Category Archives: Industrial Equipment

PP Hollow Sheet Extrusion Line Manufacturer – Leader Extrusion Machinery

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Leader Extrusion Machinery Company is the professional extruder machine manufacturer in the industry.

 

Leader Extrusion Machinery has more than 20 years’ experience designing and manufacturing plastic extrusion machinery. They are specializing in manufacturing of PP, PS, PVC, PC sheet extrusion lines and PP, PC PET hollow profile sheet extrusion lines.

 

To assure high quality and high precision products Leader Extrusion Machinery Company is equipped with sophisticated high tech production machinery and equipment. Furthermore, with the improvement of technology, plastic extrusion film and sheets have become everyday products. With lightweight, waterproof, durable and environmental features applications are unlimited!

 

Below, I will present you Leader Extrusion Machinery’s PP hollow sheet extrusion line.

 

Plastic Hollow Profile Sheet Extruder

PP Hollow Profile Sheet Extrusion Production Line

pp hollow sheet extrusion line

 

PP Hollow Sheet Extrusion Line is lightweight, impact and oil resistant, and waterproof. Applications include packaging containers, display panels, daily use items, stationery, and protective packaging for building materials. PP can be formed into any shape and type of product such as turnover boxes, component boxes and plastic partitions. This is excellent material widely used for protecting electronic parts.

 

If you want to get more specification about this PP hollow sheet extrusion line, please do not hesitate to check out the website of Leader Extrusion Machinery. You also can find a variety of extruder machines on their product catalog.

 

 

Leader Extrusion Machinery Ind. Co., Ltd.

No.235, Sec.1, Gangbu Rd., Wuqi Dist., Taichung City 43546, Taiwan.

Tel: 886-4-2638-0888

Fax: 886-4-2638-0333

E-mail: leadertw.ex@leadertw.com

The Advantage of Using CNC Surface Grinder in Auto Parts Processing

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Auto parts (auto spare parts) constitute the overall car of each unit and in the   service of automobile products. Auto part usually requires high precision and high reliability. Manufacturing of auto bearing parts with CNC surface grinder could gain the following advantages:

 

  1. High Precision: two parallel plane, through the disc, the swing arm type feeding NC vertical double end face grinding machine grinding, the precision of the products can reach 0.002 ~ 0.003 mm.

 

  1. High stiffness is the difference between two sides of the plane can control within 0.006 mm dimension consistency control ability.

 

  1. High Efficiency: disc, the swing arm type feeding CNC grinding machine, compared to its efficiency on the basis of the same precision grinding machine is more than 10 times.

 

  1. For many applications, grinding is the preferred process strictly because of the finish it provides. These machines handle the tight tolerances of tenths or millionths without a struggle. Extremely stable machines, they’re made for dealing with super tight tolerances.

 

  1. Temperature changes in and around a machine can create steady fluctuations in component sizes. Although these variations may seem minute, when tolerances are in tenths and millionths, they can spell the difference between a good part and scrap.

 

  1. Easy to Operate: vertical double end face grinding machine, CNC control convenient operation convenient operation compared with horizontal double end face grinding machine fixture design more reasonable, more scientific and more flexible.

 

  1. For successful hard turning, the key components for a machine are that it is rigid, thermally stable, the more can be integrated into the process and the more efficient the operation.

 

  1. Along with vibration stress release, these outstanding structural features assure high strength, maximum damping capability, and longer service life.

 

Just as streamline, CNC surface grinding machine is another very important   revolution in auto parts manufacturing. With these machines, manufactures can   produce both normal and special auto parts in large amount. That shorts the whole design and manufacturing processing of an auto part and also lowers the cost.

 

If you need more information about CNC surface grinders, I recommend a company to you – that’s Tong Yi Machinery Inc.

 

From manual shaping grinding machine, semi-automatic grinding machine, the full-automatic grinding machine of three axes, NC level grinding machine, NC level rotary grinding machine, any product was all researched and developed and designed high-accuracy towards pluralism and humanization, believe that can offer more perfect quality service for every customer. Get more details, please feel free to contact with Tong Yi Machinery.

 

Article Source: Quora

How A Manual Chain Hoist Works?

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From What Parts A Manual Chain Hoist Consists

Manual chain hoist is a pretty simple device considering the large amount of weight such a tool can lift. Chain hoists are made from durable, high grade steel to ensure safety and reliability when lifting couple of tons heavy loads. Manual chain hoist can be separated in three different part categories: lifting chains, lifting mechanism and hooks.

 

Chain hoist has got two chain loops – hand chain and lifting chain. Hand chain sits on a wheel located in the lifting mechanism; it needs to be pulled by hand in order to lift a load. The wheel inside the lifting mechanism has got special pockets that allow the hand chain to move the wheel. Lifting chain also loops the lifting mechanism and lifts or lowers a load. At the end of the chain there is a grab hook, where you can attach lifting chains or slings, a load leveler or load itself. There is also a hook on the top of the chain hoists housing. This hook is used to attach the hoist to a ceiling mount, trolley system or other construction that can withstand the weight a hoist will lift. Most chain hoists have swivel hooks, meaning that they can be turned 360 degrees around to allow for easier mounting. The lifting mechanism consists of a cog, axle, drive shaft, gears and sprockets. There is also a chain stopper or brake on most chain hoists that prevents load from lowering under a load.

 

How A Manual Chain Hoist Works

The physics behind a chain hoist are very simple and have been used for lifting heavy objects for a long time. Chain hoist uses a mechanical advantage to transform small force over a long distance to large force over a short distance; this is possible by using multiple larger and smaller gears in the chain hoist mechanism.

 

To lift a load, chain hoist operator needs to pull down the hand chain; this turns the cog and axle which goes through the lifting mechanism. Inside the lifting mechanism are multiple gears which increase the mechanical work applied when pulling the hand chain for dozen times using gear ratio, allowing to easily lift loads with multiple ton capacity.

 

So when the hand chain is pulled, the cog which is rotated by the hand chain turns the drive shaft and gears which turn the load chain sprocket, this also rotates the load chain that is looped over the load chain sprocket and lifts a load. Larger gears move slower than smaller gears, but create more force; this is why chain hoist lifts load very slowly when compared to a hydraulic hoist. At the end of the lifting chain is a grab hook, which allows easily attaching and detaching a load. Also, most chain hoist lifting mechanisms have a ratchet or braking system that prevents the load from slipping back, but allows lowering a load by pulling the other side of the hand chain.

 

Manual Chain Hoist In Comparison With Other Hoist Types for Engine Lift

Chain hoists have different uses, for example in construction sites, shops, warehouses, also in car service stations and other application, where precise lifting is required.

 

The Disadvantages Of Manual Chain Hoists For Engine Lifting Are:

 

  • They are slower than other type of hoists;
  • They have special requirements for installation areas, which limit places these hoists can be used, in opposite hydraulic hoists just need a solid and level ground.

 

However, There Are Also Some Advantages For Using Manual Chain Hoists For Engine Lifting:

 

  • They don’t need electricity, oil or other additional resources to work;
  • They are cheaper than electric or hydraulic hoists;
  • They are simple to use and easy to repair and maintain.

 

If you need more information about manual chain hoists, try to visit Cheng Day Machinery Works Co., Ltd. – the company specializes in producing wire rope hoist, electric chain hoist, crane components, chain hoist trolley, etc. Get more details please send inquiry or contact with Cheng Day Machinery.

 

 

Article Source: http://www.knockoutengine.com/how-a-manual-chain-hoist-works/

Transformer Winding Machines: Significance and Types

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Transformer is one of the most crucial components of any electrical circuit. A transformer is basically used to convert (increase or decrease) the voltage, depending upon the maximum allowable voltage of an application. Thus, there are two main types of transformers, namely, step-up and step-down transformers. The main difference between these two types of transformers is the number of windings. Thus, winding becomes the most important part of this electrical device. These windings are manufactured with the help of transformer winding machines.

 

Transformers are used in a wide range of applications varying from a mobile charger to huge industries. Thus, the rating of the transformers can vary from VA to MVA. VA is the voltage and current rating of a transformer. Thus, based on the applications, transformers with different windings are used. There are different types of transformer winding machines used to manufacture transformers with different VA/MVA ratings. Besides this, different types of winding machines are required, depending upon low volume or high volume production. What are these machines? What is the significance of these machines in manufacturing winding? Are you intrigued to know more about them? Read the following post to get a detailed understanding of these machines.

 

What Are the Types of Transformer Winding Machines?

 

As discussed earlier, transformers with different VA ratings require different coil winding machines. Based on this, there are three main types of winding machines used. These three types of machines are as follows:

 

  1. Manual Transformer Winding Machines –

These transformer coil winding machines can either be operated by hand or with the help of a small motor. Transformer coils can be wound precisely by using the manual transformer winding machines. One of the major advantages of these machines is that they are light weight. This makes them portable and can be carried from one place to another easily.

 

  1. Programmable Transformer Winding Machines –

The programmable transformer coil winding machines are an advanced version of winding machines, which feature a 16 Bit microprocessor for smart operation. These machines also have a stepper motor, which is capable of winding up to 750 RPM. In these machines, various functions of a transformer are set-up and programmed. This is one of the biggest advantages of these machines, as programming these functions provides high level of precision in operation. Thus, coils of transformer can be wound easily. Some striking features of this achiness are:

 

  • They have a built-in production counter, which keeps an eye on the number of transformer coil winding.
  • There are a number of menu items, which can be programmed easily.
  • These winding machines are equipped with a speed control knob. This helps adjust the speed.
  • Another important and beneficial feature of these transformer winding machines is that they have a display.

 

  1. Automatic Transformer Winding Machines –

As their name suggests, the automatic transformer winding machines do their job with no or very less need of human interference. The advantage of using these types of winding machines is that they help reduce the labor costs. Various tasks can be fed to these machines, and they are operated using computerized programs. The multi-spindle feature of these machines help to make the equipment multi-coil winding. Multiple coil windings can be done simultaneously using these types of machines.

 

These were the three basic types of transformer winding machines used by a number of manufacturing firms. If you want to get more information about transformer coil winding machine, try to check out the website of DETZO Co., Ltd. – the company specializes in producing fully automated production line and winding machines. Learn more details please do not hesitate to visit DETZO immediately.

 

 

Article Source: https://www.armaturecoil.com/blog/transformer-winding-machines-their-significance-and-types/

How to Use A Drill Grinder?

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To help you quickly and easily sharpen drill bits, Earth-Chain provides Drill Grinder for customers. Here, I will teach you how to use the drill grinder. Learn how to operate the drill grinder, please check out the steps below:

 

  1. Set Up The Drill To The Collet Holder

Diagram #1 Set Up The Drill to The Collet Holder
Follow up the Steps 1, 2, 3, 4 for set up the drill to the collet holder. (Without tightening) as shown on diagram #1

 

  1. Set Up The Diameter of Drill

Diagram #2 Set Up The Diameter of Drill

  • Turn right the scale annulus to be “0” position.
  • Adjust the scale to meet the diameter of the drill. As shown on diagram #2

 

  1. Set Up The Drill To The Grinding Position

Diagram #3 Set Up The Drill To The Grinding Position
Insert the collet holder with drill and turn right, then tight the drill by collet holder for set up the grinding position. As shown on diagram #3

 

Attn: The scale annulus maybe not exact for the drill diameter, because of used drill or different model of drill anyhow, please always check the center edge of drill must be parallel with the gap of “Collet Holder”. As shown on the right diagram.

 

  1. Grind The Drill Tip

Diagram #4 Grind The Drill Tip

  • Turn on the power of the grinder.
  • Insert the collet holder with drill and push to the grinding wheel slowly, then move left and right repeatedly to sharpen the drill until the grinding sound disappeared.
  • Take out the collet holder with drill and change to the other side to grind again in same way as above mentioned. As shown on diagram #4

 

  1. Center Point Grinding Base Adjusting

Diagram #5 Center Point Grinding Base Adjusting
Adjust the center point grinding base to the suitable position. Turn right for bigger, turn left for smaller. As shown on diagram #5

 

  1. Grind The Center Point of Drill

Diagram #6 Grind The Center Point of Drill

  • Insert the collet holder with drill and push to the grinding wheel slowly, then move left and right repeatedly to grind the center point of drill until the grinding sound disappeared.
  • Take out the collet holder with drill and change to the other side to grind again in same way as above mentioned. As shown on diagram #6

 

Notice:

Please clean the grinding chip often for avoid the chip scrape to the grinding base and keep using life.

 

Earth-Chain drill grinder is guaranteed for one year under normal operating (expendable parts and wheels are exceptions)

 

If you need more information about drill grinders, please do not hesitate to check out Earth-Chain website. And feel free to send inquiries to let them know your requirements.

 

 

Earth-Chain Enterprise Co., Ltd.

No.551, Sec. 1 Gangbu Rd., Wu-Chi, Taichung 43546, Taiwan (R.O.C)

Tel: 886-4-2630-3737

Fax: 886-4-2630-3636

Email: ece@earth-chain.com.tw / www.earth-chain.com.tw

 

Keep Your Screen Changer In the Flow

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The screen changer plays an essential role in generating quality extrudate. Here’s what you need to know to keep it functioning properly.

 

There are many different designs of screen changers on the market today, from manual slide plates to constant-pressure and continuous backflush or scrapper designs, and each one comes with its own set of strengths and weaknesses. As a processor, you need to know these in order to make the best choice of screen changer for your particular application.

 

This article will focus more on general process troubleshooting as opposed to machine-specific issues, but it’s important to note that a large percentage of problems that extrusion processors have with their screen changers occur because the screen changer they’re using is not the best design for their application. Each specific extrusion filtration application should be closely examined prior to specifying a screen changer for the project.

 

FILTRATION MESH

Every processor wants the best filtration they can get for the area of filtration they have. Very few, however, utilize a screen-pack configuration fully optimized for their process. Take as an example a situation in which an operator is attempting to extend a production run between screen changes. As the screen becomes occluded, head pressure rises and eventually causes the wire cloth to fail. A simple operator solution is to pile on additional 20-mesh screens for increased strength.

 

A better solution would be to increase the support strength of the base screen, using a heavier-gauge 10-mesh screen layered with a single 20-mesh screen. The 10- and 20- mesh screens will support each other by working at two levels. The end result is the ability to run longer between changes, but without the unnecessarily high pressure drop and resulting increase in shear heat. Any increase in pressure-induced shear is best avoided, since this will generate higher melt temperature at the discharge end of the extruder, creating a higher demand on downstream cooling capacity and potentially reducing output.

 

Most screen-changer suppliers offer process-support services that include pressure-drop calculations. These are simple to perform and factor in material viscosities, breaker-plate open area, and screen open area to arrive at the best screen-pack configuration for the process and operating environment. This service is normally a free and simple means to optimize polymer flow performance.

 

TEMPERATURE CONTROL

Another issue occasionally attributed to screen changers is temperature fluctuation. Best practice is to stay alert to gauges, heaters, and heater circuits. Monitoring these on the screen changer may not be as critical as checking the extruder and feed screw, but it can help spot an issue before it becomes catastrophic.

 

Another tip is to optimize the number of heat zones necessary to balance temperature across the screen changer. More specifically:

 

  • Hydraulic slide-plate screen changers are best served by three zones—a body zone and independent zones for the each end of the slide plate. Many processors wire these machines into a single control zone, resulting in too much or too little heat to the slide plate. This can destabilize the melt profile and cause material burning in the off-line breaker plate.

 

  • Continuous bolt-type screen changers are normally best served by a single control zone, but as these machines increase in size, additional body zones help balance the heat. Bolt-type continuous screen changers heat the bolts by conduction from the body. If heat is unbalanced, the body can shrink onto the bolt and generate high enough clamping forces to prevent movement of the bolt.

 

  • Machine adapters are also normally best served with independent heat control. This, however, will vary with size.

 

PRESSURE FLUCTUATION

Streamlining the polymer flow through the screen changer will also affect process stability. For sensitive materials or those with unique flow characteristics, CFD (computational fluid dynamics) modeling software can be utilized to optimize screen-changer flow passages and minimize material residence time. Along this line, adapter length, steps and transitions, and polymer inventory between the screw tip and screen pack can be critical to establishing best flow while minimizing polymer degradation points and thermal stratification.

 

Vent cycles on continuous screen changers can influence pressure stability. Most bolt-type screen changers can see up to 50% of the available filter area removed from the process for screen change. While this naturally causes a rise in head pressure, the flow rate and die pressure normally remain relatively stable. The issue arises with the reintroduction of the clean screen. Vents machined into the bolts divert a small portion of the polymer melt to prefill and purge air from the incoming screen pocket. The resulting slight drop in die pressure can be minimized by operator finesse or more precisely by PLC control. Constant-pressure screen changers, such as rotary wheel designs, are not normally subject to these issues. One auxiliary that can help tremendously with fluctuating pressure is a gear pump, which can tolerate upstream pressure swings while holding the die pressure stable.

 

LEAKAGE

Leakage is a problem with almost all screen changer designs as they age, but most noticeably with slide-plate models. This type of screen changer relies on manually adjusted or pressure-activated seals and is subject to wear and tear from the movement of the slide plate, degradation of the seal-pressure ring, and damage from dislodged screens. Seal maintenance for these machines can be required as often as weekly to once a year. Maintenance can lead to tear down and reassembly, which can be a time-consuming, expensive process. Even before it reaches this point, the housekeeping required keeping the slide plate clean and preventing polymer from leaking onto wiring and other equipment is significant.

 

One way to minimize leakage on a system like this is to increase the head pressure. Your intuition might tell you lower pressure would be better because it would put less strain on the system. However, because the seals are designed to respond to pressure in the extruder, they are only working at their peak when the pressure is higher. At a lower pressure, the seals will relax slightly. When the extruder is idle or running at drool speed and there is very little pressure being exerted on the seal, it becomes easy for lower viscosity material to leak out. One newer slide-plate seal, an all-steel, segmented pressure-ring design, addresses these problems and caries a lifetime leak-free warranty regardless of temperature and low viscosity, making this seal the first to operate leak-free on high-temperature coating applications.

 

Material leakage on bolt-type or other close-tolerance rotary wheel machines that operate without a mechanical seal can likewise occur over time; but with these designs, leakage is almost always caused by mechanical damage. These precision-machined screen changers are typically designed for a fairly narrow material viscosity range.

 

As such, you should not apply a machine designed with clearances for high pressure and high viscosity to a low-viscosity process without approval or modification from the supplier.

 

RESIN CONTAMINATION, DEGRADATION

The primary purpose of a screen changer is to filter out contaminants from the melt stream; but the fact is, screen changes almost inevitably introduce contaminants, some of which get into the die. These result from imperfect cleaning of the slide plate, bolt, or wheel. For example:

 

  • This can occur on a slide-plate screen changer as the upstream and downstream seals scrape material residue into both sides of the oncoming screen pocket. Upstream contaminants are caught on the screen. Downstream contaminants flush out into the die.

 

  • A continuous or constant-pressure screen changer can experience this as well, but to a much smaller degree. The gap between the bolt or wheel and housing is measured in microns on the downstream side. The rare contaminant that makes it through this clearance to enter the melt flow is only consequential to the most demanding of applications, and for these few occasions, secondary, long-life canister filters will catch anything that comes through.

 

Many processes do not have to run continuously or require 100% quality and can overlook contaminants during screen change. However, if your customer has zero tolerance, you’ll need a different kind of screen changer. There is no way to continue using a slide-plate screen changer without introducing some level of contaminants or material degradation from the offline breaker plate. To solve this, a continuous bolt-type or rotary-wheel screen changer is a better solution.

 

LOCK-UP

Continuous screen changers that use no mechanical seal utilize precisely machined clearances to affect a polymer seal. These same clearances provide lubrication between the bolts or wheel and housing and must be maintained to avoid locking up the machines. Lock-up (jammed bolt or wheel) can be a result of various things, usually preventable with correct operator usage. The leading cause of lock-ups occurs when the bolts or wheel are not cleaned and lubricated regularly.

 

Many processors with a bolt-type or rotary-wheel screen changer have bought these continuous-process machines because they have no mechanical seals and run reliably and leak-free for years on end. While these advanced designs certainly require less upkeep than a slide plate, maintenance during screen change should not be neglected.

 

Over time, excess buildup of polymer can plate onto the bolt or wheel surfaces, reducing required clearances and eventually requiring more hydraulic pressure to shift than is available from the power unit or mechanical drive.

 

This stuck bolt or wheel is easily preventable with regular cleaning. A lock-up requires a shutdown and reheat process that can take up to 8 hr or more. Doing daily maintenance and cleaning of the piston takes 5 to 10 min and can save a considerable amount of downtime. “The biggest issue is getting into the mindset of cleaning the whole bolt,” says Marty Danco of Verity Resins, a recycler and compounder based in Forest City, N.C. “When you lock it up, there’s no way home, it’s locked up for good. Using proper copper gauze, the bolt should be cleaned every day—not just the top, but underneath it and on the sides.”

 

The necessity of regular maintenance also holds for breaker plates. Over time, material will carbonize on them, closing off the holes, which raises head pressure and eventually compromises output. Breaker-plate clogging is also easily preventable. The best solution is to make sure to have a clean spare. Swapping these breaker plates out even once a week is great preventive maintenance to ensure it never reaches the point where the process or the final product is impacted.

 

Most leading screen-changer suppliers are excellent resources to refer your troubleshooting issues to. Doing so, instead of relying solely on your maintenance crew, can often reduce your downtime and repair expenses, eliminate some problems before they occur, and potentially point you to a better process solution than the machine currently in service.

 

If you need more information about plastic extruder screen changer, please do not hesitate to check out the website of Hsin-Long Thread Rolling Machine Co., Ltd. – the company provides kinds of blown film extrusion machines, die head, air ring, bubble cage, etc. Learn further details, please feel free to send inquiry to Hsin Long.

 

Article Source: Plastics Technology

How to Increase the Process Speed of Die Sinking EDM

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Developments in the EDM process and its technology along with improvements in accuracy, automation and micro-mold making technology can pay enormous dividends to the domestic mold making industry.

 

Speed Is Not the Solution

Increasing drive speed is one solution to improving the speed of die sinking EDM. In this way the unproductive times for lifting movements are reduced; however, the gain in speed is limited to small electrodes and very deep cavities. In addition, above a certain speed the electrode wear is considerable and very high axis speeds result in extreme strain on the mechanism, make the machine more expensive and shorten its working life. Therefore, it is wrong to believe that a general increase in the process speed is only to be achieved by rapid lifting movements. The contribution of fast axes to the machining process is just one supplementary aspect to a complex interaction that encompasses the generator, process control, gap width regulation and the mechanism. And die sinking EDM requires intelligent flushing.

 

Potential Lies in the Flushing

You can imagine the EDM process as being a balance between the EDMed and evacuated material in the gap. If this balance is not present, then either you flush the machining area unnecessarily—involving a loss of time and additional instability of the process—or you EDM the same particles several times, which cannot be removed from the gap sufficiently.

 

Die Sinking EDM

Before the material can be evacuated from the gap you must remove it from the workpiece. So how can you achieve more removal? As in the case of all optimization problems, the greatest gain potential lies where the efficiency is smallest. The efficiency of a single discharge with a cathodic poled workpiece is theoretically about 25 percent.1 In addition there are some factors that make the efficiency even worse (e.g., process control problems, non-ideal flushing conditions, small gap width), so that realistically you must reckon with an efficiency of less than 10 percent.

 

Removal and Surface Quality Determine the Time Requirement

In the case of EDM, the objective is always to optimize the removal performance of the machining on one hand, and to achieve the surface quality of the workpiece to be machined on the other hand. The workpiece, when machined, is intended to display a certain final roughness and a certain form precision. In addition, two conditions are called for:

 

  1. As small a thermally influenced area of the workpiece surface as possible
  2. As low an electrode wear as possible.

 

These marginal conditions determine the machining time and costs for workpiece production. In practice, a sequence of technological parameters is used because starting out from the roughing to finishing settings, the pulse energy is gradually reduced until the required technological results are achieved. Once again the law of nature applies: you can quickly achieve results of modest quality, but only slowly results in high quality.

 

Physical Processes Show a Solution

The approach toward an ideal state means moving the characteristic curve in the direction of the arrow. That means faster EDM with the same gap width, roughness and wear. If, up to now, the discharge energy of the EDM pulses was increased, regrettably you also only had greater roughness and a greater gap width so that the gains in speed during roughing were lost again through longer finishing. You will find a way to a solution if you return to the basics of EDM theory—to the physical processes leading to the formation of the spark and metal removal.

 

During the discharge, you can identify three main physical phases in succession:

 

  1. The Build-Up
  2. Discharge
  3. Fade Phases

 

In the first phase the discharge canal is built up. After passing through the working medium, the current flows almost exclusively on the surface area of the discharge canal and the anode is partially evaporated by the electron bombardment. The electrode wear mainly takes place here. Every pulse—whether contributing intensively to removal or not— causes microscopic wear. In the discharge phase, the electrical energy supplied causes melting or evaporation of material mainly on the workpiece. The fade phase begins with the switching off of the power supply. The plasma canal collapses and the partially evaporated, partially liquid material is ejected.

 

When to Interrupt Pulses

During the discharge, a crater forms in the workpiece. Fundamental studies of discharges have shown that the growth of the crater in the workpiece stagnates from a certain time. This is because a balance forms between the energy supplied and the energy lost, as well as energy that is used for the maintenance of the plasma and the heat loss to the workpiece and dielectric. This asymptote of the crater growth can be recorded in real time from the spark voltage and current.

 

However, why is the asymptote of the crater growth so important? Because this is the right moment to interrupt the pulse. It is unnecessary to let a pulse last longer if the target radius of the crater and the required roughness have been achieved. You can begin with the next pulse immediately. The time required by the pulse to reach this state also is not constant, as the speed with which a discharge reaches a certain spark base diameter depends on the macroscopic situation in the gap and the local geometry in the spark discharge area. With this first measure alone, you will optimize the number of discharges per unit of time and increase the removal rate.

 

When to Increase the Current

If you now observe the charge’s fade phase you will see that the removal from the workpiece is caused by the collapse of the plasma canal. The sudden drop in pressure—triggered by switching off the power—causes the evaporation and ejection of superheated material. The plasma canal has a very high temperature and pressure. The gradient of its collapse influences material removal. The more abruptly the energy disappears, the better the crater material will be ejected. In order to enhance this effect, a special trick is employed: before the pulse is interrupted, the current is increased briefly. The idea of increasing the pulse current is not new, the innovation is the definition of the point in time when this increase is to take place. The increase in the pulse current has no consequences for the roughness, wear or gap width, but does increase the removal. In addition, as the removal per pulse is greater, you need fewer pulses for the machining, and therefore the wear sinks.

 

Removal Rate Doubles in Part

This new machining strategy (asymptote detection, current increase and pulse interrupt) is the subject of a patent application for its use in new EDM die sinking systems. The results are in accordance with the theoretical reflections, especially where good flushing is guaranteed (e.g., pre-machined workpieces). For these machining jobs removal rates have doubled.

 

Generator Brings Striking Improvements in Performance

The innovative generator offers an increase in productivity of approximately 30 percent; however, up to 100 percent with pre-milled molds that occur increasingly nowadays through synergies with HSM. This refers to all roughing and finishing using copper and graphite electrodes. The advantages are particularly great with good flushing conditions and pre-milled workpieces. These convincing results explain that it is possible to increase the speed and productivity of die sinking EDM, and the potential for improving this technology is still considerable.

 

If you need more information about die sinking EDM, please try to visit the website of Excetek Technologies Co., Ltd. – the company is the well-known brand for its EDM machines. Get more details about Excetek, welcome to check out their product pages and feel free to send inquiry to them.

 

Article Source: MoldMaking Technology

Get Some Information About Bubble Cage Before Buying…

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Why Do You Need Bubble Cages?

Blown film extrusion is the process that involves extruding a tube of molten polymer through a Blown Film Die (Single or Multi-Layer), which is a vertical cylinder with a circular opening. Air is injected through a hole in the center of the die creating a bubble, several times its initial diameter. The bubble is pulled upwards and an Air Ring blows air onto the film to cool.

 

Bubble cages reduce the turbulence caused by the cooling air stream when it hits the bubble. The Bubble Cage reduces movement that the bubble would otherwise have and prevents the bubble from losing stability. More stability results in increased production as well as improved quality.

 

Recommend Bubble Cages Supplier

If you have any interest in Bubble Cage, I recommend that you can visit the website of Hsin Long Thread Rolling Machine Co., Ltd.

 

Hsin Long Bubble Cage

Hsin Long Bubble Cage

 

  • The wires of stabilizing ring with SUS304 for increased.
  • Easy to adjust.
  • Single or double layer assemble easily.
  • Mass production, competitive prices.
  • Choice of various ring diameters.

 

Learn further details about bubble cage or other blown film extrusion machine, please do not hesitate to check out Hsin Long product pages and send inquiry to them.

 

 

Article Source: Mark One Machinery

Benefits of Having a Precision Lathe

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For complex parts and components, you will always need professional precision CNC machining services. However, for prototypes, simple parts, and short runs, there are also benefits of owning a high precision lathe. Although the machine is automated, it gets its instructions from a human who enters written code. Therefore, to own a machine, you also need an operator qualified to provide it with instructions.

 

CNC machine programming may not be rocket science, but it does require knowledge and skill. However, being in control is the greatest benefit of owning a machine. You have the opportunity to produce what you need whenever you need it. Whether creating a protocol or processing a large run, you have full control. Just remember that there is a financial investment in buying a CNC machine. With many different types of the CNC machine, you can always purchase the one that you would use most and then hire a manufacturer for the other work.

 

Types of CNC Machines

 

Following are the five types of machines most commonly used, although there are others. As you can see, each machine offers distinct benefits.

 

  • Router – A CNC router works by engraving plastic, wood, or metal. Following the entered code, a router can perform simple and detailed engraving tasks.
  • CNC Laser – One of the more advanced types of machine, the CNC laser is similar to a cutter with the exception that it cuts wood and metal. In some instances, this machine also cuts plastic. Regardless of the material, the finished product is perfect.
  • CNC Milling – Widely used, the CNC milling machine moves cutters as well as other tools for cutting metal pieces into specified shapes and sizes. Based on the number of axes that a milling machine has, it falls under several classifications.
  • CNC Lathe Machines – These machines are extremely accurate, but also precise, easy to operate, and capable of producing repeatable parts and components. With CNC lathe machines, you can make 3D molds and shapes out of wood, plastic, and metal.
  • CNC Plasma Cutters – While similar to a CNC router, a plasma cutter setup is not as challenging. With this machine, you can produce 2D molds and shapes out of metal.

 

Seeking Professional Assistance

 

There is nothing wrong with owning your own CNC machine and being in control of production. However, when you need outside help, you can try to send inquiry or contact with SHUN CHUAN Machinery. They are the professional and reliable manufacturer of CNC lathe machines. Get more information about precision lathe and other CNC machines, please do not hesitate to check out Shun Chuan website: www.sunmaster-cnc.com and contact them immediately.

 

Article Source: https://www.nexgenmachine.com/benefits-of-having-a-precision-cnc-machine/

Plastic Extrusion: Advantages and Disadvantages of Plastic Extrusion

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Plastic Extrusion

Plastic extrusion is the process where plastic materials are converted from solid to liquid and then it is reconstituted into finished products. In other words, plastic is melted down and then reshaped into useful items. There are some advantages to plastic extrusion, but there are also a few disadvantages that must be considered.

 

Advantages of Plastic Extrusion

3 of the major advantages of plastic extrusion are as follows.

 

  • Low Cost: Compared to other molding processes, plastic extrusion molding has a low cost and is more efficient. The extrusion molding process uses thermoplastics and they undergo repeatedly melting and hardening, this allows the waste to be reused rather than be discarded. Raw material and disposal costs are lowered. Plastic extrusion machines operate continually and this reduces the chances of inventory shortage. It also allows for 24-hour manufacturing.

 

  • Better Flexibility: Extrusion molding will provide considerable flexibility in the products being manufactured with a consistent cross section. As long as the cross section stays the same, the extrusion molding can produce complex shapes. Minor alteration to the plastic extrusion process the manufacturers can use it for plastic sheets or produce products that mix plastic attributes.

 

  • After Extrusion Alterations: Plastics remain hot when they are removed from the extruder and this allows for post-extrusion manipulations. Many manufacturers will take advantages of this and use a variety of roller, shoes and dies to change the shape of the plastic as needed.

 

Disadvantages of Plastic Extrusion

Plastic extrusion has also some disadvantages.

 

  • Expansion: Once the hot plastic is removed from the extruder it will many times expand. This is called die swell. It is problematic to try and predict the exact degree of expansion. Because it is hard to predict the exact expansion, manufacturers often accept significant levels of deviation from the dimensions of the product.

 

  • Product Limitations: Extrusion plastic molding does place limits of the types of products that can be manufactured. There are alternatives that require an investment in a different type of extrusion equipment.

 

If you have any interest in plastic extrusion machinery, I recommend that you can visit the website of Leader Extrusion Machinery Company Ltd. They have more than 20 years’ experience designing and manufacturing plastic extrusion machinery. And the company specialty is manufacture of PP, PS, PVC, PC sheet extrusion lines; and PP, PC PET hollow profile sheet extrusion lines.

 

Learn more information about plastic extrusion machines, welcome to send inquiry to Leader Extrusion Machinery Company.

 

 

Article Source: http://civilengineersforum.com/plastic-extrusion-advantages-disadvantages/