Segmental construction

Pistons may be of segmented construction to permit the use of one-piece wear bands. One-piece wear bands are a requirement in API 618. Pistons have a problem in common with humans—a weight problem. Weight in a piston contributes directly to the compressor shaking forces and must be controlled. For this reason, aluminum pistons are often found in larger low pressure cylinders. Hollow pistons are used but can pose a hazard to maintenance personnel if not properly vented. If trapped, the gas will be released in an unpredictable and dangerous manner when the piston is dismantled. 

Bostik, Inc., formerly Bostik Findley, Inc., is a leading global producer of adhesives and sealants. The firm operates in five segments construction and distribution performance adhesives nonwovens/tape and label global transportation and flexible laminating. The construction and distribution division manufactures flooring installation adhesives for tile, stone, hardwood, carpet and vinyl caulks, elastic adhesives, aerosol adhesives, fire-retardant adhesives, epoxies,... 

The first approach has been pioneered on Italian Autostrada bridges in the mountainous areas of Northern Italy (Pedeferri, 1992). Previous construction experience had shown that it was very difficult to prevent chloride ingress. Therefore cathodic protection anodes were either built into the deck or applied as part of the construction process. The bridges were post-tensioned segmental construction with tendons in grouted ducts. 

FIP - Proposal for a standard for acceptance tests and verification of epoxy bonding agents for segmental construction... 

Epoxy adhesives were used in 1978 during the construction of the U.S. s first segmentally constructed cable-stayed bridge across the Columbia River(15). Here the deck is made monolithic by a combination of post-tensioning and compressive forces from the horizontal components of the stay cable forces the epoxy mortar is called upon to provide both shear and tensile resistance across the joint. 

Table 7,2, Programme of testing when choosing a bonding agent for segmental construction (Ref, 14)...

Creep of the epoxy resin system under sustained load has always been of some concern. However, with a thin glue-line and at the relatively low stress levels encountered in segmental construction, compressive creep should not be a problem with most epoxies(2). 

A similar concept to glulam and concrete segmental construction can involve the fabrication by bonding, usually with epoxides, of awkward or special shapes and units made of concrete or clay brick. Examples include special roof tiles and building blocks formed by cutting and bonding standard production shapes to provide new forms. 

The drive chain wheel at the head of the elevator is of three-piece segmental construction and has no teeth, force transmission being effected solely through friction, The great weight of the chain and buckets ensures that high frictional... 

Since connecting the four alternate corners of a cube with line segments constructs a regular tetrahedron, the angle between any two of the axes shown in Figure 21.5a is called the tetrahedral angle and is equal to 109 degrees, 28 minutes, 16.39... seconds... 

Easily installed in the column (segment construction). This requirement is especially important in case of a column operating at high pressure. In case of a colunm, which can be open for repairs fiiis is not so impoitont. 

Tools can be of segmented construction for high complexity work. 

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