Learn extra approximately Jolly Phonics!

Jolly Phonics is a radical basis for analyzing and writing. It makes use of the artificial phonics method of coaching the letter sounds in a way that is a laugh and multi-sensory. Children learn how to use the letter sounds to study and write words.

Jolly Phonics Intensive Professional Training Seminar is an introductory direction to Synthetic Phonics and is primarily based on the principle of Jolly Phonics, presentation of the letter sounds, preparation and advice on the way to enforce the 5 ideas of the approach, testimonies, characters and certainly, a way to use good phonics class in Singapore on a daily basis in the lecture room placing. Although the route is aimed specifically at preschool and number one instructors, it’s miles for all people who would really like to understand extra about the advantages of the usage of Jolly Phonics, whether or not it’s at school or at home and all people is welcome. Also protected inside the training is particular instruction on the way to use the precise Jolly Phonics resources (songs, books, movements, and many others) and there are numerous beneficial examples of ESL- friendly games, sports and thoughts that may be used each day to train the method. All our customers also receive a Jolly Learning Official Certificate of Attendance and are given the hazard to duplicate beneficial assets onto a pen force. We also provide an online guide for the duration of the year.

Learning letter formation: 

It is very critical that a toddler holds their pencil in an ideal manner. The pencil has to be held inside the ‘tripod’ grip among the thumb and first arms. If an infant’s keep starts off evolved incorrectly, it’s miles very tough to accurate later on. A toddler wishes to shape each letter the ideal way. The letter c is added in the early ranges as this bureaucracy the basic shape of a few other letters, including d. Particular issues to look for are the o (the pencil stroke ought to be anti-clockwise, now not clockwise), d (the pencil starts off evolved inside the center, now not the top), there should be an initial down stroke on letters including m and n. In time an infant will want to analyze joined-up (cursive) writing. It facilitates the fluency of writing and improves spelling. When phrases are written in one motion it’s miles simpler to don’t forget the spelling effectively. Jolly Phonics makes use of the Sassoon Infant typeface which is designed for youngsters getting to know to study and write. Many of the letters (such as d and n) have an ‘exit’ stroke on the quilt to make it less difficult to transfer into joined-up writing.

English training for utmost advantage: 

The secondary level lessons can help your infant complete the school schooling and pass out with flying colors. Through the net portal, you could locate both junior stage and senior stage training centers. It is good to realize that a few institutes even conduct N degree, O level, and A degree examinations. Among all of the topics, language takes a look at is most important. English tuition centre in Serangoon provide teachings for one of a kind languages along with English and Chinese. The training center will provide English fulfillment training at the primary and secondary degree. The popular English paper success instructions in the junior university level are intended for teaching English to the students. If there may be any weak spot in the situation, parents and pupils need to remember more coaching inside the English situation. Certain training centers help college students to excel inside the difficulty and cozy the best grades. If you operate English as your second language, there is each risk that you may not be sturdy in it. To have a super hold at the language, enroll your name within the satisfactory lessons center.

Improve written and oral abilities: 

If you’re weak in English, it implies which you are bad in oral and written capabilities. English tuition center will without a doubt coach you in the correct manner to improve your written and oral abilities. Students, proper from Primary stage to the Secondary stage may also get assistance. In the entire global, English is the maximum widely spoken language and is the high medium of conversation. Composition component is crucial because the pupil has to jot down everything at the paper to talk his/her mind. When you’re taking up English education, you’ll be taught the way to write correct English, frame sentences and use accurate grammar. If you’re weak in oral and written skills, you may appear on line for the exceptional English tuition center.

Make Sure Your Employees Receive Extra Instruction

Business owners need to make certain their own workers are satisfied with their particular work. This will help in a number of ways to make sure staff can work with each other, to ensure tasks are accomplished faster, and to make certain final products are much better. The more content employees are, the much better the company functions. Whenever employers are searching for ways to make the workers more content with their particular job, one of several best approaches to do this will be to supply extra training. This provides a number of advantages as well as could help make sure the staff enjoy their particular work.

One of the primary added benefits is the fact that personnel who get decoupled molding training are likely to know a lot more regarding their particular job and, therefore, will probably fare better at their own work. Added coaching in addition makes certain they will truly feel like a part of the company as well as that they’re essential for the business. A business isn’t going to throw away time or money training a worker they want to eliminate, they will train workers they wish to keep. Staff understand why and thus are frequently delighted whenever they are sought for added education.

After the staff finishes the scientific molding training, they will be far better at their particular career and more competent to work closely with the many other staff. This means the workers can work together for the benefit of the business, however it also signifies the employees could have a much closer working connection. When the employees have a far better working connection as well as get to know one another much better, they’re likely going to be much happier with their particular work. More content workers are likely to stick with their job, not look for a brand-new one. This allows the organization to ensure they’ll have a decreased turn over rate.

In case your company is searching for solutions to improve worker morale and also make certain the workers are pleased with their particular job, injection molding training is going to be an excellent start. Look into the scientific molding seminars that exist right now in order to find the correct one for your staff and also go ahead and sign up. There are too many added benefits to overlook this as well as so much the business can obtain through the additional coaching.

Blown Film Extrusion Introduction

Blown Film Extrusion Introduction
Blown film extrusion is a technology that is the most common method to make plastic films, especially for the packaging industry. The process involves extruding a tube of molten polymer through a die and inflating to several times its initial diameter to form a thin film bubble. This bubble is then collapsed and used as a lay-flat film or can be made into bags. Usually polyethylene is used with this process, and other materials can be used as blends with these polymers. A diagram of a polyethylene chain is shown in Figure 1 to the right.
Background Theory on Polymers

In the cooling step of blown film extrusion, the amorphous, transparent melt crystallizes to form a translucent, hazy, or opaque film. The point where opacity begins in the bubble is known as the frost line. 
Fig 1: Model of polytheylene chain frompolyethylene Wikipedia article.The frost line height is controlled by several parameters: the air flow, film speed, and temperature difference between the film and the surroundings. Properties of the film, such as tensile strength, flexural strength, toughness, and optical properties, drastically change depending on the orientation of the molecules. As the transverse or hoop direction properties increase, the machine or longitudinal direction properties decrease. For instance, if all the molecules were aligned in the machine direction, it would be easy to tear the film in that direction, and very difficult in the transverse direction.

The Film Blowing machine Process

Fig 2: Schematic of set-up from User:J.Chiang.

Typically, blown film extrusion is carried out vertically upwards, however horizontal and downward extrusion processes are now becoming more common. Figure 2 shows a schematic of the set-up for blown film extrusion. This procedure consists of four main steps: The polymer material starts in a pellet form, which are successively compacted and melted to form a continuous, viscous liquid. This molten plastic is then forced, or extruded, through an annular die. Air is injected through a hole in the center of the die, and the pressure causes the extruded melt to expand into a bubble. The air entering the bubble replaces air leaving it, so that even and constant pressure is maintained to ensure uniform thickness of the film. The bubble is pulled continually upwards from the die and a cooling ring blows air onto the film. The film can also be cooled from the inside using internal bubble cooling. This reduces the temperature inside the bubble, while maintaining the bubble diameter. After solidification at the frost line, the film moves into a set of nip rollers which collapse the bubble and flatten it into two flat film layers. The puller rolls pull the film onto windup rollers. The film passes through idler rolls during this process to ensure that there is uniform tension in the film. Between the nip rollers and the windup rollers, the film may pass through a treatment centre, depending on the application. During this stage, the film may be slit to form one or two films, or surface treated. Advantages Blown film generally has a better balance of mechanical properties than cast or extruded films because it is drawn in both the transverse and machine directions. Mechanical properties of the thin film include tensile and flexural strength, and toughness. The nearly uniform properties in both directions allow for maximum toughness in the film.
Blown film extrusion can be used to make one large film, two smaller ones, or tubes that can be made into bags. Also, one die can make many different widths and sizes without significant trimming. This high level of flexibility in the process leads to less scrap material and higher productivity. Blown films also require lower melting temperatures than cast extrusion. Measured at the die opening, the temperature of cast film is about 220 C, where as the temperature of blown film is about 135 C. Furthermore, the cost of the equipment is approximately 50% of a cast line.

Blown Film Extrusion Disadvantages Blown film has a less effective cooling process than flat film. Flat film cooling is done by means of chill rolls or water, which have significantly higher specific heat capacities than the air that is used in the blown film cooling process. The higher specific heat capacity allows the substance to absorb more heat with less change in the substance temperature. Compared to cast film, blown film has a more complicated and less accurate method to control film thickness; cast film has a thickness variation of 1 to 2% versus the 3 to 4% for blown film. The resins used for casting typically have a lower melt flow index, which is the amount of polymer that can be forced through a standard die in 10 minutes according to a standard procedure. The melt flow index for cast film is about 5.0 g/10 min where as for blown film it is about 1.0 g/10 min. Consequently, the production rates for cast film are higher: cast film lines can reach production rates of up to 300m/min where as blown film lines are usually less than half this value. And finally, cast film has better optical properties, including transparency, haze, and gloss.

Common Problems Air entrapment between film layers and rollers – this may cause film scratching or wrinkling, or processing problems when winding up the film due to reduced friction. Possible solutions to this is using a vacuum to remove entrapped air or by using winding rolls with a diamond shaped groove in the rubber cover to increase surface area and decrease amount of entrapped air in the film. Large output fluctuations from the die – this causes thickness variations, and can be prevented by keeping the extruder clean and by using more consistently shaped pellets in the extruder. Melt fractures – these appear as roughness or wavy lines on the film surface, and can be eliminated by lowering the viscosity of the polymer melt. This can be done by increasing the melting temperature or by adding an internal lubricant to the material composition. Thickness variations in the film – this can be avoided by centering the die in the extrusion line before every run, adjusting the air speed of the cooling system, or by using heated die lips. Die lines on the surface of the film – this defect reduces the aesthetic appeal of the film, reduces optical properties, and weakens mechanical properties such as tear strength. This can usually be avoided by routinely cleaning the inner surfaces of the die and by refinishing scratched or roughened flow surfaces. Gels – these defects are small, hard globules encapsulated in the film or stuck on the film surface and reduce the aesthetic appeal of the film and cause stress concentration points which may result in premature failure. These are caused by overheating to the point of polymer degradation in the die, and can therefore be avoided by cleaning the inner surfaces of the die on a regular basis. Optimization of the Process Coextrusion One way to improve the line efficiency of blown film extrusion is to implement coextrusion. This is the process of extruding two or more materials simultaneously through a single die. The orifices in the die are arranged such that the layers merge together before cooling. This process saves time because it extrudes two or more layers at the same time, and it provides a method with fewer steps to produce multilayer films. The production rate for a coextruded multilayer film of three layers is about 65m/min, and the production rate for a single layer of blown film is about 130m/min. Thus, in order to produce 10 000m of a three layer multilayer film, it would take almost 4 hours using a single layer blown film process, and only 2 and a half hours using the coextrusion process. Furthermore, the film produced from the single layer process would require an extra step to glue the layers together using some sort of adhesive. Coextrusion is the least expensive means of producing layered films and the coextrusion system is capable of quick changeovers to minimize production line down time.

Minimizing the Melt Temperature
The efficiency of blown film extrusion can be improved by minimizing the temperature of the polymer melt. Reduction of the melt temperature causes the melt to require less heating in the extruder. Normal extrusion conditions have a melting temperature at about 190 C despite the fact that the temperature of the melt only needs to be about 135 C. However, it is not always practical to decrease the melting temperature by that much. By decreasing the melt temperature 2 to 20 C, the motor load can be decreased by about 1 to 10%. Furthermore, reduction of the melt temperature causes less need for cooling, so there is a reduced use of the cooling system. Moreover, removing heat from the bubble is usually the rate-limiting factor in this extrusion process, so by having less heat in the polymer to remove, the rate of the process can be increased, thus yielding higher productivity. A way to maintain the melt temperature at a minimum is to choose an extruder that is matched to the specific processing conditions, such as the material of the melt, pressure, and throughput.

Heated Extrusion Die Lips
Typically, solutions to melt fractures involve decreasing the output or increasing the melt temperature to decrease the shear stress in the extruder. Both of these methods are not ideal because they both reduce the efficiency of the blown film line. Heated extrusion die lips can solve this problem. This targeted heating method allows for film extruders to be run at higher production rates with narrower die gaps while eliminating melt fractures. Direct heat is applied to the surface of the polymer melt as it exits the die so that viscosity is reduced. Therefore, melt fractures, which are caused when trying to extrude too much of the polymer at one time, will no longer act as a limiting factor to increasing the production rate. Furthermore, heated die lips use less energy than increasing the melting temperature because only the surface of the melt is heated and not the bulk of the liquid. Another benefit of using heated die lips is that thickness variations can be controlled by adding heat to certain areas along the die circumference to make the film at that position thinner. This would ensure that no excess material is used.
Determine how much energy each of these processes can save per given volume of material. 

Above article from www.appropedia.org

Kingdom Machine Co.,ltd Ruian Economic Zone,Wenzhou,China 325200
Mobile:0086-13958812663;  0086-13088651008
Tel.:0086-577-65127709       Fax:0086-577-56846789 Whatsapp:0086-13958812663
sale@kingdommachine.com www.kingdommachine.com www.chinablownfilmextrusion.com