GLASS CONTAINER DEFECTSAND THEIR CAUSES AND REMEDIESThe Examination of a ContainerA good container is a container that will go through thecustomers filling line without causing any difficulty and willcarry his product to the consumer.It is, therefore, essential that before a container is released forsale from the glass plant, it successfully passes on inspectionwith standards set to meet the customers needs.There are approximately one hundred defects which candevelop in the container during the production process, somebeyond the control of the operator, for example stones; but byfar the largest number occur either in the feeder or machineoperation.It is important that all production personnel learn to recognizethe defects and understand what remedies to use in order toeliminate them.hen a glass container fails on the customers filling linebecause of a manufacturing defect, the reputation of glasssuffers, which results in a loss of customer good!will. Alwaysremember; "The #rice of a $uality %ontainer is &ternal'igilance."(emedies offered hopefully give you a basic understanding ofdefects and their causes. In some instances, several remediesmay be needed to correct the causes.The Various Parts of a ContainerIn order to identify defects in a container, it is most useful to )now all the various types and parts of the containerTypes of Containers*A((+ *&%, I-& .+/T0 T1#&Parts of a ContainerThe FinishThis is the top of the container above the nec) ring parting line. It includes2 The 3ealing 3urface, 4ore, 4ead or %ollarThe 3ealing device is in the finish 5see next section6, also the bore or mouth for filling and emptying. The bead or collar is used to assist in transferring the parison into the blow mold.The NeckThe part which extends from the parting line to the curve at the base of the nec).The ShoulderThis extends from the base of the nec) to the straight part of the body.The BodyThe main part of the container which holds the product.The BottomThe part of the container on which it stands when upright.InsweepThe curve between body and bottom which helps to improve glass distribution and thus strength. Push!pThe center of the bottom which is raised up to provide a flat surface on the outer edge of the bottom and thus provide a firm seating.hen producing a glass container, various items of mold e7uipment are used as follows2 4lan) .old, 4affle, #lunger, *ec) (ing, 4low .old and 4ottom #late. here these individual items 8oin, seams are produced in the container. If the seams do not meet the standard specified, then the container is re8ected. It is, therefore, essential that all mold e7uipment be examined in the mold shop and again in the #roduction -epartment. It must also be stored correctly and handled with care at all times.Neck "in# Partin# $inehere the nec) ring and the blan) mold 8oin, there is a seam.Blank SeamThe blan) mold is in two parts. It closes around the nec) ring and then receives the hot gob of glass. here the two halves of the blan) mold 8oin, there is a seam, which can sometimes be seen as a wavy line on the finished container.Baffle %arkThe baffle sits on top of the blan) when counterblow ta)es place to form the parison. If there is a bad match between blan) mold and baffle, then a baffle mar) or seam may be seen in the container bottom.%old SeamThe blow mold action is the same as the blan) except that is closes around the bottom plate. here the two halves 8oin, there is a mold seam, which runs vertically on the whole length of the container.Bottom Plate Partin# $inehere the blow mold and bottom plate 8oin there is a seam.Su##estions for "emedyin# Container &efectsIt is essential that the machine operator be able to identify defects 7uic)ly and accurately, and to )now how to remedy them. .a8or defects have been listed, with an accurate description and a s)etch indicating the appearance of the defect and the position in the container where it ismost commonly found. The causes and remedies for each defect are also listed.The operator should fre7uently examine the containers passing along the conveyor from machine to stac)er. Approximately once every twenty minutes, but depending on production speed, one container from each mold should be set out and allowed to cool so that it can be handled andthus examined more closely for defects. -ont waste these containers if they are not faulty and have not been damaged!put them into the lehr.4efore correcting a defect, always remember the following29. 0ow many of the particular defects are re8ects:;. If corrected, what other types of defects may be produced as a result of the ad8ustment made:lass too cold 20%achine Setup and )peration *ec) ring closing too soon when reverting pinching the finish Insufficient or une7ual nec) ring opening Incorrect cushioning of invert mechanism on the blow mold side *ec) ring opening too hard Incorrect setting of blowhead 5out of center6 &nd of outstro)e cushioning on ta)e!out incorrect Ta)e!out tongs are out of line or closing too hard Incorrect setting of nec) ring over the mold 4ottom plate too high 30%old E4uipment 4ottom plate too tight in mold recess 5resulting in mold opening too hard6 3houlder radius too sharp 5for odd shape bottles6 causing bottles to roc) on bottom pate resulting in damage form ta)e!out fingers 50Inspection E4uipment Incorrect operation of gauging e7uipmentREMEDIES: 10Feeder Ad8ust the feeder temperature20%achine Setup and )peration (etard nec) ring closing Increase nec) ring opening Ad8ust cushioning of invert mechanism Ad8ust nec) ring opening for smoother action Ad8ust blow head over blow mold Ad8ust outstro)e cushioning of invert mechanism Ad8ust ta)e!out tongs, allowing them to close slower 3et nec) ring over blow mold to nec) ring setting gauge %orrect the bottom plate mechanism setting30%old E4uipment %hec) e7uipment against mold gauges &nsure shoulder radius has some relief50Inspection E4uipment %orrect timing of gauging e7uipment 5cold end inspection6 NEC( "IN, SE+%A fin or seam of glass lying across the top or the side of the finish.

"A+S$S,10Feeder >lass too hot 20%achine Setup and )peration *ec) ring not closing properly because of carbon accumulation or glass in ring =inish and loc)ing thimble not engaging correctly in the guide ring #lunger up pressure too high 5press and blow6 4lan) closing pressure too low 5press and blow6 4land supporting mechanism worn ear on mold opening and closing mechanism lin)age Improper timing of the machine 30%old E4uipment 4lan) mold recess for nec) ring too large or nec) ring diameter too small *ec) ring, finish guide ring or finish thimble worn or dirty or out of dimension Interference between tongue and groove of nec) ring 4lan) volume too small for glass weight and plunger size 5press and blow process6 -$M$&I$S:10Feeder Ad8ust feeder temperature 20%achine Setup and )peration %hange nec) ring %hange thimble and?or ad8ust height of plunger mechanism (educe pressing pressure %hec) blan) closing pressure %hange blan) supporting mechanism lin)age %hange lin)age on blan) closing mechansim 30%old E4uipment %hec) against gauges (enew nec) ring.*$". &$#$"TS SE+% )N NEC( "IN, P+"TIN, $INEA seam which has a fin of glass around the parting line between the finish and the nec) of the container. 10 %achine Setup and )peration -irt prevents the blan) mold from completely closing *ec) ring and plunger are dirty 20%old E4uipment *ec) ring diameter is too small for the bland mold 4lan) mold dovetail too large for the nec) ring *ec) rings are not correct matched"E%E&IES-10 %achine Setup and )peration %hange the dirty mold e7uipment %hange all dirty nec) rings and plungers;.%old E4uipment / Increase the neck ring diameter./ "hange neck rings for a correctl( matched pair. BENT NEC(A nec) where the finish is tilted to one side.CAUSES:10 Feeder >ob temperature too high20 %achine Setup and )peration .old is running too hot, causing the container to be pulled to one side .achine speed too high 4low head not setting properly over the molds Ta)e!out operating too fast and swinging bottle Incorrect counterblow pressure and time of application. *ec) rings not relieving correctly 4ottle blowing time too short Ta)e!out tongs are out of line *ec) ring is running hot30 %old E4uipment Incorrect plunger design 5blow and blow6 4low head not deep enough Ta)e!out tongs out of shape"E%E&IES-10 Feeder Ad8ust gob temperature 20%achine Setup and )peration Increase the cooling wind (educe the machine speed Ad8ust blow head setting on the mold Ad8ust the ta)e!out height and ad8ust the cushioning Increase the counterblow time and?or pressure Ad8ust blan) and mold cycle 3horten plunger contact time Increase blan) contact time Increase reheat and mold contact time %hange to a larger exhaust hole on blow head30%old E4uipment %orrect plunger design %hec) the depth of the blow head cavity and correct if necessary (eplace the ta)e!out tongs Note- It can cause trou6le on the fillin# line and should 6e corrected at once0&I"T* NEC(A nec) which has a dirty or scaly appearance."A+S$S,10%achine Setup and )peration Too much cooling on the blan) mold 4uildup of carbon on nec) of the blan) due to excessive swabbing -irty swab 3wabbing compound too thic) 3wab made of incorrect material and wrong shape rong grade of mold lubricant &xcessive oil on the delivery e7uipment20%old E4uipment #oor surface of blan) cavity -$M$&I$S:10%achine Setup and )peration (educe the blan) cooling %hange blan) /se a new clean swab of correct shape /se a correct grade swabbing compound /se a swab made form cotton /se correct grade of mold lubricant =it drip plan to deflector 20%old E4uipment Improve polish on mold e7uipment surfaces SH0+L&$- &$#$"TSS')!$&E" C'EC(S3urface crac)s on the shoulder of the containers. They are usually wavy in appearance.C+!SES-10 Feeder Incorrect glass temperature!can be either too hot or too cold.20 %achine Setup and )peration 4ottom plate is set too high or too low, causing drag on bottle shoulder when mold is opening .old is running too hot, causing the bottle to stic) to the mold .old holders are worn, causing the mold to drag on the bottom plate when opening Too much final blow pressure blowing the bottle up too hard against the mold. 5=inal blow pressure should be regulated to be sufficient to )eep the bottle in shape6.30 %old E4uipment .old not sufficiently relieved on bottom plate, causing bottle to drag on mold when mold is opened =lat shoulder container with insufficient relief on shoulder Incorrect positioning of parting line 5add shaper containersREMEDIES:10 Feeder 3et feeder at correct temperature20 %achine Setup and )peration @ower or raise bottom plate mechanism Apply more cooling wind to mold %hange mold holders. %hec) the old mold holders against repair dimensions (educe final blow pressure Ad8ust cooling wind application %hec) and ad8ust blow head timing (aise the height of ta)e!out tong heads30 %old E4uipment Improve relieve on bottom plate &nsure relief on mold shoulder &nsure correct positioning of parting line in mold10 Feeder /neven gob temperature >ob too long20 %achine Setup and )peration >lass is improperly loaded 5off center6 4lan) mold not properly swabbed =inal blow ta)es place too late, allowing excessive run of parison 4lan) mold too hot 30 %old E4uipment Incorrect blan) design =unnel size incorrectREMEDIES:10 Feeder Ad8ust forehearth temperature so that gob does not curl 3horten the gob20 %achine Setup and )peration Ad8ust deflector to center of blan)!chec) size of deflector 3wab blan)s more fre7uently Advance final blow Ad8ust blan) cooling 30 %old E4uipment %hec) for correct blan) design %hec) funnel size BODY DEFECTSB$+N( +N& B$)7 %)$& SE+%S3eams which are relatively large, extending from the shoulder to the bottom of the container. 4lan) seams tend to veer off from the mold seam."A+S$S:10 Feeder >lass too cold, causing difficult pressing on AB;A operation when producing lightweight ware ortall 8obs li)e mil) bottles >lass too hot >ob weight too heavy 5B; process620 %achine Setup and )peration ear on blan) and mold holders ear on blan) and mold lin)age Incorrect blan) and blow mold lin)age alignment Incomplete stro)e of blan) and blow mold piston in cylinder .isalignment of plunger mechanism %arbon deposit on blan) and blow mold halves >lass in interloc)ing fit or blan) or blow mold Interference between blan) and?or blow mold with bloc) loc) at operation temperature #lunger mechanism too high &xcessive plunger and counterblow pressure *ec) ring incorrectly set 4ottom plate running too hot 4lan) mold too hot 4affle too hot30%old E4uipment (ecess on blan) and mold for either plunger or bloc) loc) location incorrectly made or too tight fit Interference between nec) ring and blan) mold nec) ring diameter too large /nsuitable pressing gate on parison design 5press and blow6 4lan) and molds insufficiently hollow scraped ! insufficient relief or interloc)ing fits and for tongue and groove fits 4lan) and mold warped and?or worn out 4ottom plate holding blow mold open Incorrect selection of bottom plate size REMEDIES:10 Feeder Ad8ust gob temperature %hec) gob weight20 %achine Setup and )peration %hange mold holders and chec) the old ones against repair dimensions %hec) blan) and mold supporting for wear %hec) with mold and blan) lin)age aligning fixture (ealign the plunger mechanism %hange mold and blan) %lean the mold and blow out the glass %hec) bloc) loc) fitting at operating temperature for tightness Ad8ust plunger mechanism height (educe counterblow pressure %hec) invert mechanism with nec) ring mechanism aligning fixture Apply cooling to bottom plate Increase the cooling on blan)