Dual sheet forming

Figure 35.43 shows a general layout of a dual-purpose calender line for coating steel cord and textile cord. The heart of the production line is the four-roll calender in an S-configuration. Two mbber sheets are formed in the upper and lower nip. The thin sheets are guided to the middle nip and the cords are coated in the middle nip between the two rubber sheets. Generally outer roll bending is applied on rolls 2 and 3 to compensate the roll deflection caused by the nip force in nip 2. Rolls 1 and 4 can be set crossed respectively to rolls 2 and 3. 

Sheet molding compound (SMC) is a composite material that has been used as an alternative to steel for more than 30 years. SMC consists of a glass-fiber-filled unsaturated polyester and vinyl ester resin that has been compacted into a sheet. These sheets are then placed into compression molds and formed into body panels, and these panels are then coated mainly by dual-cure coatings. ... 

The standards in BS 2782 covering tensile testing are dual numbered with the corresponding ISO. Thus Method 321 [27] corresponds to ISO 527-1. Method 322 [28] to ISO 527-2. and Method 326E [29] to ISO 527-3 (Methods 326 A to C having been recently superseded). A standard not covered by ISO. however, is Method 327A [30]. which covers the tensile testing of PTFE products in various forms such as tube. rod. sheet, and tape. 

Wheel machines are designed specifically for dedicated products, such as picnic plates, dual-ovenable food trays, and takeaway coffee lids [8]. The wheel is a horizontal cylinder that contains dozens to hundreds of female or negative molds. The sheet is continuously extruded through the sheet die directly onto the slowly turning wheel. Vacuum pulls the sheet into the cool molds. As the wheel turns, the formed products are cooled. When the products are sufficiently cooled, the sheet containing the products is stripped from the wheel and fed to a conventional in-hne trimmer. 

The study of dual-layer asyimnetric hollow-fiber membranes formed by the phase-inversion process started in the late 1980s. In 1987, Yanagimoto invented dual-layer asymmetric flat-sheet and hollow-fiber membranes to improve the antifouling properties of membranes for ultrafiltration and microfiltration (Yanagimoto, 1987, 1988). Since then, Kuzumoto and Nitta (1989) simultaneously extruded inner and outer dopes containing the same polymer but different solvents and additives to improve water permeability. Ekiner et al. (1992) disclosed the procedures for the fabrication of dual-layer hollow fibers for gas separation. Li et al. (2002) developed a delamination-fiee dual-layer asymmetric... 

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