. Straight shank drills are held in a friction chuck. Slippage between the drill bit and the chuck is often a problem, especially for larger drills. When using drill bits larger than 1/2” dia., tapered shank drill bits are often used. These provide greater torque with less slippage than straight shank drill bits. The body, as described above, generally has two flutes to clear chips. These flutes are not cutting edges and should not be used for side cutting as an end mill. The point of the drill bit does all of the cutting action, which produces the cut chips. The point is ground on the end of the drill bit.

Hand and power tools are a common part of our everyday lives and are present in nearly every industry. These tools help us to easily perform tasks that otherwise would be difficult or impossible. However, these simple tools can be hazardous and have the potential for causing severe injuries when used or maintained improperly. Special attention toward hand and power tool safety is necessary in order to reduce or eliminate these hazards.

Pneumatic power tools must be secured to the hose in such a way as to prevent accidental disconnection. Safety clips or retainers must be securely installed to prevent attachments from being inadvertently expelled.

Appropriate personal protective equipment, such as safety glasses with side shields, face shields, leather work gloves, or leather work boots must be worn when using hand tools.

Portable power tools are designed for a wide variety of uses. Circular saws, jigsaws, drills, hammer-drills, sanders, grinders, routers and numerous other power tools, save time and effort on the job. The increased use of power tools heightens the need for awareness of the hazards they present if not operated properly. While each type of tool has its own unique hazards which must be taken into account, the following safety rules are common to all power tools.