Surface winder

The film is wound to film rolls using a contact/surface winder with an option for automatic roll change (Fig. 9, 4). The production process can be controlled automatically, keeping meter weight and thickness distribution constant (Fig. 9, 5). This device enables automatic quality control in the production process. 

Their weights can be very low to at least 16,000 lb. Diameters are at least up to 60 in. and widths at least up to 30 ft. Some rolls require roundness and surface finishes to be within 0.00005 in. (0.00127 mm). Many winders offer sophisticated features and are highly automated, but some are designed to answer the need for simplicity, versatility, and economy. There are surface winders with gap-winding ability for processing tacky films such as EVAs (ethylene vinyl alcohols) and the metallocene plastics. Information on these different types of rolls is provided in Table 18.1. 

The main function of a winder is to guide the film evenly into the roll form. To accomplish this, it must provide tension control on the film to produce evenly wound rolls. A secondary nip, either as part of the winder or just prior to the film entering the winder, is used to provide this tension control. Tension must be sufficient that the roll will not telescope when handled, but must not be so much that it causes crushed cores or center-roll bagginess. Tensions on center drive winders are generally tapered from the core to the outer wraps to compensate for the change in diameter of the roll. On a surface winder, the compensation is automatic because of the drive mechanism. When tension is being adjusted on a winder, it must be kept at or below 0.5% of the secant modulus of the film to avoid excessive stress in the film. One reason for this low value of recommended tension is that the film is not totally at equilibrium at the time it is wound into the roll. Dimensional changes occur as the film crystallizes or cools, and induce stress. 

Winders (Fig. 3.19) are used to collect the wound roll packages. They generally operate in a manner that produces rolls of constant web tension, as opposed to operating at a constant winding (rotational) speed. There are two primary winder types surface winders and axial winders. 

Because of their simple, economical design, surface winders tend to be the more popular of the two. They operate by employing a motor-driven contact roll at the him roll surface. The contact roll essentially lays the him onto the rotating him roll. As the him roll diameter increases, the axis of the him roll moves in a path that separates it from the contact roll, maintaining pressure at the surface. This system is used mainly for medium- and high-tension rolls. 

Axial (or center) winders are often used when low-tension roll packages are required. In these systems, the central axis of the him roll is motor-driven rather than the contact roll. This type of winder tends to be more expensive than the surface winder. 

Bundle Preparation. Packages of multifileiment yarns are backwound to prepare bundles necessary for the manufacture of a reverse osmosis module. A proprietary winder for this operation has been designed and constructed at Albany International Research Co. This device is capable of helically winding multifilament yarns into bundles around a mandrel. This is done in a manner such that the resulting bundle has uniform cylindrical dimensions and uniform fiber density. This minimizes channeling and optimizes exposure of membrane surface area. 

Simpler winder foundations—the geotechnical conditions at the surface collar area would have made the winder hold down for a ground mounted arrangement more comphcated in comparison to a tower arrangement. 

The production shaft is serviced by a groimd-moimted friction winder with a nominal production capacity of 3.5Mt/y and a hoisting depth of 1,100m. A surface conveyor system transports ore from the tipping bin at the shaft to a surface ROM stockpile adjacent to a new secondary crushing cuid screening plant. 

Can Surface Man Winder duty cycle handle the weight of the new 37 ton drum shaft Could the rope handle the additional load ... 

Permission is hereby requested for the temporarily relaxing of the requirements as stipulated in Regulation 16.34.1(a) and Regulation 16.34.1(b) as it pertains to the Kloof 4, Man Winder on surface, Winding Plant Certificate No 7586. This request is made in so far as it determines... 

On the electrical side it was determined that that NO trip out condition should be entered into. All scenarios were Risk Assessed and a work shopped. To avoid unnecessary and/or nuisance trip outs it was suggested that the following safety features be bridged out while slinging the new drum shaft for the Sub Vertical Rock winder using the Surface Man Winder. 

Slinging 37-ton S/V Rock Winder Drum Shaft Using Surface Man Winder Underlay Compartment... 

The largest diameter reduction occurs within less than 1 cm of the spinneret surface. Spinning of a mesophase pitch with 40-80% mesophase requires a melt viscosity of 10-40 MPa.s (or log 2.6 poise). This viscosity corresponds to a fiber forming temperature of 340-380°C, and requires a winder speed ranging from 100 to 500 m/min [15] [24]. Extrusion or melt spinning of 100% mesophase pitch melts can be carried out at higher viscosities and with higher winder speeds [6] [25-26]. 

Film and Sheet Lines Using the Roll Stack Process. There are no significant differences between the extrusion of fiat film and sheet. The main components of a sheet line are the extruder, the roll stack, the cooling section, the nip roll section, and the winder (see Fig. 23). The roll stack contains three rolls that are often referred to as polishing rolls. They are used to exert pressure on the sheet and to impart the surface conditions of the rolls to the plastic sheet. If a smooth surface is required, smooth rolls are used. If a textured surface is needed. 

Film Lines Using Chill Roll Casting. Thin films are often cast on a chill roll rather than extruded into a roll stack. The main components of a cast film line are the extruder, the film die, the chill roll imit, the thickness gauging system, the surface treatment imit, and the winder. 

After the tube has been biaxially stretched, the film needs to be annealed. This process can be done in several ways (Fig. 10). The most common is to insert into the tube a set of parallel bars. These bars have air flowing out on their outer surfaces that allow the film to slide over them. These bars are in an oven or ir-heating chamber. As the tube reaches the end of the annealing zone, it is split open and sent to the winder. 

A major part of film, sheet, coating, pipe, profile, etc. lines involve windup rolls. They include winders, dancer rolls, lip rolls, spreader rolls, textured rolls, engraved rolls, and cooling rolls. All have the common feature that they are required to be extremely precise in all their operations and measurements. Their surface conditions include commercial grade mirror finishes, precision bearings and journals are used, and, most important, controlled variable rotating speed controls to ensure uniform product tension control. 

By tradition and technical feasibihty, coating and supercalendering for surface quality improvement have been off-hne processes. Today both are increasingly integrated into the paper machine. The final activities in paper and board production are shtting of the full width reels into smaller rolls at the winder followed by packaging the rolls for shipment... 

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