Making zipper bag necessary, you also need to have a!
Packaging is the most important function is to protect the quality of all products, also is said to make the product in the process of storage, transport and sale of the entire flow, through the different links, in a different environment, are not damaged, lost, leakage and metamorphosis.
This request in the process of bag sealing necessary must strength and sealing function, can withstand the weight must be the pressure of the contents, ensure that the product in the process of circulation is not crack, leakage, reach the purpose of protection products.
And the bag is to users before a final production working procedure, quality control is more important.
One, the material selection 1.
With non heat sealing material for the surface material, should consider to choose good heat resistance, thermal deformation of small material, such as BOPA, BOPET, BOPP, paper, etc.
Lining material namely, heat sealing material, the surface material low thermal deformation temperature 30 ℃ can be heat sealing advisable, assume that the surface material and heat sealing layer of thermal deformation temperature difference is too small, will bring bag making temperature control is difficult, because the temperature is low, the sealing fastness is poor, can not meet the requirements, in order to trek the sealing fastness, will the temperature rise, because the table material thermal deformation temperature difference is too small, a brief to burnt surface materials.
On the same kind of heat sealing material, the heat sealing strength will follow heat sealing material thickness increases.
So back sealing bag, self-reliance bag its lining material in 30 & mu;
M thickness above, it is advisable to assume that the inner material is too thin, will affect the sealing bag products.
Zipper should choose heat sealing zipper sealing strip temperature is low, general with lower than the lining materials can be heat sealing temperature 5 ~ 10 ℃ is preferred, such as the city into the PE L - packaging materials co. , LTD
Article 101 zipper sealing heat sealing temperature than the LL - PE
201 low around 10 ℃ for different PE bag lining material selection, to reach and lining material bounding the best condition.
Second, in front of the bag ready to 1.
Ensure composite membrane composite layer solidify completely, otherwise easy cause after bag heat sealing edge deformation, affect the appearance of the bag;
Choose appropriate heat seal as required, and tidy up clean, ensure that heat sealing knife with smooth surface, check whether the insulation cloth shape, smooth;
Check the bag making machine parts, according to the experience (
See previous such data yield condition)
The preset pressure sealing temperature, preheating, arrived at the preset temperature 20 minutes rear can put into produce.
Need to pay attention to reach the preset temperature does not indicate the heat seal has arrived in the preset temperature, should be a process of heat conduction to achieve balance;
Bag making process conditions of adjustment of temperature, pressure, time,
Heat sealing is not short of three elements, is the main condition of the process parameters, temperature, pressure, time,
Need to take care of each other to adjust, so as to achieve the best condition.
Three, heat sealing temperature heat sealing temperature effect on the heat sealing strength most directly, it is the main basis that choosing the best temperature viscous flow condition.
Heat sealing temperature should be according to the thickness of composite materials, and processing speed, etc.
In the process of produce practice, because by heat sealing pressure, bag making speed and the thickness of the composite base material, the influence of various elements such as heat sealing temperature tend to be higher than the melting temperature of the heat sealing materials.
If the heat sealing temperature below the melting temperature of the heat sealing materials, even if the increased pressure and heat sealing time, can make the heat sealing layer real sealing;
Jorge sealing temperature is too high, and a brief harm pincer-like device heat sealing materials, greatly reduced the sealing strength.
Four general conditions, sealing pressure, pressure were the first to adjust the selected parameters, general equipment pressure value, with heat sealing blade pressure side about 3 mm advisable, pressure balance,
Around or before and after)
Is very important, lack of tightening starts to form pressure, make thermal cover difficult to real fusion together, cause heat sealing not firm, sometimes also can produce phenomena of the bubbles out of weld unclean.
Excessive tightening will constitute the pressure is too great, will cause heat seal and traction are not synchronized, and in the heat sealing at high temperature, pincer-like device materials are already in a molten condition, if pressure is too large, short squeezes out part of the heat sealing material, make the sealing edge half block status, cause pincer-like device materials thin, crisp, heat sealing strength decreased.
Five, sealing time (
Sealing time not only affect the heat sealing strength and also will affect the appearance of the composite bags flatness.
When heat sealing temperature and heat sealing pressure on, the longer the heat sealing time, heat sealing layer fusion more fully, combined with a more healthy and vigorous, sealing strength is high, but assumes that heat sealing time is too long, thin film is easy to shorten, brief pincer-like device wrinkling, influence smoothness appearance.
Six, by using low temperature cooling process is to finalize the design just after melting heat sealing weld.
Cooling temperature should be at the lowest temperature condensate with cooling knife is not advisable, cooling water circulation dredging, assumes that there is no condition using the cooling water, should try to trek water flow, to ensure that the cooling effect.
Not assume that the sealing side of cooling after hot sealing, finalize the design lacks, cannot eliminate the internal stress, will affect the heat seal strength and appearance.
Heat sealing number, heat sealing heat sealing strength is higher, the more general requirements heat sealing number for at least two more times.
Longitudinal heat sealing number depends on the longitudinal heat sealing knife useful length and the ratio of the bag length;
Lateral heat sealing number by the number of sets of lateral heat sealing bag making machine equipment selection.
Eight, the process control in the process of produce should be constantly to check the quality of the finished product, in addition to the view of vision standards, appearance, but also for the sealing strength and sealing function view.
Found that the problem timely adjustment, and make detailed records.