Maximum design temperature

For all design temperatures, the maximum hardness shall be Rockwell C35 immediately under the thread roots. The hardness shall be taken on a flat area at least 3 mm ( A in) across, prepared by removing threads. No more material than necessary shall be removed to prepare the area. Hardness determination shall be made at the same frequency as tensile tests. 

Impact testing is not required if the design temperature is helow —29 C (—20 F) hut at or above —46 C (—50 F) and the maximum operating pressure of the fabricated or assembled components will not exceed 25 percent of the maximum allowable design pressure at ambient temperature and the combined longitudinal stress due to pressure, deadweight, and displacement strain (see Par. 319.2.1) does not exceed 41 MPa (6000 Ibfiin ). 

Subsection A This subsection contains the general requirements applicable to all materials and methods of construction. Design temperature and pressure are defined here, and the loadings to be considered in design are specified. For stress failure and yielding, this section of the code uses the maximum-stress theory of failure as its criterion. 

System design accommodating maximum expected pressure and temperature... 

Ensure utility temperature does not exceed runaway reaction temperature or vessel maximum design temperature... 

Application practices suggest a maximum design temperature of about 300 °F (149 °C) for babbitt, and designers will set a limit of about 50°F (28 °C) less. As temperatures increase, there is a tendency for the metal to... 

Air Temperamre Design temperature for equipment and outdoor transformers shall be 98°F. Design Temperature for the Installation of Service Equipment - Maximum Temperamre 100°F - Minimum Temperamre 60°F Design Temperamre for Calculation of the Heat Loss - Normal Daily Average 79°F. The maximum mean relative humidity is 97%. Mean relative humidity -82%... 

Maximum Allowable Working Pressure (MAWP) the maximum pressure pounds per square inch gauge permissible at the top of a completed vessel in its operating position for a specific designated temperature corresponding to the MAWP pressure. This pressure is calculated in accordance with the ASME code (Par. UG-98) [1] for all parts or elements of the vessel using closest next larger to calculated value nominal thickness (closest standard for steel... 

The maximum allowable working pressure is equal to or greater than the design pressure for a coincident design temperature. 

In this analysis the designer must consider two conditions and base the pipe design on the one that is worse. One condition is where the temperature differential is one half the difference between the maximum temperature and minimum temperature. The second condition considers the temperature differential between the maximum pipeline temperature at installation and the minimum design temperature. 

The strength of metals decreases with increasing temperature (see Chapter 7) so the maximum allowable design stress will depend on the material temperature. The design temperature at which the design stress is evaluated should be taken as the maximum working temperature of the material, with due allowance for any uncertainty involved in predicting vessel wall temperatures. 

Figure 73. Average monthly day-minimum, day-maximum and day-average temperatures at Croydon and average typical temperature range of the climate station High Holbome London Weather Centre—(design temperatures)...

Ambient temperatures (Figure 73) measured at Croydon are by and large comparable to the design temperatures at High Holborn. It can be noted that the winters of 2000 and 2001 have been somewhat colder than normal, while summers (and especially maximum temperatures reached) have been quite a bit warmer in 2002 and 2003. The difference between minimum and maximum temperatures is much larger, as in the monitored data the temperatures are not averaged over a period of more years. 

DT = design temperature MOP = maximum operating pressure MOT = maximum operating temperature 3.40% baffle cut = 40% open area is a good rule-of-... 

A natural gas (methane) pipeline is to be designed to transport the gas at a rate of 50,000 scfm. The pipe is to be 6 in. ID, and the maximum pressure that the compressors can develop is 10,000 psig. The compressor stations are to be located in the pipeline at the point at which the pressure drops to 100 psi above that at which choked flow would occur (this is the suction pressure for the compressors). If the design temperature for the pipeline is 60°F, the compressors are 60% efficient, and the compressor stations each operate with three stages and interstage cooling to 60°F, determine... 

So the multiplier must be 5°5 = 2.236, which agrees with the published datasheet value. Therefore we see that from the vendor s published ripple current temperature multipliers, we can easily deduce his designed-in maximum core temperature. 

The stress values in Table IX-1 and Table IX-4 are grouped by materials and product forms, and are for stated temperatures up to the limit provided in para. GR-2.1.2(a). Straight-line interpolation between temperatures is permissible. The temperature intended is the design temperature (see para. IP-2.1.4). Material performance factors located in Tables IX-5 are grouped by material type, material tensile or yield strength, and maximum system design pressure. Straight-line interpolation is permissible. 

P max Maximum allowable gage pressure for continuous operation of component at maximum design temperature kPa psi... 

There is an NPS 8 branch at right angles to an NPS 12 header (Fig. E-l). Both run and branch are of aluminum alloy Schedule 80 ASTM B 241 6061-T6 seamless pipe. The connection is reinforced by a ring 14 in. O.D. (measured along the run) cut from a piece of NPS 12 Schedule 80 ASTM B 241 6063-T6 seamless pipe and opened slightly to fit over the run pipe. Allowable stresses for welded construction apply in accordance with Mandatory Appendix IX, Table IX-1A, Note (28). The fillet welds have the minimum dimensions permitted in para. IP-3.4. A zero corrosion allowance is specified. What is the maximum permissible design pressure if the design temperature is -320°F ... 

Texo was determined for each case 1 - 3 in accordance with the experimental results. For each case Texo is clearly above 100°C. Because of the relationship between Texo and the production of gas, it is necessary to set the design temperature (Tmax. design) equal to TeXo (unless for example the materials of construction necessitate a lower maximum temperature, a possibility that is not considered here). 

It is possible to assume that the worst case conditions will prevail at all times, but this will probably lead to an unrealistically short lifetime. For example, the design temperature can be taken as the maximum. 

Numerous test methods are available using a variety of sample sizes and conditions. The tests provide qualitative or quantitative data on onset of temperature, reaction enthalpy, instantaneous heat production as a function of temperature, maximum temperature, and/or pressure excursions as a consequence of a runaway, and additional data useful for process design and operation. 

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