Wexco Barrels
WEXCO employs sophisticated centrifugal-casting processes to manufacture its high-performance bimetallic cylinders.
The term Bi-metallic indicates the fusion of two different metals in a high-temperature furnace that subjects the two metals to temperatures of more than 2000oF (>1100oC).
High revolution spinning of the white-hot cylinder fuses the inlay alloy to the bore wall.Subsequent carefully controlled cooling creates a super-hard, highly uniform lining in the cylinder bore that is further subjected to ultra-precise honing processes. The finished bore lining is at least .050" [1.27 mm] thick. Double and triple lining thicknesses are available for specific applications.
WEXCO offers several cylinder-lining alloys designed to meet your specific processing requirements. The listing below provides a general overview of the various WEXCO inlay alloys and their unique features. We will gladly assist you in selecting the most appropriate WEXCO inlay alloy for your processing application.
WEXCO bore-lining alloys for spun-cast high-performance bimetallic cylinders:
WEXCO 555 Alloy
WEXCO 555 is recommended for use where severe corrosive conditions are encountered. It is a cobalt-nickel base alloy with high chromium and boron content for excellent corrosion resistance against hydrochloric and other acids. It has a dual-phase microstructure with complex borides that provide excellent wear resistance: over 10 times the service life of nitrided barrels in severely corrosive atmospheres. It has a typical hardness range of Rockwell C 50-55.
WEXCO 666 Alloy
WEXCO 666 is recommended for applications that process abrasive materials. It is a nickel-boron base iron with a high hardness, martensitic structure in cementite matrix. It has excellent abrasion resistance and a low friction coefficient (0.0) for prevention of screw galling. It provides a service life of at least four times that of nitrided barrels, and a hardness range of Rockwell C 60-65.
WEXCO 777 Alloy
WEXCO 777 is recommended for use where extremely abrasive and moderately corrosive conditions are encountered. It is a high tungsten-carbide content alloy with a matrix of a chromium-boron-nickel alloy. Tungsten carbide provides the primary wear resistance with the high chromium boride-content matrix alloy providing additional wear and corrosion resistance.
WEXCO 777 has a macro hardness of Rockwell C 62-68; however, over 80% volume of this alloy is occupied by tungsten carbides and chromium borides which show a micro hardness of over DPH 4000 (over Rc 70). It is one of the highest wear-and corrosion-resistant alloy available for bimetallic cylinders. We also recommend WEXCO 777 barrels for use in custom processing shops where the same machine is used to process several different kinds of resin material.
WEXCO BO-22 Alloy
WEXCO BO-22 is ideal for the processing of Fluoropolymers and Polyvinyl Chloride resins under severely corrosive conditions. It is a nickel rich boron base alloy which contains 12% molybdenum, and a matrix rich in complex borides and carbides. These elements cause it to maintain its high temperature hardness. It has a typical hardness of Rockwell C 50 or above (at 70 F).
WEXCO BO-22 bimetallic cylinders are subjected to a HIP process (Hot Isostatic Pressing) that essentially prevents any porosity in the bore lining. Molybdenum and its alloying elements are far superior in corrosion resistance against halogen containing elements. This reduces acid attack when compared with conventional nickel-cobalt base alloy, e.g., WEXCO 555 or "equivalent" liners produced by competing manufacturers.
WEXCO Durocas Alloy (with 5-Year Wear Warranty!)
WEXCO Durocas lining material for bimetallic cylinders offers a high degree of wear and corrosion resistance. It is recommended for the toughest and most demanding injection and extrusion processes. Durocas is a spherical tungsten-carbide combined with a chromium- boron-nickel matrix. The spherical tungsten carbide provides outstanding primary wear resistance allowing for a micro hardness of over DPH 4000 (too hard for Rockwell C scale measurement.)
The chromium boride, along with the high chrome content, further enhances wear and corrosion resistance. The high density of spherical carbides makes this WEXCO lining material the best choice for longest-lasting performance.
WEXCO Durocas lined bimetallic cylinders are warranted against excessive wear: For a period of 5 years from date sold, WEXCO guarantees that Durocas cylinders will not wear more than .010[0.25 mm] (total) on the bore diameter.
WEXCO High-Performance Cylinders with one-piece Tool Steel Liners
WEXCO non-spun bimetallic tool steel cylinders consist of a special cylinder steel and a unique one-piece (i.e. non-segmented) tool steel liner.High-performance one-piece Tool Steel Cylinders only from WEXCO!