Capacity, jack

This chapter is organized into sections on loadings, pile structures, gravity platforms, anchor uplift capacity, jack-up platforms, and hydraulic filled islands. 

Mode of operation Generic type Feed condition Specific dryer types Jack- eted Suitable for heat-sensitive materials Suitable for vacuum service Retention or cycle time Heat transfer method Capacity Typical evaporation capacity... 

Many common larger hand tools have uses in the fire service. Automotive jacks and high-lift jacks are used in vehicle rescue to stabilize cars and trucks. Sledgehammers are used in forcible entry as well as in other applications. Tools such as axes and ladders have obvious uses in the fire service, although the versions of these tools used for fire service are typically heavier or have greater capacity than domestic models. For example, fire service ladders have much greater capac-... 

Because of the size of organic dairy, hard cheese production is primarily accomplished through small family-owned cheese plants, which have the size and capacity to segregate the milk and produce a fine cheese. Many cheeses are produced organically mild and sharp Cheddar, low-fat cheeses, farmhouse cheeses, Colby, Monterey Jack, Pepper Jack, Feta, Mozzarella, Provolone, Parmesan and Romano, to name a few. 

Legend holds that Joseph of Arimathea also gave the Red Cross device to Prince Caradoc in his capacity of Defender of the Faith in Britain. From this, the Red or Rose Cross then became the device of the Christian flag of the British Church. It now dominates a St Andrew s Cross on the Union Jack. 

Jacking systems Custom designed hydraulic or mechanical system for high capacity special lifts. as specified... 

Most jack-up rigs are supported on individual pads or spud cans with 12-16 m diameter as shown in Figure 10.50. The base is often enlarged in order to increase the bearing capacity. The typical load in each leg can be up to 45 MN or more. The main limitation of this type of foundation is the low bearing capacity in very soft soil and the risk of... 

The second step of computation takes into account the influence of the weaker layer on the bearing capacity of the hard layer. The computations are based on assumptions (l)-(4) using Meyerhof and Hanna s methods as described in Hanna and Meyerhof (1980) or Meyerhof and Hanna (1978), depending on the soil characteristics. Examples of prediction results for a jack-up platform operating in the Baltic Sea are presented in Figure 10.55. 

Table 5.3 presents capacities of different modules. The AFR can be used over temperature and pressure ranges of -60 to 200 °C and 0-18 bar, respectively. The glass and ceramic construction eliminates contamination and corrosion in most cases. These are in a way similar to plate heat exchangers. The volumetric heat transfer coefficient is about 1.5 MW/m -K, which is about 1000 times higher than that in the jacketed vessels. Likewise the estimated overall mass-transfer coefficient between the phases for liquid-liquid systems is about 2 0 s which is more than 100 times those in a jacked vessel [29]. The... 

Osterberg (1984) developed a method that reduces the cost of conducting high capacity static load tests, in particular for the drilled shafts, as shown in Figure 11.6. Once the concrete is in place, the operator pumps hydraulic fluid into the jack and keeps track of both pressure and volume. The jack expands and pushes up on the shaft. A dial gauge measures this movement, from which a plot of side friction capacity versus axial movement can be obtained. The devise also includes a telltale rod that extends from the bottom of the pancake jack to the ground surface. It measures the downward movement at the bottom, and thus produces a plot of toe-bearing pressure versus axial movement. 

Two hinged steel joints were installed, one at each end of the specimens. The axial compression load was applied load-controlled via a concrete cross-beam by two hydraulic jacks of 75 kN capacity each. In order to protect the load-bearing setup and also prevent failure at joint positions, stone wool blocks were used to insulate the joints for a distance of up to 300 mm from the specimen ends (see Figure 6.26). The mechanical loading process was the same for all the specimens. 

A jack may have enough capacity to support a load, but the surface or structure that it sets on or bears against may not have enough capacity. For example, a jack placed on the ground may sink when fully loaded. A lifted object may not withstand the load and fail by bending, breaking or puncture. 

Specimens were tested in a self-reacting steel loading frame. An additional clamping system was added to the frame to hold the specimen at the top and bottom of the column and at the tip of the beam to apply the load of the hydraulic jack, as shown in Fig. 13.12. Two hydraulic jacks were used to apply the loads jack (A) of 30 ton capacity at the top of the colunrn for the axial load (maintained constant) and jack (B) of 10 ton capacity at the tip of the beam for cyclic loading on the beam, see Fig. 13.13. 

All lift slab operations should be designed by an engineer, and plans should be included with the instructions on proper methods of construction. All jacks should be labeled with their rated capacities, and should be capable of lifting at leasttwo-and-one-half times the load being lifted. Jacks should have a safety device that allows them to stop and support the weight if the load becomes too great to lift or if the jack malfunctions. 

Jacks and verticai supports shaii be positioned in such a manner that the ioads do not exceed the rated capacity of the jacks. 

The rated capacity of a jack should be stamped on the body of the jack and this capacity must not be exceeded. 

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