復合袋包裝袋破袋率如此高的源頭
1、熱封溫度對熱封強度的影響為直接。
1. The effect of heat sealing temperature on heat sealing strength is direct.
各種材料的熔融溫度的高低,直接決定復合袋的低熱封溫度。生產(chǎn)過程中,由于熱封壓力,制袋速度以及復合基材的厚度等多方面影響,實際采用的熱封溫度往往要高于熱封材料的熔融溫度。
The melting temperature of various materials directly determines the low heat sealing temperature of composite bags. During the production process, due to various factors such as heat sealing pressure, bag making speed, and the thickness of the composite substrate, the actual heat sealing temperature used is often higher than the melting temperature of the heat sealing material.
熱封的壓力越小,要求熱封溫度越高;機速越快,復合膜的面層材料越厚,要求的熱封溫度也越高。熱封溫度若低于熱封材料的軟化點,則無論怎樣加大壓力或延長熱封時間,均不可能使熱封層真正封合。
The lower the pressure of the heat seal, the higher the required heat seal temperature; The faster the machine speed, the thicker the surface material of the composite film, and the higher the required heat sealing temperature. If the heat sealing temperature is lower than the softening point of the heat sealing material, no matter how much pressure is increased or the heat sealing time is extended, it is impossible to truly seal the heat sealing layer.
但是若熱封溫度過高,又易損傷焊邊處的熱封材料熔融擠出,產(chǎn)生“根切”現(xiàn)象,大大降低封口的熱封強度和袋子的耐沖擊性能。
However, if the heat sealing temperature is too high, it is easy to damage the heat sealing material at the welding edge by melting and extrusion, resulting in a "root cutting" phenomenon, greatly reducing the heat sealing strength of the seal and the impact resistance of the bag.
2、熱封層材料的種類、厚度以及質量對熱封強度有決定性的影響。
2. The type, thickness, and quality of the heat sealing layer material have a decisive impact on the heat sealing strength.
一般
濟南復合塑料袋常用的熱封材料有CPE、CPP、EVA、熱熔膠以及其它一些離子型樹脂共擠或共混改性薄膜。熱封層材料的厚度一般在20~80μm之間,特殊情況下也有達100~200μm的。同一種熱封材料,其熱封強度隨熱封厚度的增大而增大。蒸煮袋的熱封強度一般要求達40~50牛頓,因此,其熱封材料厚度應在60~80μm以上。
Generally, the commonly used heat sealing materials for Jinan composite plastic bags are CPE, CPP, EVA, Hot-melt adhesive and other ion-exchange or blend modified films. The thickness of the heat sealing layer material is generally between 20 and 80 μ Between m, it can also reach 100-200 under special circumstances μ M's. The heat sealing strength of the same heat sealing material increases with the increase of heat sealing thickness. The heat sealing strength of steaming and boiling bags is generally required to reach 40-50 Newton, therefore, the thickness of the heat sealing material should be between 60-80 Newton μ Above m
3、要達到理想的熱封強度,一定的壓力必不可少。
3. To achieve the ideal heat sealing strength, a certain amount of pressure is essential.
對于輕薄包裝袋,熱封壓力少要達到2kg/cm2,而且隨著復合膜總厚度的增加而相應提高。若熱封壓力不足,兩層薄膜之間難以達到真正地熔合,致合局部熱封不好,或者難以趕盡夾在焊縫中間的氣泡,造成虛焊;當然,熱封壓力也不是越大越好,應以不損傷焊邊為宜,因為在較高的熱封溫度時,焊邊的熱封材料已處于半熔融狀態(tài),太大的壓力易擠走部分熱封料,使焊縫邊緣形成半切斷狀態(tài),焊縫發(fā)脆,熱封強度降低。
For lightweight packaging bags, the heat sealing pressure must reach at least 2kg/cm2, and it will increase correspondingly with the increase of the total thickness of the composite film. If the heat sealing pressure is insufficient, it is difficult to achieve true fusion between the two thin films, resulting in poor local heat sealing or difficulty in removing bubbles trapped in the middle of the weld seam, resulting in false soldering; Of course, the higher the heat sealing pressure, the better. It is advisable not to damage the welding edge, because at higher heat sealing temperatures, the heat sealing material of the welding edge is already in a semi molten state. Excessive pressure can easily squeeze out some of the heat sealing material, causing the weld edge to form a semi cut state, causing the weld to become brittle and the heat sealing strength to decrease.
4、熱封后的焊縫若冷卻不好,不但會影響焊縫的外觀平整度,而且對熱封強度有一定的影響。
4. If the cooling of the weld seam after heat sealing is not good, it will not only affect the appearance flatness of the weld seam, but also have a certain impact on the heat sealing strength.
冷卻過程就是通過在一定的壓力下,用較低的溫度對剛剛熔融熱封后的焊縫進行定形,應力集中的過程。因此,壓力不夠,冷卻水循環(huán)不暢,循環(huán)量不夠,水溫太高,或冷卻不及時都會致使冷卻不良,熱封邊起翹,熱封強度降低。
The cooling process is the process of shaping the weld seam that has just been melted and heat sealed at a lower temperature under a certain pressure to eliminate stress concentration. Therefore, insufficient pressure, poor circulation of cooling water, insufficient circulation volume, high water temperature, or untimely cooling can lead to poor cooling, warping of hot sealing edges, and reduced strength of hot sealing.
The source of such high bag breakage rate in composite bag packaging can be found from the above four aspects. We hope to provide you with good help. For more information, please come to our website http://www.ssxx10.com Consult!