วันอาทิตย์ที่ 27 ธันวาคม พ.ศ. 2552

ฉนวนสำหรับงานเย็น cryogenic

ใครจะรู้ว่านวตกรรมล่าสุด มีการนำฉนวนโฟม Elastomeric foam มาใช้กับงานเย็นที่อุณหภูมิต่ำถึง -196 องศาเซลเซียส โดยทั่วไปนิยมใช้ พอลิยูรี่เธน หรือ foam glass
แต่ฉนวนแบบเก่าที่ใบ้กันอยู่มักมีปัญหา under insulation corrosion, UIC

วันพุธที่ 9 ธันวาคม พ.ศ. 2552

FESI : Acoustic insulation

ได้พบเนื้อหา เกี่ยวกับการทำงานเกี่ยวกับการลดเสียงในสถานที่ต่างๆ ซึ่งเป็นมาตรฐานของทางยุโรป น่าสนใจมากหาลิงค์ และอ่านได้ที่


http://www.fesi.eu/Page.aspx?pageType=NewsItem&pageID=270



Acoustic Solutions: A European Perspective

By Rennecke Hans-Joachim



Increasing population density and mobility, and mechanization of workplaces, households, and leisure activities, have resulted in increased general noise exposure for most people. The consequences for many are concentration and sleep disturbances, noise-induced hearing loss (noise deafness), and damage to the nervous system in the form of stomach, heart, and circulatory problems. According to statistics from the European Agency for Safety and Health at Work, approximately 22.5 million people in Europe suffered from hearing impairment due to noise in 2001, and about 2 million were considered extremely deaf. The costs of hearing impairment have been estimated at EUR 78 billion per year. Noise deafness is regarded as the most important and most recognized occupational disease, predominantly affecting men who work in manufacturing, construction, and transportation.



The general increase in exposure to noise has raised interest in the issue of noise protection and acoustic problems. The Acoustic Commission of the European Federation of Associations of Insulation Companies (Fédération Européenne des Syndicats d’ Entreprises d’Isolation—known as FESI) deals with these problems and assists its members with regard to acoustics and noise protection by providing information, including a series of six documents that address noise and noise protection. The documents can be used as a reference by planners, craftsmen, and contractors, but they are also applicable for training and studies. They provide detailed information about materials and systems and help users understand, evaluate, and solve acoustic problems. The idea behind the documents is to form a bridge between international directives and standards and practice-oriented application.



Document A2:

Basics of Acoustics

Acoustics is the science of sound and its influence on human beings. Document A2 deals with physical and physiological basics such as origination, propagation, and sensation of noise. The simple calculation with sound levels, representation of noise weighting, and evaluation criteria forms the basis of acoustic planning and implementation of effective noise protection (see Figure 1). The range of audibility to the human ear and the sensation and effect of different noise situations are shown in Figure 2.



Sound propagation in air, solids, and liquids—i.e., airborne, structure-borne, and water-borne sound—as well as description values for frequency, sound velocity, and wave length for sound events in these media are described in detail. Tables provide necessary material data and numerical values. Noise characteristics such as complex total sound, tone, and bang are comprehensively explained, as they are the basis of the physiological time, frequency, and nuisance weighting of noise. Explanations are provided for the following noise description values:

_ Sound pressure and sound pressure level

_ Sound velocity and sound velocity level

_ Sound intensity and sound intensity level

_ Sound power and sound power level



The connections between these values also are explained, as is the level arithmetic—i.e., adding, subtracting, and the space and time averaging of sound levels.



Document A3:

Product Characteristics—Acoustic Insulation, Absorption, Attenuation

Materials, their characteristics, and their acoustic effects are the subjects of Document A3. Acoustic insulation, attenuation (absorption) properties of materials, systems, and special constructions are presented and discussed. The international character of the FESI Acoustic Commission guarantees that products, systems, and materials common in Europe are considered. Sound insulation and sound attenuation of airborne and structure-borne sound, their measurement in the laboratory, and the handling of the single values Rw and R'w are comprehensively explained using figures and examples. Simple calculations for single systems (plane walls or pipes) enable rough estimation of the acoustic insulation of corresponding monolithic systems like brickwork, concrete walls and ceilings, or sheet-metal constructions. Weaknesses of material and system are taken into consideration. Information about “double systems” (basic walls with insulation) and absorbent insulations (suspended ceilings) is important for contractors in the room and building acoustics industry. The effects of materials and dimensions, resonances, and coupling of single layers with each other are described. Calculations and theoretical considerations are completed and supported by numerous measured values taken from standards, laboratory tests, and literature, providing a summary.



Document A4:

Acoustics in Buildings

Document A4 describes sound transmission in buildings, noise protection between rooms and against outdoor noise, as well as problems of ventilation and other operating noises. Consulting engineers and contractors get useful hints for the correct execution of noise-protection measures to avoid possible sources of defect and to determine the effectiveness of noise-control measures. One precondition for the design and dimensioning of noise protection with regard to building acoustics is knowledge of sound transmission paths (airborne, structure-borne, and impact sound). Document A4 gives examples for sound transmission between rooms through the building structure, as well as along and through technical devices (air conditioning). Simple calculation formulae and given loss factors are provided to enable users to estimate insulation and sound-improvement indices. Diagrams provide information about the influence of leak points such as venting slots and keyholes on the acoustic insulation of walls, doors, and enclosures. Examples of systems and comprehensive tables with insulation coefficients of approved constructions also are included. Tables with detailed information and classifications of door and window constructions relating to sound insulation provide useful tips.



Document A5:

Acoustics in Rooms

Apart from protection against noise, acoustics also involves communication and information so that people in a room can hear and understand what is being said. Document A5 describes acoustic characteristics of rooms and how to influence these characteristics. The document also explains the physical quantity “reverberation time T” as well as “indices for the determination of speech intelligibility:”

_ Articulation index (AI)

_ Sound interference level (SIL)

_ Percentage articulation loss of consonants (%ALCons)

_ Speech transmission index or rapid speech transmission index (STI, RASTI)



The validity of these quantities, correlations, and proportions, as well as numerous requirements and recommendations, facilitate the weighting of speech intelligibility in different rooms. Subjective factors such as distinctness, spaciousness, harmony, and steadiness also are discussed. Especially helpful is the table “Key parameters suggested for different types of rooms,” which states by which quantities different types of rooms must be weighted. Subsequent chapters of the document provide details for the treatment and furnishing of rooms. Simple calculations of sound propagation in rooms of different dimensions (cubic, flat, or long) are provided, along with comments regarding natural frequencies, sound diffusion, and acoustic phenomena like echoes/flutter echoes. Noise protection measures and their materials and position in the room are described so the best possible effect will be achieved.



Document A6:

Industrial Acoustics

As EU rules with regard to noise at the workplace and industrial plants’ effects on surrounding neighbourhoods have become stricter, Document A6 is of particular importance. Contractors get significant information on the sound and vibration effects of machines and plant components, sound propagation in workshops or toward adjacent residents, and the execution of effective sound protection. Materials, systems, their dimensioning and effect, sources of defects, and problematic situations are also discussed. Document A6 first deals with sound propagation in free field; in rooms; and in ducts, pipes, and air-conditioning systems. It explains how the distance between sound source and receiver, distribution of the radiated sound energy, acoustic insulation and attenuation on the propagation path, and additional noise sources disturb the “receiver”—e.g., at the workplace or in the neighbourhood of a plant. Simple calculations, tables with sound insulation and attenuation, and data of noise sources—e.g., in pipes and air-conditioning systems—enable estimation of disturbing noise and its reduction. A chapter on noise control discusses measures at the source or the point of origin, at the propagation path, and at the receiver corresponding to the model source, path, and receiver. Measures at the source and on the propagation path have first priority. The chapter describes the function and construction of silencers, sound hoods, and sound screens. Their effect can be estimated by a simple function, or it can be taken from corresponding tables. The effect of a sound hood is determined by:

_ Structure and weight per unit area of the hood wall

_ Portion of free openings in case of penetrations, or openings for material supply and removal, and

_ Possible vibration transmission by the foundation

Table 9, “Orienting construction characteristics for the enclosure groups,” lists examples and minimum requirements to comply with desired insertion losses. Users get the desired information at a glance without time-consuming calculations. Absorbent wall or ceiling linings prevent or reduce sound reflections without influencing the direct sound. The effect of this noise protection measure depends not only on the material and its dimensions, but also on the position with regard to noise source and receiver. A figure is provided illustrating such a situation (see Figure 3). The effect of the measure can be estimated with the corresponding functions.



Document A7:

Guidance through FESI Documents A2 through A6

Document A7, currently in progress, will be a reference for users of the other documents and includes all terms, rules, and body of directives. The chapter “Noise Control” references significant chapters of aforementioned acoustic documents, standards, and recommendations for further reading on dimension noise protection measures. The chapter “Measurements” describes how to prove the effectiveness of such measures, appropriate procedures and the use of the body of directives (regulations, standards, and recommendations) to determine sound emissions, as well as frequency dependent weighting and evaluation. In short, document A7 will provide a framework for acoustical design and problem solving.



Future Projects

Apart from completion of Document A7, the Acoustic Commission is dealing with the subject of acoustic comfort. The preparation of Document A5 with the acoustic evaluation of rooms according to their use (e.g., restaurants, classrooms, multi-purpose rooms) and terms like speech intelligibility and distinctness revealed that this subject has not been sufficiently considered in Europe. Thus, the Acoustic Commission first will verify the situation in Europe through use of a survey in the member countries, which will be supplemented by data of research and science, if necessary. Based on the results, recommendations will be given to standard organizations, working groups, and FESI members to enable them to design and implement noise protection measures. Documents A2 through A6 in English and the bilingual edition (German/English) can be downloaded from the FESI

website.



This article appeared in the December 2008 issue of Insulation Outlook.

Author Rennecke Hans-Joachim

Hans-Joachim Rennecke is Chairman of the FESI Acoustic Commission and Head of KAEFER Department Corporate Technology & Research/Acoustics at KAEFER Isoliertechnik GmbH & Co. KG. He has 30 years of experience with acoustic insulation in the fields of industry, shipbuilding, and room and building acoustics. He can be contacted at hj.rennecke@kaefer.com.




FESI thermal insulation technical article : Very good





ท่านสามารถเข้าไปลิงค์ได้ที่นี่ และ มีไฟล์ให้ดาวน์โหลด ขอบอกว่า เป็นบทความ ที่ดีมากๆ ถ้าคิดจะหากินด้านฉนวน http://www.fesi.eu/Page.aspx?pageType=page&pageID=235 1. Insulation work on industrial plant – ancilliary work – calculation O9/2008 approved as a current document part 1 part 2 This paper proposes a measurement method for pipes and equipment that are/are to be insulated. It provides an inventory of calculation bases for the measurement of all elements of which the insulation of industrial plant consists including: - Pipes and ducts - Distributors and collectors - Appliances, vessels and columns - Caps and dome ends 2. Rules for carrying out thermal insulation work – hot Under revision – combined with no 3 under review 3. Rules for carrying out thermal insulation work – cold Under revision – combined with no 2 under review 4. Working manual : system for measurement and recording of industrial insulation cladding 02/1995 under review This manual creates a system of measurement for sheet metal preparation and assembly for cladding pipes, fittings, vessels and tanks in industrial installations. 5. Problems with associated with the warranty of specified surface temperatures 09/2008 approved as a current document This paper highlights the problems associated with warranting surface temperatures with theoretical calculations as the surface temperature is dependant on a number of physical parameters that cannot be calculated or estimated with the necessary degree of certainty. 6. High profitability through ecologically based insulation thicknesses 09/2008 approved as a current document This paper shows that if insulation thicknesses are increased beyond the optimum ‘economic thickness’ to meet an ‘ecological’ standard, the pay back period is only marginally increased particularly on larger bore pipework. 7. Heat insulation of refrigerated premises and buildings – technical clauses 09/2008 approved as a current document This paper provides technical clauses that define the heat insulation works of refrigerated premises and buildings. They give instructions concerning the materials and products required and corresponding rules for installation. 8. Principles of cold insulation 09/2008 approved as a current document This paper discusses the prime requirement to minimise risk of moisture entering cold insulation systems and how to achieve this by use of an efficient vapour retarder and closed cell insulation effectively bonded together. 9. Prevention of corrosion on insulation cladding 09/2008 approved as a current document This paper explains the nature of and mechanism for metal corrosion. It considers the relative corrosion risks for the various metal traditionally used for insulation claddings and their fixings and considers strategies to minimise corrosion. 10. Corrosion under insulation: Problems and solutions 09/2008 approved as a current document This paper considers the factors that can cause the corrosion under insulation that can lurk undetected with disastrous consequences. It explains separately how the designer and the insulation contractor can play their part in preventing this. It goes on to give practical guidance for effective insulation work and finally provides pointers to what the operator should consider to control deterioration of the insulation system. 11. Problems of thermal stress in metal reinforcements of large dimensional objects with elevated service temperatures 09/2008 approved as a current document This paper explains the problems caused by the reinforcing stiffeners required on hot large dimensioned ducts particularly found in power stations. The temperature differentials between the inner and outer edges of the stiffeners can lead to cracking of welded seams. It explains the considerations needed to calculate the appropriate insulation thickness to maintain the maximum admissible temperature differentials. 12. Design of cold insulation to prevent formation of condensation 09/2008 approved as a current document The most frequent reason for cold insulation is to prevent condensation on the insulation cladding surface. The paper provides a checklist of the information needed to design effective cold insulation systems whether provided by client or contractor. 13. Preventive fire protection in buildings Part 1 Insulation works / executive directions Part 2 Guidelines for executions

วันศุกร์ที่ 4 ธันวาคม พ.ศ. 2552

PTT's plan with projects

PTT suspends merger plans Group awaits outcome of Map Ta Phut case A planned merger of four PTT Group petrochemical and refining units has been delayed pending a court settlement on the ongoing Map Ta Phut dispute, a senior executive says. The merger has been delayed until the court outlines clear environmental enforcement guidelines for 76 suspended industrial projects, worth about 400 billion baht, in Rayong’s Map Ta Phut Industrial Estate, said Prajya Phinyawat, chief operating officer of PTT’s downstream petroleum business group. Of the 76 suspended projects, 25 ventures, worth about 130 billion baht in total, belong to PTT and its affiliates. PTT has been studying the possible merger of PTT Chemical Plc (PTTCH), IRPC Plc, PTT Aromatics and Aromatics and Refining Plc (PTTAR) and Thai Oil Plc (TOP). The plan, which was originally to be finalised in October, was pushed back to the year-end. But Mr Prajya said the merger would now not be concluded until the court sets clear compliance guidelines for the projects. “How can we decide which formula is most suitable for the merger until we know what is going to happen with their operations [once the verdict is made]?” he said yesterday. “The merger will proceed immediately after we know what we have to do to comply with the court’s order.” PTTCH, meanwhile, has been in talks to acquire petrochemical projects in neighbouring countries, said president and CEO Veerasak Kositpaisal. Negotiations with petrochemical manufacturers in Southeast Asia are expected to conclude next year. The company has the capacity to raise up to 60 billion baht in funds to finance investments over the next five years, he said. Asean will integrate into a single production base by eliminating tariffs on petrochemical products traded within the region next year. Asean market integration will pave the way for better access for PTTCH products to markets such as Indonesia, the Philippines, Malaysia and Vietnam. Mr Veerasak said acquiring existing assets in Asean was appropriate for PTTCH to integrate its operations as key petrochemical products are expected to swell when new capacity, mainly from the Middle East and China, come online starting next year. At the same time, PTTCH has prepared a contingency plan in case PTT’s sixth gas-separation plant – one of the suspended projects in Map Ta Phut – has to be delayed beyond its scheduled operational target of the first quarter next year. The $780-million gas-separation plant is considered vital to the operation of PTTCH’s cracker plant which is targeted to start commissioning in late December, he said. PTT’s chief financial officer Tevin Vongvanich said if, in the worst case, the sixth gas plant cannot proceed, 300 million cubic feet per day of local supply will evaporate, forcing Thailand to import more liquefied petroleum gas. PTT projects crude oil price to move in a range of $65 to $75 per barrel in the final quarter, with Dubai crude now trading above $70, he said. The gross refining margin is expected to edge down from $1.70 a barrel in the third quarter while petrochemical prices will also weaken. “Fortunately, the spread margin has declined less than we anticipated while the demand has improved in line with the global economy,” he said. Consequently, PTT is likely to report better-than-expected profit this year, possibly higher than the 51.7 billion baht posted in 2008, but total revenue will fall below last year’s 2 trillion baht. Shares of PTT closed yesterday on the Stock Exchange of Thailand at 233 baht, down six baht, in trade worth 1.03 billion baht. PTTCH declined 1.25 baht to 70.75, in turnover worth 206.4 million baht. ฺํBY Bangkok Post 20/11/09

76 projects in Map Ta Phut with insulations

โครงการที่ ผ่านให้มีการ ทำงานต่อไปได้


1. Clean energy and product quality enhancement/Rayong Refinery

2. Gas recycling enhancement/HMC Polymers

3. Clean energy, oil vapour controlling unit installation/Star Petroleum Refining

4. Oil vapour controlling unit installation/PTT Aromatics and Refining

5. Air pollution improvement/Indorama Petroleum

6. Wastewater treatment improvement/PTT

7. Chlorine vaporiser and wet scrubber installation/Aditya Berla Chemicals (Thailand)

8. Tank relocation/Map t Tank Terminal

9. LPG/Brutene Depot-Wharf/PTT Chemical

10. Loading Arm Installation/Star Petroleum Refining

11. Petrochemical Depot-Wharf/Map Ta Phut Tank Terminal