Joints grooved

Blow-up is the localised upward movement (buckling) that can be considered as surface deformation of rigid pavements. It usually occurs at transverse joints owing to excessive expansion of the slabs during high-temperature periods. The main contributor to blow-ups is the infiltration of incompressible materials into the joints, provided the joint (groove) is sufficient. 

Minor and shallow spalling is usually treated by removing the affected area by widening the joint groove and filling it with sealant or by removing the broken area (to the required width and depth of at least 10 mm) and filling it with concrete mortar, if the depth is approximately 20 mm, or with fine concrete, if it is deeper joint sealant may also need to be replaced. 

First, the joint groove and adjacent surfaces must be thoroughly degreased with a solvent, such as acetone, that does not leave a residue. This will prevent pickup of impurities, especially carbon, before welding. The filler metal must also be handled carefully to prevent it from picking up... 

The low-pressure HRE-2 valves are novel in that ring-joint grooves are integral with the valve body, as illustrated in Fig. 8-17(b). Long bolts at the corners of the valve body hold the companion flanges the valve is replaceable with the disassembly of only one set of bolts. 

Grooved joints (Fig. 10-139) are divided into two classes, cut grooves and rolled grooves. Rolled grooves are preferred because. 

Expanding the tube into the grooved tube holes provides a stronger joint but results in greater difficulties during tube removal. 

F lge,/. joint slit groove suture, fugen, fiigen, v.t. join, unite joint add. fugenlos, a. jointless, seandess. fuglich, adv. reasonably well, easily. fUgsam, a. tractable, pliant. 

The serrated and grooved joints are used for high-pressure differentials but usually not in services exceeding 200°F as a rule. Actually these joints will withstand more than twice the push or pull on the tube as a plain joint. The serrations or grooves provide points of strength and effect a better seal against fluid leakage. 

If conditions are such as to require a duplex tube, it is quite likely that a plain end detail for the tube will not be satisfactory. Grooved or serrated joints are recommended for this type of tube, and the ends should be flared or beaded. Table 10-8 gives recommended flare or bell radii for copper-based alloys. Also see Table 10-8A. In service where galvanic corrosion or other corrosive action may take place on the outside material used in the tube, a ferrule of inside tube... 

Key seats occur in dog legs of the borehole. The drill pipes cut a groove in the wall at their dimension and when tool joints or drill collars are pulled up, the drillstring gets stuck. 

A lubricant-starved chain drive shows a brownish or rusty coloration around the joints and in the roller-bushing areas when the link is disassembled and the pin inspected. The normal highly polished surface of the pin will have deteriorated to a roughened, grooved, or galled surface that can eventually destroy the hardened surfaces of the chain parts and increase wear until the drive is completely destroyed. This also will be hue if a lubricant that does not meet the chain s technical specifications is used. 

Corrosion of steel by carbonic acid is probably the most common problem in the post-boiler section, producing pipe grooving and general metal wastage, especially in threaded joints. This form of corrosion is not self-regulating and the reaction products can produce more carbon dioxide, thus perpetuating the corrosion problem. Typically, the condensate pH level is depressed to around 5.0 to 5.5. 

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