17 Boiler design pressure

Cyclic internal pressure tests were conducted over several hundreds of cycles at pressures up to and in excess of the calculated proof test pressure on two nominally ‘identical’, stainless steel type 316 flush 90 degrees pressure vessel nozzles, designed and manufactured to BS 5500. Prior to this pressure cycling, one vessel was subjected to the required proof test of 1.25 times the design pressure. Significant incremental straining was recorded in the non-proof tested vessel during cycling at all pressures above the first yeild pressure (0.336 × design pressure). For the proof tested vessel significant incremental straining was not recorded during cycling until 15 percent above the design pressure.

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Hatch Covers on Bulk Carriers: The Effect on Procurement Costs of Changes in Design Pressure

10.3940/rina.bc.2001.11 ◽

2001 ◽

Author(s):

David Byrne ◽

Keyword(s):

Bulk Carriers ◽

Design Pressure

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Thermal Hydraulic Analysis of Severe Accident in PFBR

18th International Conference on Nuclear Engineering: Volume 4, Parts A and B ◽

10.1115/icone18-29356 ◽

2010 ◽

Author(s):

K. Velusamy ◽

P. Chellapandi ◽

G. R. Raviprasan ◽

P. Selvaraj ◽

S. C. Chetal

Keyword(s):

Atmospheric Pressure ◽

Fluid Dynamic ◽

Hydraulic Modeling ◽

Severe Accident ◽

Maximum Temperature ◽

Maximum Pressure ◽

Dynamic Calculation ◽

Thermal Hydraulic Modeling ◽

Thermal Hydraulic Analysis ◽

Design Pressure

During a core disruptive accident (CDA), the amount of primary sodium that can be released to Reactor Containment Building (RCB) in Prototype Fast Breeder Reactor (PFBR) is estimated to be 350 kg/s, by a transient fluid dynamic calculation. The pressure and temperature evolutions inside RCB, due to consequent sodium fire have been estimated by a constant burning rate model, accounting for heat absorption by RCB wall, assuming RCB isolation based on area gamma monitors. The maximum pressure developed is 7000 Pa. In case RCB isolation is delayed, then the final pressure inside RCB reduces below atmospheric pressure due to cooling of RCB air. The negative pressure that can be developed is estimated by dynamic thermal hydraulic modeling of RCB air / wall to be −3500 Pa. These investigations were useful to arrive at the RCB design pressure. Following CDA, RCB is isolated for 40 days. During this period, the heat added to RCB is dissipated to atmosphere only by natural convection. Considering all the possible routes of heat addition to RCB, evolution of RCB wall temperature has been predicted using HEATING5 code. It is established that the maximum temperature in RCB wall is less than the permissible value.

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Flaw Stability Analysis of Semi-Elliptical Surface Cracks in Canisters Under the Influence of Welding Residual Stress

Volume 6B: Materials and Fabrication ◽

10.1115/pvp2016-63887 ◽

2016 ◽

Author(s):

Jinhua Shi ◽

Liwu Wei ◽

Poh-Sang Lam

Keyword(s):

Heat Treatment ◽

Residual Stress ◽

Spent Nuclear Fuel ◽

External Surface ◽

Welding Residual Stress ◽

Surface Cracks ◽

Coastal Regions ◽

Dry Storage ◽

Induced Stress ◽

Design Pressure

Many stainless steel canisters for the dry storage of spent nuclear fuel are located in coastal regions. Because the heat treatment for relieving the welding residual stress is not required during fabrication, these canisters may be susceptible to chloride induced stress corrosion cracking due to the deliquescence of chloride-bearing marine salts or dust that enter the overpack system and deposit on the canister external surface. The NDE techniques and the associated delivery system are being developed to conduct periodic inservice inspections. The acceptance standards are needed to disposition findings should flaw-like indications be found. The instability crack lengths and depths for these flaws in the form of semi-elliptical shape near the welds are determined with R6 procedure. The cracks are subject to the canister design pressure and handling loads as well as the estimated welding residual stresses.

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MEASUREMENT OF THERMAL EFFICIENCY OF HEATING BOILER WITH FURNACE WALL WATERFLOW

Vestnik Tomskogo gosudarstvennogo arkhitekturno-stroitel nogo universiteta JOURNAL of Construction and Architecture ◽

10.31675/1607-1859-2019-21-1-169-176 ◽

2019 ◽

pp. 169-176

Author(s):

A. S. Klimov ◽

R. T. Emelyanov ◽

A. F. Aleksandrov ◽

V. A. Taranov

Keyword(s):

Thermal Efficiency ◽

Lower Boundary ◽

Heating Surface ◽

Large Error ◽

Furnace Wall ◽

Temperature Fields ◽

Thermal Probe ◽

Local Coefficients ◽

Measurement Results ◽

Boiler Design

This article deals with the improvement of thermal efficiency of heating boilers with furnace wall waterflow. During one cycle in a PK-38 boiler the average level of the heat flow decreases by 25–30 %. The incident heat flux is measured with a thermal probe which, however, gives a large error in the measurement results. Experiments show that the error depends on the penetration of the thermal probe into the outer surface of thermal zone as well as on cavities in sealing the thermal probe, and different thermophysical properties of the latter and metal material of the heating surface. The accuracy of the measured parameters is affected by the thermal probe sealing. It is found that the distortion of temperature fields is more significant at the lower boundary of the thermal probe junction at frequently used sealing. Studies show that the waterflow leads to the restoration of local coefficients of thermal efficiency to the previous values. The obtained results can be used in boiler design and allow improving the measurement methods for thermal efficiency of heating boilers with furnace wall waterflow.

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Challenges of Hot Tapping Into a Sour Gas Transmission Line

Volume 1: Codes, Standards and Regulations; Design and Constructions; Environmental; GIS/Database Development; Innovative Projects and Emerging Issues ◽

10.1115/ipc2000-101 ◽

2000 ◽

Author(s):

Ray Goodfellow ◽

Rory Belanger

Keyword(s):

Transmission Line ◽

Operating Conditions ◽

New Production ◽

Line Pressure ◽

Welding Procedure ◽

Sour Service ◽

Line Temperature ◽

Procedure Development ◽

Design Pressure ◽

Sour Gas

Chevron Canada Resources recently completed a hot tap on the Simonette high-pressure sour gas transmission line near Grande Prairie, Alberta. The hot tap was required to bring on new production into the Simonette pipeline without shutting in existing production. The hot tap was completed under full line pressure and gas/condenstate flow during the winter with temperatures averaging −20°C. The design pressure of the 12 “ Gr. 359 Cat II pipeline is 9930 kPa and the line operates at 8200 kPa. The gas in the main transmission line is approximately 2% H2S and 4% CO2. The gas being brought on through the 4″ hot tap tie-in was 21% H2S and 5% CO2. At the tie-in point the transmission line temperature was 3°C. Safely welding on the pipeline under these conditions was a considerable technical challenge. In welding sour service lines it is critical that the final weld hardness be below Vickers 248 micro hardness. This can be very difficult to achieve when welding on a line transporting a quenching medium of gas and condensate. In addition, hydrogen charging of the steel from operation in sour service can lead to hydrogen embrittlement during welding. Ludwig & Associates developed the hot tap weld procedure and extensively tested the procedure to ensure that suitable weld microhardness was achievable under pipeline operating conditions. As part of the procedure development the welder who would perform the hot tap was tested repeatedly until he could confidently and successfully complete the weld. During fieldwork, the welding was rigorously monitored to ensure procedural compliance thereby minimizing the possibility of elevated hardness zones within the completed weldment. This paper will detail with the technical development of the hot tap welding procedure and the successful field implementation.

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ASESMEN KOROSI & ANALISIS RISIKO KUALITATIF PADA VERTIKAL BEJANA TEKAN

TEKNOSAINS : Jurnal Sains, Teknologi dan Informatika ◽

10.37373/tekno.v8i2.111 ◽

2021 ◽

Vol 8 (2) ◽

pp. 63-72

Author(s):

Amam Fachrur Rozie ◽

D.N Adnyana

Keyword(s):

Risk Analysis ◽

Corrosion Rate ◽

Pressure Vessel ◽

Atmospheric Corrosion ◽

Uniform Corrosion ◽

Vertical Pressure ◽

Qualitative Risk Analysis ◽

Non Destructive ◽

Design Pressure

Keselamatan dan keamanan dalam penggunaan bejana tekan sangat penting dan hal utama dalam penggunaan bejana tekan, terlebih lagi jika bejana tekan tersebut sudah melewati umur desain nya. Penelitian ini bertujuan untuk menilai kelayakan kondisi terkini dari suatu bejana tekan vertikal (vertical pressure vessel) yang telah beroperasi sejak tahun 1970 tetapi berhenti beroperasi pada tahun 2011. Pendekatan penilaian pada bejana tekan vertikal ini berbasis pada metode penilaian korosi dan risiko secara kualitatif. Selain itu juga dipergunakan metode-metode lain dalam aspek penilaian nya seperti visual inspeksi, laju korosi (corrosion rate), Non-Destructive Examination (NDE), software calculation dan analisa risiko kualitatif (qualitative risk analysis). Dari hasil observasi dan inspeksi di dapat tekanan desain (design pressure) adalah 7 kg/cm2, Temperatur desain (design temperature) adalah 61°C dengan material konstruksi adalah SA-283 Gr. C dan standard & code yang dipergunakan adalah ASME Sect. VIII Div. 1 dan API 510 serta beberapa standard & code lainnya. Dari hasil kajian dan kalkulasi di lapangan, maka didapat faktor penyebab kerusakan yang kemungkinan terjadi adalah atmospheric corrosion & uniform corrosion dengan nilai laju korosi adalah sebesar 0,127mm/yr dan tingkat risiko dari bejana tekan vertikal ini masuk dalam kategori 2D yang artinya adalah medium-high dengan maksimal umur pakai sampai usia 27 tahun untuk top head dan 24 tahun dan bottom head serta 23 tahun untuk shell. Sehingga dapat disimpulkan bahwa bejana tekan ini masih aman dan layak dipergunakan dengan batasan-batasan di atas.

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