2017-10-14 Other Advantages of Using a Melt Pump

The prime reason for adding a melt pump to an extrusion system is to improve the throughput stability - from between 5% t0 8% typical for an extruder used alone to the 0.1% of the typical melt pump with differential pressure control. There are, however, other major advantages in using a melt pump at the output of the extruder: The output can almost always be increased - typically by 15 t0 25%. The throughput curve of an extruder used alone as shown in Fig. 6.2 illustrates that the screw type pump in an extruder is a very inefficient pump. If there is any significant pressure at the die, the ou

2017-10-14 Melt Pump for Extruder

The melt pump for extrudersimply takes away whatever the extruder is pumping. As soon as the output of the extruder is sufficient to fill the teeth, however, the situation changes dramatically. Now it is just as if the extruder is pumping into a brick wall. The melt pump can accept only so much plastic and no more. Attempting to pump more plastic skyrockets the pressure upwards untilit blows the safety blow-out plug, at which time the pressure drops to zero, and the ball game is over Our problem, however, is that if we are going to use the melt pump to meter out the plastic, operation has to b

2017-10-14 Microprocessor Melt Pump Control

As mentioned earlier, the performance of any extrusion line can be significantly enhanced though the use of automated closed-loop controls. It is, however possible to control the extrusion line manually, and many people still do. Back pressure experienced by extruder when the melt pump turns at constant speed and extruder speed is gradually increased. Manual control, however, is not an option for melt pumps . In the following we will explain why it is simply not practical to control a melt pump manually. The problem lies in the nature of the interaction between the melt pump and the extruder.

2017-10-14 Throughput of a melt pump with simple input pressure control

By far the best way to get a stable throughput from an extruder is to use a melt pump on the output. In concept the melt pump is very simple. It uses a pair of closely meshed gears, placed in the main plastic stream. The teeth are filled at the input,leveled off by the housing, and then emptied at the meshing point. The device can be thought of as measuring cups on a wheel. The teeth are loaded at the input and emptied at the output. The important thing to note is that the gear pump is a positive displacement device. There is no channel open between input and output, as in a screw type pump. E

2017-09-28 The external gear pump choose

The external gear pump is a positive displacement (PD) type of pump generally used for the transfer and metering of liquids. The pump is so named because it has two gears that are side-by-side or external to each other. (This nomenclature differentiates it from an internal gear pump, which has one gear positioned inside the other.) The gear pump is a precision machine with extremely tight fits and tolerances, and is capable of working against high differential pressures. The working principle of

2015-09-23 Gear Pumps Types and Applications

Gear Pumps Types can be divided into micro gear pump for solidifying fluids, pumps for paint plant / lecithin / sealant spray automotive industry / thermo forming plates, and booster pump as per gear pumps applications . Gear Pumps Types an

2015-09-22 Gear Pumps for Chemical Industry

Gear Pumps for Chemical Industry include many types, and they have different features and applications. Batte is a famous chemical gear melt pump designer, manufacturer and supplier in China. Gear Pumps for Chemical Industry applications an

2015-09-22 Stainless Steel Chemical Pump

Stainless Steel Chemical Pump is for the chemical and pharmaceutical industry. Robust and modular gear pump by Batte Pump Systems. Highly efficient, highly precise, corrosion resistant and easy cleanable. Stainless Steel Chemical Pump featu

2015-09-19 Chemical Pumps

Chemical Pumps are high precision gear pump for conveying low to medium viscosity fluids, and for safe, relaible metering tasks, and food industry, such as conveying butter, margarine or vegetable oils. Chemical Pumps applications: Chemical

2015-09-19 Divert Valve

Divert valve is a kind of auxiliary equipment, and used to aid in redirecting the flow of the melt stream. Divert Valves perform a variety of functions for the polymer, food, hot melt, and chemical industries. Divert Valve Features: Compact