Filament-wound cylinders

There are a number of general references available that contain detailed descriptions of the winding process and equipment itself [5,6], The purpose of this work, however, is to focus on the relationship between processing conditions and final part quality for both thermosetting and thermoplastic matrix filament wound cylinders. In the subsequent sections, an overview of the process will be presented, followed by detailed descriptions of current process modeling techniques and methods for determining cylinder quality. 

There are several resources available for designing filament-wound cylinders. In general, filament-wound cylinders are classified as cylindrically orthotropic. Adjacent helical plies, loading conditions can be determined by following the principles of laminated plate theory [7]. When applying laminated plate theory, the plate consists of the cylinder wall. In this case, the effect of cylinder curvature is neglected, and the Q and z axes are considered the planar axes of the plate. Failure criteria applied in laminated plate theory, such as maximum stress or strain, or the quadratic Tsai-Wu failure criteria [7] may also be applied. Several specialized loading cases have been studied. 

Studies with filament-wound cylinders have been extended to investigation of design details that arise in realistic pressure hulls such as closures, openings, and joints. The entire pressure hull was designed to obtain a collapse depth of 9,150 m (30,000 ft) and to sustain 10,000 excursions to a depth of 4,575 m (15,000 ft) without loss in overall... 

Ovaloid n. A surface of revolution symmetrical about the polar axis that forms the end closure for a filament-wound cylinder. 

Exemption cylinders. Many lightweight filament wound cylinders and high-strength steel cylinders are in use. Their specifications, uses and handling are as specified by DOT exemption. 

A filament wound composite cylindrical pressure vessel has a diameter of 1200 mm and a wall thickness of 3 mm. It is made up of 10 plies of continuous glass fibres in a polyester resin. The anangement of the plies is [O3/6O/ — 60],. Calculate the axial and hoop strain in the cylinder when an internal pressure of 3 MN/m is applied. The properties of the individual plies are... 

Tests on plastics in deep water have been extremely successful. As an example filament-wound RP cylinders and PVC buoys retained their strength. PVC washers and the silicone-seating compound used in steel-to-aluminum joints helped prevent their corrosion. Black twisted nylon and polypropylene... 

The laminate compressive hoop strength/stiflness of a filament-wound vessel can be evaluated using the externally pressurized ring test method [44] or the standardized ASTM D2586 test method. In the ASTM D2586 test method a filament-wound FRP cylinder is tested under hydrostatic pressure to simulate the loading conditions of a pressure vessel under an external pressure load. The main drawback of this test method is the influence of the end constraints on the test results. 

In the past, filament-wound parts consisted primarily of axisymmetric cylinders, spheres and domed vessels. Several manufacturing techniques have been developed that allow more complex shapes and curvatures while maintaining the cost effectiveness associated with process automation [52], These methods have emerged because of advances in programming software. These advances enable precise positioning of the moving head and allow real-time simulation of fiber paths. 

Unidirectional prepreg, aligned, unidirectional fabrics, pultruded (aligned) rods, filament hoop wound cylinders... 

The filament-wound sphere design structure provides another example of a balanced netting analysis system (Chapter 5). It is simpler in some respects than the closed-end cylinder. The sphere must be constructed by winding large circles omni-directionally and by uniform distribution over the surface of the sphere. In practice, distribution is limited so that a small polar zone is left open to accommodate a connecting fitting. 

This review concerns the structural behavior of filament wound RP cylindeis. Test specimens of thick-walled, unstiflfened cylinders with the... 

A typical filament wound tube is 300 mm diameter and 2 m long, but cylinders as large as 12 m diameter and others 38 m long have been produced. 

Liner (1) A continuous, usually flexible coating on the inside surface of a filament-wound pressure vessel, used to protect the laminate from chemical attack or to prevent leakage under stress. (2) In extruders and injection molders, the hard-alloy interior surface of the cylinder. Decades ago, some of these were separately fabricated and pressed into the steel cylinders. Today they are centrifugally cast into cylinders. 

Hernandez-Moreno H, Douchin B, Collombet F, Choqueuse D and Davies P (2008) Influence of winding pattern on the mechanical behavior of filament wound composite cylinders under external pressure, Compos Sci Techol 68 1015-1024. 

Additional patterns have been simulated, including near 0 to about 90 helices. Test cylinders have also been wound with roving. The graphical presentation is effective for conformation before winding and demonstrates the successful development of a numericeiUy controlled, filament winder. 

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