injection moulding lab manual

injection moulding lab manual

Related documents Pmbok 7 A textbook of machine design khurmi gupta Marking Scheme - dont open Mechanics of Materials 4th Edition Beer Johnston Solution Manual Experiment 6 - Thin Cylinder a.thermodynamics Preview text ABSTRACT Injection moulded components are consistently designed to minimize the design and manufacturing information content of the enterprise system. The resulting designs, however, are extremely complex and frequently exhibit coupling between multiple qualities attributes. Axiomatic design principles were applied to the injection moulding process to add control parameters that enable the spatial and dynamic decoupling of multiple quality attributes in the moulded part. There are three major benefits of the process redesign effort. First, closed loop pressure control has enabled tight coupling between the mass and momentum equations. This tight coupling allows the direct input and controllability of the melt pressure. Second, the use of multiple melt actuators provides for the decoupling of melt pressures between different locations in the mould cavity. Such decoupling can then be used to maintain functional independence of multiple qualities attributes. Third, the heat equation has been decoupled from the mass and momentum equations. This allows the mould to be filled under isothermal conditions. Once the cavities are completely full and attain the desired packing pressure, then the cooling is allowed to progress. INTRODUCTION Injection molding is the most commonly used manufacturing process for the fabrication of plastic parts. A wide variety of products are manufactured using injection molding, which vary greatly in their size, complexity, and application. The injection molding process requires the use of an injection molding machine, raw plastic material, and a mold. The plastic is melted in the injection molding machine and then injected into the mold, where it cools and solidifies into the final part.http://www.bmsk.ru/images/static/dodge-cummins-manual-for-sale.xml

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The steps in this process are described in greater detail in the next section. Injection molding is used to produce plastic parts for a wide variety of applications, one of the most common being plastic housings. Plastic housing is a enclosure, often requiring many ribs and bosses on the interior. These housings are used in a variety of products including household appliances, consumer electronics, power tools, and as automotive dashboards. Other common products include different types of open containers, such as buckets. Injection molding is also used to produce several everyday items such as toothbrushes or small plastic toys. Many medical devices, including valves and syringes, are manufactured using injection molding as well. HISTORY AND DEVELOPMENT The first plastic was invented in Britain in 1851 Alexander Parkes. He publicly demonstrated it at the 1862 International Exhibition in calling the material he produced Derived from cellulose, Parkesine could be heated, molded, and retain its shape when cooled. It was, however, expensive to produce, prone to cracking, and highly flammable. In 1868, American inventor John Wesley Hyatt developed a plastic material he named Celluloid, improving on invention so that it could be processed into finished form. Together with his brother Isaiah, Hyatt patented the first injection molding machine in 1872. This machine was relatively simple compared to machines in use today. It worked like a large hypodermic needle, using a plunger to inject plastic through a heated cylinder into a mold. The industry progressed slowly over the years, producing products such as collar stays, buttons, and hair combs. The industry expanded rapidly in the 1940s because World War II created a huge demand for inexpensive, products. In 1946, American inventor James Watson Hendry built the first screw injection machine, which allowed much more precise control over the speed of injection and the quality of articles produced.http://www.asv-solnice.cz/_files/compaq-prosignia-165-manual.xml

This machine also allowed material to be mixed before injection, so that colored or recycled plastic could be added to virgin material and mixed thoroughly before being injected. Today screw injection machines account for the vast majority of all injection machines. In the 1970s, Hendry went on to develop the first injection molding process, which permitted the production of complex, hollow articles that cooled quickly. This greatly improved design flexibility as well as the strength and finish of manufactured parts while reducing production time, cost, weight and waste. The plastic injection molding industry has evolved over the years from producing combs and buttons to producing a vast array of products for many industries including automotive, medical, aerospace, consumer products, toys, plumbing, packaging, and construction. PROCESS CYCLE The process cycle for injection molding is very short, typically between 2 seconds and 2 minutes, and consists of the following four stages: 1. Clamping Prior to the injection of the material into the mold, the two halves of the mold must first be securely closed the clamping unit. Each half of the mold is attached to the injection molding machine and one half is allowed to slide. The hydraulically powered clamping unit pushes the mold halves together and exerts sufficient force to keep the mold securely closed while the material is injected. The time required to close and clamp the mold is dependent upon the machine larger machines (those with greater clamping forces) will require more time. This time can be estimated from the dry cycle time of the machine. 2. Injection The raw plastic material, usually in the form of pellets, is fed into the injection molding machine, and advanced towards the mold the injection unit. During this process, the material is melted heat and pressure. The molten plastic is then injected into the mold very quickly and the buildup of pressure packs and holds the material.

The amount of material that is injected is referred to as the shot. The injection time is difficult to calculate accurately due to the complex and changing flow of the molten plastic into the mold. However, the injection time can be estimated the shot volume, injection pressure, and injection power. 3. Cooling The molten plastic that is inside the mold begins to cool as soon as it makes contact with the interior mold surfaces. As the plastic cools, it will solidify into the shape of results from this trimming can be recycled being placed into a plastic grinder, also called regrind machines or granulators, which regrinds the scrap material into pellets. Due to some degradation of the material properties, the regrind must be mixed with raw material in the proper regrind ratio to be reused in the injection molding process. MACHINERY AND EQUIPMENTS ARBURG ALLROUNDER 520C (2007) Model: Year: 2007 Screw diameter: 45mm Shot Weight Max. (PS): 318g Clamping force: Platen size: 728x728mm Distance between tie bars: 520x520mm Control: SELOGICA Working hours (approx.): 2,100hrs MOLD DESIGN The mold or die refers to the tooling used to produce plastic parts in molding. Traditionally injection molds have been expensive to manufacture and were only used in production applications where thousands of parts were produced. Molds are typically constructed from hardened steel, steel, aluminum, alloy. The choice of material to build a mold from is primarily one of economics. Steel molds generally cost more to construct but offer a longer lifespan that will offset the higher initial cost over a higher number of parts made before wearing out.The hardness of the steel measures typically on the scale. Hardened steel molds are heat treated after machining, making them superior in terms of wear resistance and lifespan. Typical hardness ranges between 50 and 60 (HRC).

Aluminum molds cost substantially less than steel molds, and when higher grade aluminum such as and aircraft aluminum is used and machined with modern computerized equipment, they can be economical for molding hundreds of thousands of parts. Aluminum molds also offer quick turnaround and faster cycles because of better heat dissipation. They can also be coated for wear resistance to fiberglass reinforced materials. Beryllium copper is used in areas of the mold which require fast heat removal or areas that see the most shear heat generated. MATERIALS There are many types of materials that may be used in the injection molding process. Most polymers may be used, including all thermoplastics, some thermosets, and some elastomers. When these materials are used in the injection molding process, their raw form is usually small pellets or a fine powder. Also, colorants may be added in the process to control the color of the final part. The selection of a material for creating injection molded parts is not solely based upon the desired characteristics of the final part. While each material has different properties that will affect the strength and function of the final part, these properties also dictate the parameters used in processing these materials. Each material requires a different set of processing parameters in the injection molding process, including the injection temperature, injection pressure, mold temperature, ejection temperature, and cycle time. 1) Polypropylene (PP) Polypropylene is a very useful plastic for injection molding and is typically available for this purpose in the form of pellets. Polypropylene is easy to mold despite its nature, and it flows very well because of its low melt viscosity. This property significantly enhances the rate at which you can fill up a mold with the material.

Shrinkage in polypropylene is about but can vary based on a number of factors, including holding pressure, holding time, melt temperature, mold wall thickness, mold temperature, and the percentage and type of additives. Polypropylene is available in many grades including: glass and mineral filled homopolymer and random copolymer visions flame retardant grades and specialty grades. The material in its natural state is translucent and can be molded in an unlimited number of colors. Polypropylene is also available in many melt flow rates ranging from less than 1 to over 60 As the melt flow increases, the ability to mold thin wall parts increases while the mechanical properties of polypropylene exhibit some reduction. The copolymer versions of polypropylene offer enhanced mechanical properties at low temperatures, particularly impact strength. Design flexibility. Repeatability within tolerance. Can process wide range of materials. Relatively low labour. Minimum scrap losses. DISADVANTAGES High initial equipment investments. High start up and running cost possible. Parts must be designed for effective molding. Accurate cost prediction for molding job is difficult. DEFECTS IN INJECTION MOLDING Warping The permanent bending of a part that occurs when certain section of the part shrink faster than others, as result of a cooling rate. Bubbles Once the test is executed, the settings for both material were then inserted into the machine for the injection process. Both material has different settings as they are not from the same type. The table below shows the comparison between the ABS material and polypropylene (pp) material.

Table: Parameters setting of 6 cavity card holder mold Material ABS PP Dry Temperature 80oC Screw Barrel Temperature Mold Temperature 50oC Clamping Force 972 kN Shot Capacity 53 51 Injection 50 50 Injection Pressure 600 150 Cushion 8 8 Holding Flow 25 25 Holding Pressure 300 75 Complete product Incomplete product CONCLUSION Injection molding is one of the most important processes for plastics and it has a very wide list of kinds of products it can produce, which makes it very versatile. REFERENCES 1. MENGES MICHAELI How to Make Injection Third Cincinnati, 2001 2. RICHARDSON Industrial Plastics, Theory and Third Delmar Publishers Albany, NY, 1997 3. BERNIE A. OLMSTED MARTIN E. Practical Injection New York, 2001 4. MANUFACTURING Prof. P.N. Rao, Univarsiti Mara, Shah Alam, Malasia. Discover everything Scribd has to offer, including books and audiobooks from major publishers. Start Free Trial Cancel anytime. Report this Document Download Now Save Save ME2207 MANUFACTURING TECHNOLOGY I LAB MANUAL For Later 91% (11) 91% found this document useful (11 votes) 7K views 71 pages ME2207 MANUFACTURING TECHNOLOGY I LAB MANUAL Uploaded by Karthick N Description: ME2207 MANUFACTURING TECHNOLOGY I LAB MANUAL Full description Save Save ME2207 MANUFACTURING TECHNOLOGY I LAB MANUAL For Later 91% 91% found this document useful, Mark this document as useful 9% 9% found this document not useful, Mark this document as not useful Embed Share Print Download Now Jump to Page You are on page 1 of 71 Search inside document Browse Books Site Directory Site Language: English Change Language English Change Language. Discover everything Scribd has to offer, including books and audiobooks from major publishers. Start Free Trial Cancel anytime.

Report this Document Save Save Injection Molding Lab Manual Up (1) For Later 0 ratings 0% found this document useful (0 votes) 9 views 3 pages Injection Molding Lab Manual Up (1) Uploaded by Anonymous asGPbP Description: werwerwer Full description Save Save Injection Molding Lab Manual Up (1) For Later 0% 0% found this document useful, Mark this document as useful 0% 0% found this document not useful, Mark this document as not useful Embed Share Jump to Page You are on page 1 of 3 Search inside document Browse Books Site Directory Site Language: English Change Language English Change Language. If you continue browsing the site, you agree to the use of cookies on this website. See our User Agreement and Privacy Policy.If you continue browsing the site, you agree to the use of cookies on this website. See our Privacy Policy and User Agreement for details.If you wish to opt out, please close your SlideShare account. Learn more. You can change your ad preferences anytime. My professor asked me to write a research paper based on a field I have no idea about. My research skills are also very poor. So, I thought I’d give it a try. I chose a writer who matched my writing style and fulfilled every requirement I proposed. I turned my paper in and I actually got a good grade. I highly recommend ? www.WritePaper.info ?Save so as not to loseThey actively want to take part and figure out what they need to do. I really love this approach to dog training and my dogs do too! ??? Design And Experiment Project Laboratory Report. Influence Of Injection Molding Parameter On The Mechanical AndInjection molding is a process in which polymer is heated to highly plastic state andThe process produces discrete components that are almost always net shape.

Complex and intricate shapes are possible with injection molding the limitation beingInjection molding is the mostTesnsile test also known as tension test, is probably the most fundamental type ofTensile tests are simple, relativelyBy pulling on something, very quickly determineAs the material is beingThe Rockwell scale is a hardness scale based on the indentation hardness of a material. The Rockwell test determines the hardness by measuring the depth of penetration ofThe hardness values obtained are useful indicators of a material’s properties andThe theory of injection molding can be reduced to five simple individual steps. Plasticizing, Injection, Packing, Chilling, and Ejection. Each step is distinct from theAs the materialFor most tensile testing of materials, the relationship between the applied force andIn this linear region, the line obeys theThe modulus of elasticity is a measure of the stiffness of the material, onlyLoading within this linear region, theHooke's Law noThe Rockwell hardness test method consists of indenting the test material with aThe indenter is forced into the testWhile the preliminary minor load is still applied an additional major load isRemoval of the additional major load allows a partial recovery, so reducing theClamping force refers to the force applied to a mold by the clamping unit of anIn order to keep the mold close, this force must opposeThe calculated tonnageA ? safety coefficient (? 1.5)The approximate shape and dimension of the moldThe Taguchi method involves reducing the variation in a process through robustThe overall objective of the method is to produce high qualityThe Taguchi method was developed by Dr. Genichi Taguchi of Japan who maintained that variation. Taguchi developed a methodThe experimental design proposed by Taguchi involves using orthogonal arraysThis allows for the collectionTaguchi experiments often use a 2-step optimization process. In step 1 use the. In step 2, identifyWe can choose from.

For static designs. Signal-to-noise ratio Use when the goal is to: And the data are. Larger is better Maximize the response Positive. Nominal is best Target the response and youPositive, zero, or negative. Nominal is bestTarget the response and youNon-negative with anSmaller is better Minimize the response Non-negative with a targetStep 1: Designing the ExperimentLevels. FactorsLevel 1 ( A ) Level 2 ( B ) Level 3 ( C ). Step 2: Setup the values of parameterThe A, B and C represent the values to be tested for each parametersStep 3: Perform Taguchi AnalysisFunctions. Perform the injection molding process through heating a plastic to its glassWhen the polymer solidified, the molding is then being removed from cavity where itSpecification. Machine PropertiesFunction:Specification:Frame SpecificationFunction. The general Rockwell test procedure is the same regardless of the Rockwell scale orAfter the measurement is made, an additional amount of force is applied at a setAfter holding theThe data that used in experiment:Function. The Scanning Electron Mircoscope is capable to produce high resolution image of aSpecification:Minitab is a statistic package which able to create a Taguchi Experimental design. Data being inserted can be converted into graph and undergo varies of analysis. Utilization Guideline:For Levels, choose the number of mostLn S. Std Deviation, S. MeanThe mixture ratio between Polystyrene and Polyethylene is 50:50.Polypropylene (PP), also known as polypropene, is a thermoplastic polymer, made byAn addition polymer made from the monomerMechanical PropertiesThermal PropertiesPolyethylene is an inexpensive and versatile polymer with numerous applications. Control of the molecular structure leads to low density (LDPE), linear low densityMechanical PropertiesThermal PropertiesParts, Surface imperfection, Flashing, Shrinkage voids and Internal voids.Flashing, Brittleness of molded parts.

The usage of theInjection temperature and Injection speed of the recipocating screw.The value of each set ofTake the data from UTM’s computer after experiment. Find out Young’sFigure 8.4 Example of the software being utilized to oeprate the Hitachi TM-1000Levels. ParametersLevel 1 ( A ) Level 2 ( B ) Level 3 ( C )From technician, given that the. Thus, the adjustment is shown in the table below. Levels. ParametersLevel 1 ( A ) Level 2 ( B ) Level 3 ( C )Set No. 1. Set No. 2. Set No. 3. Set No. 4. Set No. 5. Set No. 6. Set No. 7. Set No. 8. Set No. 9Set. No. Hardness ( HRL ) Mean,Deviation, S. Ln S. RatioTest 1, x1 Test 2, x2 Test 3, x3Parameter. Mean of Means. Range. Level 1 (A) Level 2 ( B) Level 3 ( C ). Pressure, bar 29.244 5.844 18.456 23.400. Temperature, oExample of Calculation. Pressure Temperature Speed. Set No. Mean, ?From the data table 9.21, the graph for Mean of Means for Hardness against Level of. Factor is plotted through Minitab software as shown in figure 9.21 above. The range of of mean for Pressure, Temperature and Speed are 23.400, 9.523From the graph, we can easily observe and compare the mean value for eachIn order to maximize the hardness, we shall set Pressure at level 1 ( 50 bar ). Temperature at level 1 ( 230 ?C ) and Speed at level 1 ( 60 rpm ) during the Injection. Molding Process.Parameter. Mean of Ln S. Range. Level 1 (A) Level 2 ( B) Level 3 ( C ). Pressure, bar 0.81252 -0.36061 0.65100 1.1731. Temperature, oExample of Calculation. Pressure Temperature Speed. Set No. Ln SFrom data table 9.22, the graph for Mean of Natural Logarithm ( Ln ) Standard. Deviation for Hardness against Level of Factor is plotted through Minitab software asThe range of Ln Standard Deviation for Pressure, Temperature and Speed areFrom the graph, we can easily observe and compare the Ln Standard DeviationThe lowest Ln Standard Deviation value is selected since itIn order to minimize the hardness variability, weRange. Level 1 (A) Level 2 ( B) Level 3 ( C ).

Pressure, bar 29.05 14.84 24.45 14.21. Temperature, oExample of Calculation. Pressure Temperature SpeedAn improvement in the process is signified by an increase in the Signal-to-Noise. Hence, the selectedSource of Degree of Sum of Square Mean Square Percentage. Variation Freedom SSp. Contribution. Pressure 2 315.4362 157.7181 7.9241 82.65. Temperature 2 7.6443 3.8222 0.192 2.00. Speed 2 18.7566 9.3783 0.4712 4.91. Error 2 39.8073 19.9037 - 10.44. Total 8 381.6444 100. F-Ratio. Example of Calculation. Set No.Formula:The objective of taguchi analysis is to increase the means, reducing the Ln( S ). For ease of identifying the strong effect andFinal. Pressure 1 2 1 1. Temperature 1 1 1 1. Speed 1 3 3 3. Parameter. Optimized Level. Table 9.25 Summary Table of the optimized level based on different parameterIn this case, reduction in Ln (S) appear insignificantly. For Temperature we can easily determine e the final optimized level which is. Level 1 since the optimized level is same for all three responses ( Mean, Ln(S) and. However, level 1 is maxizing for Means. In this case, Maxizing for Means appearAs a conclusion, the final optimized level for each parameter to acquire the mostPercentage Overall. Pressure 7.9241 82.65 1 1 1 1. Temperature 0.192 2.00 2 2 3 2. Speed 0.4712 4.91 3 3 2 3. F-Ratio. Rank ( based on the range ). Parameter. Table 9.26 Summary Table of the rank,F-ratio and %Contribution against parameters. The F-ratio test is a ratio of mean square of each parameter and mean square of errorF-ratio is larger if the parameter has greaterPressure with the ratio of 7.9241, while 0.4712 for Speed and the lowest is. Temperature which gives a ratio of 0.192. Meanwhile, Percentage Contribution is to show how big the effects of controlForm the table above, the highestHowever, from Table 9.26, the higest overall ranking is Pressure, the second is. Temperature and the lowest is speed. It has a different ranking because F-ratio and.

Percentage Contribution had included the Error which is more accurate.No. Tensile Strength ( MPa ). Mean. Standard. Deviation, S. Example of Calculation ( For Set No. 1 ):Parameter. Mean of Means. Range. Level 1 (A) Level 2 ( B) Level 3 ( C ). Pressure, bar 22.89 34.93 29.03 12.05. Temperature, oExample of Calculation. Pressure Temperature Speed. Set No. Mean, ?From the data table 9.31, the graph for Mean of Means for Tensile Strength against. Level of Factor is plotted through Minitab software as shown in figure 9.31 above. The range of of mean for Pressure, Temperature and Speed are 12.05, 1.75 andFrom the graph, we can easily observe and compare the mean value for eachTemperature at level 3 ( 270 ?C ) and Speed at level 2 ( 72 rpm ) during the Injection. Molding Process.Parameter. Mean of Ln S. Range. Level 1 (A) Level 2 ( B) Level 3 ( C ). Pressure, bar -0.7882 1.1595 0.2294 1.9477. Temperature, oExample of Calculation. Pressure Temperature Speed. Set No. Ln SFrom data table 9.32, the graph for Mean of Natural Logarithm ( Ln ) Standard. Deviation for Tensile Strength against Level of Factor is plotted through MinitabThe range of Ln Standard Deviation for Pressure, Temperature and Speed areFrom the graph, we can easily observe and compare the Ln Standard DeviationThe lowest Ln Standard Deviation value is selected since itIn order to minimize the tensile stressParameter. Range. Level 1 (A) Level 2 ( B) Level 3 ( C ). Pressure, bar 27.14 31.41 29.23 4.27. Temperature, oExample of Calculation. Pressure Temperature SpeedAn improvement in the process is signified by an increase in the Signal-to-Noise. Hence, the selectedSource of Degree of Sum of Square Mean Square Percentage. Variation Freedom SSp. Contribution. Pressure 2 27.353 13.677 8.739 83.88. Temperature 2 0 0 0 0.00. Speed 2 2.128 1.064 1.025 6.53. Error 2 3.129 1.565 - 9.59. Total 8 32.61 100. F-Ratio. Example of Calculation. Set No.

Formula:The objective of taguchi analysis is to increase the means, reducing the Ln( S ). For ease of identifying the strong effect andFinal. Pressure 2 1 2 2. Temperature 3 2 - 3. Speed 2 3 2 2. Parameter. Optimized Level. Table 9.35 Summary Table of the optimized level based on different parameterIn this case, reduction in Ln (S) appear insignificantly. For the Temperature, level 3 is maxizing for means but level 2 is to reduce the Ln. In this case, We decide to choose level 3 as final optimized level since means is moreIn this case, reduction in Ln (S) appear insignificantly. As a conclusion, the final optimized level for each parameter to acquire the mostPercentage Overall. Pressure 8.739 83.88 1 1 1 1. Temperature 0 0.00 2 2 3 2. Speed 1.025 6.53 3 3 2 3. F-Ratio. Rank ( based on the range ). Parameter. Table 9.36 Summary Table of the rank,F-ratio and %Contribution against parameters. The F-ratio test is a ratio of mean square of each parameter and mean square of errorF-ratio is larger if the parameter has greaterPressure with the ratio of 8.739, while 1.025 for Speed and the lowest is TemperatureMeanwhile, Percentage Contribution is to show how big the effects of controlForm the table above, the highestHowever, from Table 9.36, the higest overall ranking is Pressure, the second is. Temperature and the lowest is speed. It has a different ranking because F-ratio and. Percentage Contribution had included the Error which is more accurate.Specimen 1-4,Magnification ?100. Specimen 1-4,Magnification ?300Specimen 2-4,Magnification ?100. Specimen 2-4,Magnification ?300Specimen 3-1,Magnification ?100. Specimen 3-1,Magnification ?300Specimen 4-2,Magnification ?100. Specimen 4-2,Magnification ?300Specimen 5-3,Magnification ?100. Specimen 5-3,Magnification ?300Specimen 6-3,Magnification ?100. Specimen 6-3,Magnification ?300Specimen 7-5, Magnification ?100. Specimen 7-5, Magnification ?300Specimen 8-5, Magnification ?100. Specimen 8-5, Magnification ?

300Specimen 9-1, Magnification ?100. Specimen 9-1, Magnification ?300Sample 9.1, 300X. The microstructure show that the structure of the specimen does not deform duringThe crack is propagated across the surfaceSample 1.4, 300X. The microstructure show the structure of the specimen try to deform during fractureThis type ofFrom the Scanning Electron Microscope ( SEM ), we also can observe the failureSampel 7.5, 300X. The circles show the origin of crack and the arrows show how they propagate. Sampel 8.5, 100X. The circle show the path of crack propagate.The Green circle is Brittle area, while the Red circle is Ductile area.Set 4 (1049.71MPa) and lowest value is specimens Set 1 (512.885MPa).Old or damaged equipments and instruments will cause error. The readingThe reasons of why the Tool and Instrument error occur are:For example, the. Rockwell hardness unit for polymer should be HRL.For example, theParallax error occur during measuring where it is caused by students duringTo avoid parallax error, the eyes ofIt is either random error or systematic error, which are happen frequentlySystematic errors are errors that produce a result that differs from the trueThese errors are caused by imperfect calibration ofFor example, the condition of injection molding is very hot, while theAlthough the difference of temperature is not very high, shrinkage and change ofThe zero error which is one of the systematic error is due to the calibration onThe reading need to be set back to zero when specimen is changing. If the cause of theRandom error is caused by unpredictable fluctuations in the readings of aWhen testing the specimens during the tensile test, strains are usually too small to beMeasuring small strains typical of a high-strength metals test—0.0001 inch or less—isIf yield values are incorrect, review the stress-strainWedge action grips are the most common style used in specimens testing. As theThe grip faces should be inspected periodically.https://cfdcnv.com/images/brady-200mvp-plus-manual.pdf