Plastic bags do not pay attention to a little, bag sealing cooperation with will be affected

1, heat sealing temperature, heat sealing temperature of the composite membrane and the choice of the function of the composite base material, thickness, the type of bag making machine, there is a close relationship between speed, air pressure, etc, which directly affect the heat sealing strength of concave and convex. Composite membrane material of the sealing temperature is by heat sealing sticky flow temperature or melting temperature, heat sealing temperature high temperature cannot exceed the decomposition temperature of the heat sealing materials. Sticky flow between temperature and decomposition temperature the temperature of the heat sealing temperature range for the heat sealing materials, it is a key element to affect the quality and control the heat sealing. The heat sealing temperature range, the greater the heat sealing function, the better, the quality control is more simple, more stable. Colleagues composite film heat sealing temperature not higher than the printing substrate of heat setting temperature. Or it will cause heat sealing parts of the contract, wrinkling, lower the heat seal strength and impact resistant function of the bag. Printing substrate temperature resistance good, such as the BOPET, BOPA etc. , improve heat sealing temperature can improve yield rate; Printing substrate temperature resistance is poor, such as BOPP as far as possible choose low heat sealing temperature, and after increasing pressure, choice of fruit drop speed or low temperature heat sealing materials to ensure that the heat seal strength. 2, heat sealing pressure air supply by a bag making machine pressure spring. The size of the heat sealing pressure and the performance of the composite film width, thickness, heat sealing and so on. Polarity heat sealing materials have higher activation function, temperature falling on its viscosity is bigger, so the heat sealing pressure is small, prevent heat sealing parts out of the molten material, heat sealing effect. Nonpolar and PE, PP material, the activation function, the required pressure is higher, is good for heat sealing strength, interface sealing. Heat sealing pressure should follow increases with increasing the thickness of the composite membrane. Jorge lack of sealing pressure, two film heat-seal hard, difficult to exhaust all caught in the bubbles in the weld center, Heat sealing pressure is too high, will squeeze out the molten material, welding edge, cause increased. Accounting heat sealing pressure, want to consider the width of the required heat sealing rods and practice area. Heat sealing bar width is wider, the greater the pressure. Heat sealing bar width is too wide, easy to make the heat sealing part GaCang bubble, it is difficult to heat sealing healthy and vigorous, generally can choose hollow out heat sealing bar, whether in a strengthening heat sealing fastness. The same width of heat sealing bar, if the surface carved, slashed its practice touch area, pressure per unit area increases accordingly, this is good for the packing bag of heat sealing width is larger. 3, heat sealing speed heat sealing bag making machine to produce power, also is the important factor affecting the heat seal strength and appearance. The faster the heat sealing, marching to the corresponding heat sealing temperature, to ensure that the intensity of heat sealing and heat sealing situation arrived at the best value; In the same heat sealing temperature and pressure, heat sealing the slower speed, heat sealing material of fusion will more fully and more healthy and vigorous, but it can't cause increased phenomenon. Domestic production of bag making machine, heat sealing time length is mainly by the choice of bag making machine speed. Increase heat sealing time, it is necessary to drop bag making speed, fall from power. Selection is independent of variable frequency motor control heat sealing bar lifting and conveying, independent adjust heat sealing time, without changes to the bag making speed, will greatly facilitate the operation of the bag making machine and quality control. 4, cooling, cooling process is under the pressure of must use low temperature to finalize the design just melt sealing weld, eliminating stress, have gathered to cut weld shortened, the appearance of the travel bag flatness, the process of moving heat sealing strength. Bag making machine of the cooling water is generally tap water or about 20 ℃ circulating water. High water temperature, cooling pressure no bar, no such as cooling water circulation, circulation can lead to poor cooling, heat sealing strength decreased. Number 5, heat sealing, most the both longitudinal and transverse heat sealing bag making machine with hot plate welding method, the longitudinal heat sealing number depends on the useful heat sealing bar length and the ratio of the bag length, lateral heat sealing number by the number of sets of the machine heat sealing device of choice. Good heat sealing general requirements heat sealing number in more than 2 times. Most lateral heat sealing equipment for three groups. In order to satisfy the requirement of the broad-brimmed heat sealing, tend to increase the lateral heat sealing equipment, increase the number of heat sealing, drops to heat sealing temperature, reduce the necking phenomenon. A longer on the packing bag of specification, can choose multiple feeding skills, make each feed length to bag a long half or a third, then increase the number of heat sealing, improve heat sealing effect, but will decline from power, so some bag making machine to increase the length of the longitudinal heat sealing bar, to increase the number of heat sealing, to ensure the quality of heat sealing. 6, heat sealing bar space heat sealing bar space refers to the heat sealing bar touch the floor, scheduled air pressure to the heat sealing pressure on the surface of the interval. In the same film thickness, heat sealing speed, heat sealing bar space is small, heat sealing time is relatively small, the product of heat sealing strength will drop. The general heat sealing bar space set at 1. 0 to 1. 5 mm, with thin film thickness, transfer function, bag making speed and so on.