Lean Manufacturing Mentor Guide For Manual Lathes And .

2y ago
106 Views
2 Downloads
3.88 MB
65 Pages
Last View : 1d ago
Last Download : 2m ago
Upload by : Wade Mabry
Transcription

Mechanical Engineering DepartmentME 410 Principles of Lean Manufacturing, 2017TitleLean Manufacturing Mentor GuideFor Manual Lathes and Manual MillsStudentsoriginal draft by Mostafa Asfoor and Drew Flerchingerupdated Feb. 6, 2014 & June 2, 2017

Lean Manufacturing Mentor GuideContentsProject Description .Shop Orientation/Safety .General Lathe Tips .Lathe Operations .Lath Project Manufacturing Plan .General Mill Tips .Lathe Operations .Mill Project Manufacturing Plan .General CNC Machining Tips .General Welding Tips .AppendixMill/ Lathe/ Drill Cutting Speeds, Feed Rate Chart

Lean Manufacturing Mentor GuideProject DescriptionThis project was proposed as a kaizen project for Lean Manufacturing. Before its completion, there was noorganized introduction to mentoring for Lean Manufacturing. This was especially problematic for students that hadnever taken the class before mentoring it. To remedy this situation, a binder has been made that outlines the stepsof the block project that the students complete over the first two weeks of the class. The purpose of this project isto provide a forum for mentors to stay one day ahead of the students for machining the block as well as offermethods and tips for conducting the machining processes to help the mentor answer questions the students mayhave and make sure everything is done correctly.In its present state, this binder includes thorough manufacturing plans for making each part on the manual milland lathe. After each machine’s manufacturing plan is a section of notes regarding correct procedure for eachprocess required to make the block from. Notes for giving shop orientation on the manual mills and lathes are alsoincluded as a quick reference for mentors.As this is a kaizen project, it is not complete, but rather should be added to in the future. In order to encouragethis, the table of contents does not include page numbers for each section, but rather the sections are separatedby tabs. In fact, there are tabs for CNC Machining as well as welding even though in the present state nothing hasbeen included for either section. The authors of this project have limited to no experience in either section, so it issuggested that future work for this project includes someone with experience in these topics adding notes to thissection.

Lean Manufacturing Mentor GuideShop Orientation/SafetyThe first day of Lean Manufacturing is a shop orientation for the students. This is required for them to be shopcertified so that they can work in the shop under a mentor’s guidance. The shop orientation checklist can be foundon the Machine Shop website. As a mentor, it is advised to read through the document prior to giving an orientationso that you can be prepared to answer any questions and have a plan for what to talk about in each section. Includedbelow are notes to help with the manual lathe and mill:Manual LatheChanging jaws in 3-jaw chuckChanging to collet chuck on lathe #1Changing from 3-jaw to 4-jaw chuckUsing a live center.Use for long parts to prevent deflection (a part in the lathe is a cantilever beam)Tools and tool holders (Kept in drawers)Cuts are made from diameter NOT radiusSetting tool heightsWhich tools to useBoring bar, reamer, drill, countersink, etc.Carbide Vs. high speedCarbide is used for harder materials such as steel while high speed is used for softer materials such asaluminumChanging from high range to low rangeChange only when the machine is NOT runningSpeed control (Change ONLY when lathe is running).Reference charts to pick correct speedLead screw (engage only when lathe is NOT running).Speeds and feeds, power feeds (longitudinal and traverse)Z travel indicator

Lean Manufacturing Mentor GuideSetting and adjusting the compound restNo long parts protruding out of headstock unsupportedCarriage LockLean Manufacturing Mentor GuideAgain, parts in the lathe are a cantilever beam; the shorter the part the smaller the momentManual Mill:D.R.O’s (digital read only)Show how to zero, can be used for extremely precise mill operationsSpeed change (belts and high/low)DO NOT adjust when motor is not running. Low speed runs in reverse. See cutting speed chartsfor speed to use –reaming tools run at half of the speed shown on the chartVise, hold down clamps, parallels, lead hammers, and indicatorsLocated in cabinet next to Russ’s office. Use hammers to get parts flat in vice and parallels for cutsabove vise jaws. Clamps used for weird geometry parts that the vise can’t hold down wellenough.Do not leave vise sitting on mill and not bolted downTram, tilt headClampsEdge findersMake sure to account for .2 dia. (move .1 further after zeroing, zero again)Filing, deburring partsMetal is sharp when cut, make sure to file/debur when cut is finishedFinishesClimb cut for smooth finishPower feeds (x,y,z)Do not leave power feed speed-control dials turned up when finished withThis could mess up somebody else’s part.mill for the day

Lean Manufacturing Mentor GuideBoring headIn the grey cabinet next to mill 1.Right angle headNot really used, but in the cabinets by scrap metal if a student asks. Used for long parts that can’t fitunder mill.Spindle key for collets, drill chucks, etc.Keep chips swept back to avoid tracking throughout the shopGeneral Lathe Tips Always double check to make sure your work is securely clamped in the chuck or between centers before startingthe lathe. Start the lathe at low speed and increase the speed gradually. Get in the habit of removing the chuck key immediately after use. Some users recommend never removing yourhand from the chuck key when it is in the chuck. The chuck key can be a lethal projectile if the lathe is started withthe chuck key in the chuck. Keep your fingers clear of the rotating work and cutting tools. This sounds obvious, but don’t try breaking awaymetal spirals as they form at the cutting tool. You must consider the rotational speed of the workpiece and the movement of the tool relative to the workpiece.Basically, the softer the metal the faster the cutting. One of the great features of the lathe is that you can adjust the rotational speed without stopping to changegears. Most cutting operations will be done with the HI/LO gear in the LO range. Higher speeds, and particularlythe HI range, are used for operations such as polishing, and cutting aluminum and brass. To gain a good understanding of the lathe, you will need to know the names of the various components, asillustrated below. The carriage, in the circled area, consists of the apron, the vertical casting on which the carriagehand wheel is mounted, and the saddle (not shown), the H-shaped casting that rides on the ways to which theapron is attached.

Lean Manufacturing Mentor GuideClutchLeverLean Manufacturing Mentor GuideGlossary of Lathe TermsApronFront part of the carriage assembly on which the carriage hand-wheel is mountedBedMain supporting casting running the length of the lathe1.A method of holding a workpiece by mounting it between a center in theheadstock spindle and a center in the tailstock spindle (see Center).Between Centers 2.A dimension representing the maximum length of a workpiece that can beturned between centers.CarriageAssembly that moves the Toolpost and cutting tool along the waysCarriageHandwheelA wheel with a handle used to move the carriage by hand by means of a rack and pinion driveCarriage LockA mechanism for locking the carriage to the ways so that the saddle does not move along theways during facing operations.CenterA precision ground tapered cylinder with a 60º pointed tip and a Morse Taper shaft. Used in thetailstock to support the end of a long workpiece. May also be used in the headstock spindle tosupport work between centers at both ends. Also the process of positioning a workpieceaccurately in line with a drill or mill.

Lean Manufacturing Mentor GuideCenter Drill1.A short, stubby drill used to form a pilot hole for drilling and a shallow countersunk holefor mounting the end of a workpiece on a center.2.The process of drilling a workpiece with a center drillClutch LeverLever to engage the carriage with the leadscrew to move the carriage under powerChuckA clamping device for holding work in the lathe or for holding drills in the tailstock.CompoundMovable platform on which the Toolpost is mounted; can be set at an angle to the workpiece.Also known as the compound slide and compound rest.CompoundHandwheelA wheel with a handle used to move the compound slide in and out. Also known as the compoundfeed.Countersink1.To form a shallow, cone-shaped hole surrounding a smaller diameter drilled hole. Acountersink is often used so that the head of a flat-head screw will be flush with, or slightly below,the surface in which the screw is being used.2.A cutting tool, similar to a drill bit, with a cone-shaped tip, used to cut a countersink hole.Often combined with a short drill bit tip as a "combination drill and countersink", or center drill.Cross FeedtheA hand-wheel or crank that moves the cross-slide by turning a screw. Also the action ofmovingcross slide using the cross feed hand-wheel.Cross SlidePlatform that moves perpendicular to the lathe axis under control of the cross-slide hand-wheelCross-slideA wheel with a handle used to move the cross-slide in and out. Also known as the cross feed.HandwheelCutting ToolThe tool that does the cutting, or removal of metal or other material. May refer to any type ofcutting tool such as a drill, reamer or a lathe bit. A lathe bit typically has a square cross-sectionwith a sharpened tip on one end. It is made from very hard and heat-resistant material such asHigh Speed Steel or a form of carbide.

Lean Manufacturing Mentor GuideFaceplateA metal plate with a flat face that is mounted on the lathe spindle to hold irregularly shaped work.HandwheelA wheel turned by hand to move a component of a lathe or other machine tool. Often will have ahandle extending from the front face. The handle facilitates rapid turning of the hand-wheel.HeadstockThe main casting mounted on the left end of the bed, in which the spindle is mounted. Houses thespindle speed change gears.LeadscrewPrecision screw that runs the length of the bed. Used to drive the carriage under power forturning and thread cutting operations. Smaller leadscrews are used within the cross-slide andcompound to move those parts by precise amounts.Pilot Hole pilotA shallow hole, usually cone-shaped, drilled as a starter hole before drilling a deeper hole.Thehole helps to ensure that the drill bit enters the material at the desired location and does notdrift as the bit starts cutting into the material being drilled.SaddleA casting, shaped like an "H" when viewed from above, which rides along the ways. Along withthe apron, it is one of the two main components that make up the carriage.SpindleMain rotating shaft on which the chuck or other work holding device is mounted. It is mounted inprecision bearings and passes through the headstock.SpindleThroughholeA dimension indicating the minimum diameter of the hole that passes through the spindle. Aworkpiece with a diameter smaller than this can pass through the spindle to facilitate working onlong pieces of work.SwingA dimension representing the largest diameter workpiece that a lathe can rotate. A relateddimension, Swing Over Carriage or Swing Over Cross Slide, is the maximum diameter workpiecethat can rotate over the cross slide.TailstockCast iron assembly that can slide along the ways and be locked in place. Used to hold long work inplace or to mount a drill chuck for drilling into the end of the work.TailstockHandwheelA wheel with a handle used to move the tailstock ram in and out of the tailstock casting.Tailstock RamA piston-type shaft that can be moved in and out of the tailstock by turning the tailstockhandwheel. Has a tapered internal bore to accept a Morse Taper shank. The shaft, or ram, isadvanced or withdrawn by rotating the tailstock hand-wheel located on the right end of thetailstock. The ram can be locked in place at a specific point by a locking lever.ToolA cutting tool used to remove metal from a workpiece; usually made of High Speed Steel orcarbide.ToolpostA holding device mounted on the compound into which the cutting tool is clampedWaysPrecision ground surfaces along the top of the bed on which the saddle rides. The ways areprecisely aligned with the centerline of the lathe.

Lean Manufacturing Mentor GuideLathe Operations Operations that could be done on the LatheFacing - Turning - Drilling - Parting - Boring- Tapping & Threading FacingFacing is the process of removing metal from the end of a workpiece to produce a flat surface. Most often,the workpiece is cylindrical, but using a 4-jaw chuck you can face rectangular or odd-shaped workpiece toform cubes and other non-cylindrical shapes.To safely perform a facing operation the end of the workpiece must be positioned close to the jaws of thechuck because when a lathe cutting tool removes metal it applies considerable tangential (i.e. lateral orsideways) force to the workpiece.The workpiece should not extend more than 2-3 times its diameterfrom the chuck jaws unless a steady rest is used to support the freeend.Preparing for the Facing Cut Clamp the workpiece tightly in the 3-jaw chuck. To get the workproperly centered, close the jaws until they touch the surface ofthe workpiece then use a dial indicator to adjust center line ofthe workpiece, and then tighten the jaws. Choose a cutting tool with a slightly rounded tip. A tool with asharp pointed tip will cut little grooves across the face of theworkpiece and prevent you from getting a nice smooth surface.Clamp the cutting tool in the tool post and turn the toolpost sothat the tip of the cutting tool will meet the end of theworkpiece at a slight angle. It is important that the tip of thecutting tool be right at the centerline of the lathe; if it is too highor too low youwill be left with a little bump at the center of theface. Clamp the Toolpost in place and advance the carriage until the tool is about even with the end of theworkpiece. Make sure that the compound is not all the way at the end of its travel towards the chuck;about midway in its range of travel is good. Beginning the Facing Cut Use the compound hand-wheel to advance the tip of the tool until it just touches the end of theworkpiece. Use the cross feed crank to back off the tool until it is beyond the diameter of theworkpiece. Turn the lathe on and adjust the speed to the proper RPM. Now slowly advance the crossfeed hand-wheel to move the tool towards the workpiece. When the tool touches the workpiece it

Lean Manufacturing Mentor Guideshould start to remove metal from the end. Continue advancing the tool until it reaches the center ofthe workpiece and then crank the tool back in the opposite direction (towards you) until it is back pastthe edge of the workpiece. We started with the tool just touching the end of the workpiece; so we probably removed very littlemetal on this pass. This is a good idea until we get used to how aggressively you can remove metalwithout stalling the lathe. Also, since the end of the workpiece can be very uneven, we want to avoidgouging the tool into the end of the workpiece if it hits a high spot.The Roughing Cut With the tool just touching the end of the workpiece, move thedial indicator into position and lock at 0. Use the dial indicator tomonitor the length of the cuts. Tighten the carriage clamp toprevent the carriage from being pushed away from the end of partwhile facing.Cutting on the Return Pass If you crank the tool back towards you after it reaches the centerof the workpiece you will notice that it removes a small amountof material. You should move away from the part after the finish pass in order to maintain a smoothfinish.

Lean Manufacturing Mentor GuideThe Finishing Cut Depending on how rough the end of the workpiece was to begin withand how large the diameter is, you may need to make 3 or morepasses to get a nice smooth finish across the face. These initial passesare called roughing passes and remove a relatively large amount ofmetal. When you get the face pretty smooth you can make a final finishingcut to remove just .001 to .003" of metal and get a nice smoothsurface. The finishing cut can also be made at higher RPM to get asmoother finish. If the tip of your cutting tool is below the center line of the lathe, alittle nub is left at the center of the workpiece. The same thinghappens if the tool is too high but the nub will have more of a coneshape in that case. If the tool is too low, place a suitable thickness ofshim stock underneath the tool in the tool holder. If it's too high,grind the top down.Filing the Edge Facing operations leave a rather sharp edge on the end of the workpiece. It's a good idea to smooththis edge down with a file to give it a nice chamfer and to avoid cutting yourself on it. With the latherunning at fairly low speed, bring a smooth cut file up to the end of the workpiece at a 45 degree angleand apply a little pressure to the file.Wrong: left hand reaching over spinning chuck!Right - left hand holding tang end of fileThis is what a good facing cut should look like: smooth even surface with noraised bump in the center. Lay an accurate straight edge across the surface of theface and you should not be able to see any light under the edge. If you detect aslight convex shape, the carriage may be moving back away from the headstockduring the cut.

Lean Manufacturing Mentor GuideTurningTurning is the removal of metal from the outer diameter of a rotating cylindrical workpiece. Turning is usedto reduce the diameter of the workpiece, usually to a specified dimension, and to produce a smooth finishon the metal.Chucking the Workpiece We will be working with a piece of 6061 aluminum not too long. A workpiece such as this which isrelatively short compared to its diameter is stiff enough that we can safely turn it in the three jaw chuckwithout supporting the free end of the workpiece. For longer workpieces we would need to face and center drill the free end and use a dead or live centerin the tailstock to support it. Without such support, the force of the tool on the workpiece would causeit to bend away from the tool, producing a strangely shaped result. There is also the potential that thework could be forced to loosen in the chuck jaws and fly out as a dangerous projectile. Insert the workpiece in the 3-jaw chuck and tighten down thejaws until they just start to grip the workpiece. Rotate theworkpiece to ensure that it is seated evenly and to dislodge anychips or grit on the surface that might keep it from seatingevenly. You want the workpiece to be as parallel as possible withthe center line of t

Shop Orientation/Safety The first day of Lean Manufacturing is a shop orientation for the students. This is required for them to be shop certified so that they can work in the shop under a mentor’s guidance. The shop orientation checklist can be found on the Machine Shop website.

Related Documents:

Bruksanvisning för bilstereo . Bruksanvisning for bilstereo . Instrukcja obsługi samochodowego odtwarzacza stereo . Operating Instructions for Car Stereo . 610-104 . SV . Bruksanvisning i original

sustainability of lean manufacturing tools and techniques are also discussed. This is an overview for finding the current situation of lean management practices in manufacturing industries. Apply lean in a production and safe environment Fig.2.Methodology of lean manufacturing technique FOUR PILLARS OF LEAN MANUFACTURING JIT(Just In Time)

Lean Six Sigma Yellow Belt provides a detailed information on the Lean Six Sigma fundamentals and ways to apply Lean Six Sigma to specific industry to achieve desired results. LEAN MANAGEMENT 1.0 Introduction to Lean 2.0 What is Lean & Application of Lean

18.2 Lean and Agile Manufacturing Paradigms for Academia 242 18.3 Lean and Agile Manufacturing Paradigms for Consultants 242 18.4 Lean and Agile Manufacturing Paradigms for Practising Engineers 243 18.5 Lean and Agile Manufacturing Paradigms for Practising Managers243 18.6 L

The Lean Enterprise Institute lays out a 5-step cycle for implementing lean: 7 The Lean Manufacturing Cycle The Lean Enterprise Institute's 5-Step Lean Manufacturing Cycle 1. Specify value from the standpoint of the end customer by product family. 2. Identify all the steps in the value stream for each product

2.3.3 Lean Manufacturing 40 . 2.3.4 Lean Warehousing 40 . 2.3.5 Lean Transportation 41 2.3.6 Lean Customers 43 . 2.4 Barriers and Drawbacks 43 . A STUDY ON LEAN SUPPLY CHAIN IMPLEMENTATION IN MALAYSIA'S ELECTRICAL AND ELECTRONICS INDUSTRY: PRACTICES AND PERFORMANCES . LEAN . Management Management Supply Chain

10 tips och tricks för att lyckas med ert sap-projekt 20 SAPSANYTT 2/2015 De flesta projektledare känner säkert till Cobb’s paradox. Martin Cobb verkade som CIO för sekretariatet för Treasury Board of Canada 1995 då han ställde frågan

service i Norge och Finland drivs inom ramen för ett enskilt företag (NRK. 1 och Yleisradio), fin ns det i Sverige tre: Ett för tv (Sveriges Television , SVT ), ett för radio (Sveriges Radio , SR ) och ett för utbildnings program (Sveriges Utbildningsradio, UR, vilket till följd av sin begränsade storlek inte återfinns bland de 25 största