Struktur des Fasses:

Der Zylinder und die Schnecke bilden das Extrusionssystem, die beide unter hohen Temperaturen, hohem Druck, starker Reibung und bestimmten Korrosionsbedingungen arbeiten. Gleichzeitig hat der Zylinder auch die Aufgabe, Wärme auf das Material zu übertragen oder dem Material Wärme zu entziehen.

Struktur des Fasses:

The barrel structure can be either integral or assembled:

1. Integral Barrel: The integral barrel is machined from a single billet. This structure is characterized by its ability to ensure high manufacturing and assembly precision, facilitate uniform heating, and simplify the setup and disassembly of the heating and cooling system.
2. Assembled Barrel: The assembled barrel is generally composed of several barrel segments. Compared to the integral barrel, it is easier to process and can be customized according to different usage requirements and product types. However, this structure demands higher machining accuracy. Assembled barrels often use flanges and bolts to connect segments, which disrupts the uniformity of heating, increases heat loss, and complicates the setup and maintenance of the heating and cooling system.

Barrel Materials:

Barrel materials typically include alloy steels like 30Cr and 38CrMoAl. Carbon steel or cast steel can also be used as the base material, with an alloy steel liner embedded inside to enhance wear resistance.

Forms of the Barrel’s Feeding Section:

Common extruders usually adopt the following two methods to improve the solid conveying capacity:

1. Longitudinal Grooves: Machining longitudinal grooves on the inner wall of the feeding section of the barrel.
2. Tapered Section: Making the barrel near the hopper section conical.

Longitudinal grooves in the head of the machine can only be machined on the section where the material is still solid or just beginning to melt. The length of the grooves is typically about 3~5 times the diameter (D). The main data for machining longitudinal grooves in common extruder barrels is shown in the table below.

The taper length of the inner wall of the barrel is generally 3~5 times the diameter (D). The taper size depends on the particle size of the material and the diameter of the screw; the taper decreases as the screw diameter increases.

Shape and Position of the Feeding Port:

The shape and position of the feeding port on the barrel significantly impact feeding performance. The feeding port should allow material to enter the barrel efficiently and freely without causing bridging. It should also facilitate the setup of the cooling system. The shape of the feeding port can be round, square, or rectangular, with rectangular being the most common in extruders.