SOAP PLODDERS - SOAP EXTRUDERS
Soap plodders and extruders are essential machines in industrial soap manufacturing, used for refining, homogenizing, compressing and extruding soap into continuous bars. Simplex Refiner Plodders and Duplex Vacuum Plodders provide different refining and extrusion solutions for modern soap finishing lines.
Soap Plodders and Extruders
Soap plodders and extruders are essential machines in industrial soap finishing lines, used to refine, homogenize, compress and extrude soap into noodles or continuous soap bars. Different plodder configurations are available depending on the required refining performance, production capacity and type of soap. The main types include Simplex Refiner Plodders, Duplex Vacuum Plodders and Special Plodders.
Simplex Refiner Plodder
The Simplex Refiner Plodder is used to refine soap through a combination of intimate homogenization. The machine consists of a screw manufactured in aluminium alloy or stainless steel, a barrel equipped with a cooling jacket, a hopper for feeding the soap from the mixer, a heavy-duty gearbox and a basements. The barrel cooling system uses water supplied by a chiller to help control the soap temperature and avoid a reduction in production rate. At the end of the refining plodder, a refining screen and drilled plate with rotary blades are used to process the soap and produce refined soap noodles.
Duplex Vacuum Plodder
The Duplex Vacuum Plodder consists of two simplex plodders connected by a vacuum chamber. The first stage operates as the refining stage, using a drilled plate with blades, while the second stage works as the extrusion stage, using an extrusion cone to produce a continuous soap bar. The vacuum chamber between the two stages removes small air bubbles that may be present in the soap before final extrusion. This contributes to a more compact and homogeneous extruded soap bar. Modern plodders can use frequency inverters to adjust screw speed according to the processing requirements. The extrusion cone is heated to help obtain a smooth surface on the extruded soap bar.
Special Soap Plodder
Special duplex vacuum plodders have been developed to perform refining and homogenization without requiring a separate Simplex Refiner Plodder or Three Roll Mill. These machines can use specially designed combo-screws, characterized by two different diameters.
The larger diameter section provides efficient soap feeding, while the smaller diameter and longer compression section provides high homogenization and compression. These special screws can have a useful length of 8–10 times the screw diameter, while traditional plodders generally have shorter L/D ratios, like 3:1 or 4:1.
Twin-Screw Soap Plodders
Plodders can also be manufactured with twin screws instead of a single screw. Twin-screw configurations use two tangential and parallel screws and can be employed to increase production rate and improve soap homogenization.
Important Parameters for Soap Plodder Refining
Three important parameters determine the refining performance of a soap plodder:
Screw L/D Ratio
The L/D ratio is the relationship between the useful screw length and its diameter. A longer screw with more spirals works the soap at higher pressure and improve homogenization. For example, a screw with a useful length of 1,000 mm and a diameter of 250 mm has an L/D ratio of 4:1.
Refining Screen
The refining screen is installed before the drilled plate. Screens are classified according to the number of wires per inch. For example, a 20 mesh screen has 20 metallic wires per inch. 50 mesh screen provides a stronger refining action, while 20 and 30 mesh screens can be used when higher production rates and reduced soap heating are required.
Screw Design
The geometry of the screw also affects soap processing. Different designs can have a constant or increasing kernel diameter, as well as constant or variable pitch. The combination of these characteristics influences soap compression, homogenization and production rate.
Soap Plodders in the Finishing Line
The choice of plodder depends on the required number of refining stages and the characteristics of the soap being processed. A soap finishing line can combine Simplex Refiner Plodders, Three Roll Mills and Duplex Vacuum Plodders to obtain different levels of refining. Special plodders can also integrate refining and homogenization functions into a single machine. The Duplex Vacuum Plodder is particularly important for the final extrusion stage, where refined soap is compacted and extruded through a conical head to obtain a continuous soap bar.
Knowledge Content – Browse by Topic
01. WHAT IS SOAP
02. RAW MATERIALS USED IN SOAP MANUFACTURING
07. SOAP DRYING AND COOLING
08. SOAP FINISHING LINE
09. SOAP PACKAGING