Expansion bolts

The process is divided into five steps (see Fig. 9) Ecovio is first processed by the extruder to form a melt stream with constant melt temperature and output rate (Fig. 9, 1). In the forming section, the melt streams of several extruders can be merged into one using an adapter feed block or a multilayer die. These devices control the flow of each stream to obtain an even layer distribution (Fig. 9, 2) [30]. Then, the melt stream is transformed into a flat film in the film die. The thickness distribution is controlled automatically by means of expansion bolts. 

In order to achieve a favourable load curve, the stator casing is mostly made in the form of a thick-walled hollow cylinder as a semi-finished forging of material C22.8 (as per VdTUV 350) for temperatures up to 350°C or an austenitic stainless steel. Its cylindrical construction makes it easy to calculate the load curve as described in the AD data sheets (Figure 4). The add-on components, the spacer with the pump casing and the motor sealing cover are bolted to the motor by means of concentrically arranged high-pressure expansion bolts. 

For the most robust fixing to masonry materials, an expansion bolt such as that made by Rawibolt should be used. 

The most well-known expansion bolt is made by Rawibolt and consists of a split iron shell held together by a steel ferrule at one end and a spring wire clip at the other end. Tightening the bolt draws up an expanding bolt inside the split iron shell, forcing the iron to expand and grip the masonry. Rawibolts are for heavy-duty masonry fixings. 

Most coils are firmly clamped (but not welded) to supports. Supports should allow expansion but be rigid enough to prevent uncontrolled motion (see Fig. ll-29b). Nuts and bolts should be securely fastened. Reinforcement of the inlet and outlet connections through the tank wall is recommended, since bending stresses due to thermal expansion are usually high at such points. 

Figure 6-33. The coupling hole alignment tool (CHAT) has a longitudinally split sleeve for greater expansion. Like the radial fit bolt, it is hydraulically tensioned, but there is no hydraulic separation of core and sleeve.

However, the sleeve is segmented, allowing eonsiderable expansion to turn the eouplings relative to eaeh other, elose the eouplings, and maintain alignment while the radial fit bolts are installed. 

Sheli Cover Bolted to Shell. Shell Cover Bolted to Shell. Floating Head Caver Baited ta Floating Head Cover Boited Tube Sheet or its Backing Ring. Expansion of Tube Bundle to Tube Sheet or its Provided by External Packing Gland or by Internal Bellows... 

The amount of movement to be taken up by the piping and any device incorporated into it can be reduced by the use of cold draw . The total amount of expansion is first calculated for each section between fixed anchor points. The pipes are left short by half this amount, and stretched cold, as by pulling up bolts at a flanged joint, so that at ambient temperature the system is stressed in one... 

When materials with different coefficients of linear thermal expansion (CLTE) are bolted, riveted, bonded, crimped, pressed, welded, or fastened together by any method that prevents relative movement between the products, there is the potential for thermal stress. Most plastics, such as the unfilled commodity TPs, may have ten times the expansion rates of many nonplastic materials. However there are plastics with practically no expansion. Details are reviewed in Chapter 2, THERMAL EXPANSION AND CONTRACTION. 

Test specimens can also be used to simulate some degree of warpage. Figure 5-8 compares unreinforced and reinforced glass fiber-TS polyester flexural-type specimens at different temperatures in a droop test (with a center support), sag test (end supports), and an expansion test (bolted at three points). The study for this particular test is conducted at various temperatures. 

In order to allow for the removal of the tube bundle and for considerable expansion of the tubes, a floating head exchanger is used, as shown in Figure 9.63. In this arrangement one tube plate is fixed as before, but the second is bolted to a floating head cover so that the tube bundle can move relative to the shell. This floating tube sheet is clamped... 

The dimensions of typical standard saddle designs are given in Figure 13.26. To take up any thermal expansion of the vessel, such as that in heat exchangers, the anchor bolt holes in one saddle can be slotted. 

ANCHOR BOLTS AS REQUIRED WOOD CANT SECURED WITH EXPANSION ANCHORS OR BOLT"IN CONCRETE CANT-... 

Lateral Expansion Requirements. Other carbon and low alloy steels having specified minimum tensile strengths equal to or greater than 656 MPa (95 ksi), all bolting materials, and all high alloy steels (P-Nos. 6, 7, and 8) shall have a lateral expansion opposite the notch of not less than 0.38 mm (0.015 in.) for all specimen sizes. The lateral expansion is the increase in width of the broken impact specimen over that of the unbroken specimen measured on the compression side, parallel to the line constituting the bottom of the V-notch (see ASTM A 370). 

Post-installed bolts will be required at times for attachment of equipment which may be subjected to large accelerations during a blast. Expansion anchors should be avoided for most blast design applications unless the load levels are low. Typically "wedge" type anchors are qualified for dynamic loads although most of these ratings are for vibratory loads and are based on cyclic tests at low stress levels. These should only be used where ultimate loads are less than the rated capacity with a margin of safely. Epoxy anchors have shown excellent dynamic capacity and may be considered for critical applications. 

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