DMY00007ENmoss8006.docx

1、DMY00007ENmoss8006Injection Moulded Plastic Parts - MOSS 800/6Global Directive - Mechanical ProcessContents :1. PURPOSE2. DEFINITION3. INSPECTION OBJECTS Suck Dent or bump Convexity or concavity Bent Twist Bursts Incomplete compression Joint seam/cold seam Feed-in marks Flowing marks Hardness/stiffn

2、ess Brittleness Burning marks ”Silver line” Scratches Side scratches Shine errors Bubbles/splinters Colour error Match error Impurities Remains of loosening material Refraction error Uniformity of outer appearance Wearing of electro eroded surfaces4. CAPTIONS The captions must contain: Caption examp

3、leInjection Moulded Plastic Parts - MOSS 800/61. PURPOSEThe purpose of this standard is to. Describe the quality requirements in different quality classes. It also comprises some of the most common defects with their causes so that they can be prevented in design and production phases. Make the capt

4、ions uniform.Note 1. Quality classification of surfaces is defined in MOSS 800/1.2. DEFINITION3. INSPECTION OBJECTS. Suck. Dent or bump. Convex/concave. Bent. Twist. Bursts. Incomplete compression. Joint seam/cold seam. Feed-in marks. Flowing marks. Hardness/stiffness. Brittleness. Burning marks. ”S

5、ilver line”. Scratches. Side scratches. Shine errors. Bumps/splinters. Colour errors. Match error. Impurity. Remains of loosening materials. Refraction error. Uniformity of outer surfaces. Wearing of electro eroded surfacesSuckDefinitionA moderate dent in coating with a possible shiny area. It is ca

6、used . by non-simultaneous cooling of parts with different thicknesses or too quick a cooling.Inspection is carried out visually.Requirements:Class I:No defects allowedClass II:Moderate defects are allowed if they are noticeable through reflection only Class III:Defects can be allowed if they do not

7、 disturb assembly or useDent or bumpDefinitionA gentle-edged deviation from unbroken surface level. It is caused . by wrong handling in production process. . a bump caused by a tool when pressing the part out.Inspection is carried out visually.Requirements:Class I:No defects allowedClass II:Moderate

8、 defects are allowed if they are noticeable through reflection onlyClass III:Dents or bumps can be allowed if they do not disturb assembly or useConvexity or concavityDefinitionThe surface is completely convex or concave (dent or bump). This is caused . by work method or malfunction of tool.Inspecti

9、on is carried out visually or by measuring.Requirements:Class I:No defects allowedClass II:Minor defects are allowed. The tolerances must be respectedClass III:Can be allowed if it does not disturb assembly or useBentDefinitionThe whole part is bent. This is caused . by wrong handling in cooling pha

10、se.Inspection is carried out visually or by measuring.Requirements:Classes I and II:No defects allowed The tolerances must be respectedClass III: Can be allowed if it does not disturb assembly or useTwistDefinitionPart of the object is twisted. This is caused . by wrong handling in cooling phase.Ins

11、pection is carried out visually or by measuring.Requirements:Classes I and II:No defects allowed. The tolerances must be respectedClass III: Gentle defects allowed if they are noticeable through reflection only and they do not disturb assembly or useBurstsDefinitionAn extra burst of material not bel

12、onging to the part. This is caused . by a faulty tool or the overpressure used in compression.Inspection is carried out visually or by measuring.Requirements:Classes I and II:No defects allowedClass III:Gentle bursts allowed if they do not disturb assembly or use and they do not get loose in assembl

13、y or useIncomplete compressionDefinitionThe part has no complete form. This is caused . by insufficient removal of gases.Inspection is carried out visually.Requirements:Classes I and II:No defects allowedClass III:Gentle defects are allowed if they do not disturb assembly or use Definition is made b

14、y reference models or instructions for incoming inspectionJoint seam/cold seamDefinitionA line-like colour error. This is caused . by joint of cold material flows.Inspection is carried out visually.Requirements:Class I:No defects allowedClass II and III:Minor defects allowed if durability is not dec

15、reased The durability has to be proved by testsFeed-in marksDefinitionColour tone differences right by the feed in point. It is caused . by wrong compression process.Inspection is carried out visually.Requirements:Class I:No defects allowed.Class II:Minor defects allowed.Class III:Defects can be all

16、owed if they do not disturb assembly or use.Flowing marksDefinitionColour tone differences in the surface. This is caused . by wrong compression process.Inspection is carried out visually. Requirements:Class I:No defects allowed.Class II:Minor defects allowed.Class III:Defects can be allowed if they

17、 do not disturb assembly or use.Hardness/stiffnessDefinitionDeviation from the defined raw material values. This is caused . by wrong raw material or the mixture ratio.Inspection is carried out visually.Requirements:Classes I, II and III:No deviation allowed.Note! Caption of hardness is marked if ne

18、eded (especially in case of soft materials).BrittlenessDefinitionDeviation from breaking durability differing from those defined for the raw material.Inspection is carried out by testing.Requirements:Classes I, II and III:No deviation allowed.Burning marksDefinitionSensitivity to scratches. This sho

19、ws in tone differences. In difficult cases there are form defects. This is caused . by overheating of the material or by old / recycled raw material.Inspection is carried out visually or by feeling.Requirements:Classes I and II:No defects allowed.Class III:Minor defects allowed if they do not decrea

20、se the durability. The durability must be proved by tests.”Silver line”DefinitionColour tone stripes or dots in the surface. This is caused . by evaporation of humidity in the raw material or burnt raw material.Inspection is carried out visually.Requirements:Minor defects are allowed if the durabili

21、ty of the part is not decreased. This must be proved by tests.ScratchesDefinitionDefected surface. This is caused . by wrong handling.Inspection is carried out visually.Requirements:Class I:No defects allowed.Class II:Minor scratch, which is defined by a reference model, can be allowed.Class III:Can

22、 be allowed.Side scratchesRequirements:Class I and II:Minor defect, which is defined by a reference model, can be allowed.Class III:Can be allowed.Shine errorsDefinitionDeviations appearing as shiny areas from the defined roughness of the surface. This is caused . by temperature differences in mould

23、.Inspection: This is carried out by means of a reference model and/or defined measurement value.Requirements:Definition is performed by reference models, classes I, II and III.Bubbles/splintersDefinitionPores inside the raw material. Appear as distortion in transparent parts. This is caused . by eva

24、poration of impurities in raw material.Inspection is carried out visually.Requirements:Class I:No defects allowed.Class II and III:Bubbles/splinters are allowed if they do not affect outer appearance or durability.Colour errorDefinitionDeviation from defined colour value. At its worst, this is cause

25、d by use of mixing method.Colour, colour tone and patternThese are inspected by means of approved reference model and/or a defined measurement value.Requirements:Classes I and II:No noticeable defects allowed either when checked visually or when measured. Especially the parts to be joined must match

26、 colourwise.Class III:No disturbing deviations in colour allowed.Match errorDefinitionParts to be joined do not match together. This is caused . by mould defect or wrong cooling.Requirements:Classes I, II and III:No errors allowed. Requirement levels are defined by means of reference models.Impuriti

27、esDefinitionImpurities caused by handling, such as dust, grease and fingerprints etc.Inspection is carried out visually.Requirements:Classes I and II:No defects allowed.Class III:Impurities allowed if they do not disturb assembly, use or finishing touch . printing).Remains of loosening materialDefin

28、itionRemains of loosening material appear as shine differences or patches.Inspection carried out visually.Requirements:Class I and II:No defects allowed.Class III:No silicon based materials allowed.Refraction errorDefinitionA distortion or shine caused by distortion or refraction in transparent part

29、. This is caused . by mould defects.Inspection is carried out visually.Requirements:Classes I, II and III:Definition by reference models.Uniformity of outer appearanceDefinitionDeviations from the uniformity of different parts in the same entity. This is caused by :- tooling steel- quality of electr

30、ode- arc machining apparatus- sensitivity of stains from the mould in raw material- injection moulding machineInspection is carried out visually.Requirements:Class I:Deviation from uniformity of outer appearance is not allowed.Class II and IIIAgreed deviations allowed.Wearing of electro eroded surfa

31、cesDefinitionSimilar defects as in items and can be found. Defects can be caused . by wrongly chosen mould raw material or plastic raw material.Inspection is carried out visually.Requirements:Class I:No defects allowed.Class II:Agreed defects allowed.Class III:Defects allowed if they do not disturb assembly or use.