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  1. [11]
    سيد صلاح الصاوى
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    مشرف متميز
    الصورة الرمزية سيد صلاح الصاوى


    تاريخ التسجيل: Aug 2008
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    What are the correct standards for stainless steel?

    The most common current European standards for stainless steel are:
    EN 10088-1
    List of stainless steels

    EN 10088-2
    Technical delivery conditions for sheet/plate and strip for corrosion resisting steels for general purposes
    Chemical Composition
    Properties of Ferritic Steels
    Properties of Martensitic Steels
    Properties of Austenitic Steels
    Properties of Duplex Steels
    Properties of PH Steels
    EN 10088-3
    Technical delivery conditions for semi-finished products, bars, rods, wire, sections and bright products for corrosion resisting steels for general purposes
    All Products
    Chemical Composition
    Standard Products
    Properties of Ferritic Steels
    Properties of Martensitic Steels
    Properties of Austenitic Steels
    Properties of Duplex Steels
    Properties of PH Steels
    Bright Bars
    Properties of Ferritic Steels
    Properties of Martensitic Steels
    Properties of Austenitic Steels
    Properties of Duplex Steels
    Properties of PH Steels
    EN 10095
    Heat resisting steels and nickel alloys
    Chemical Composition
    Ambient Temperature Properties
    EN 10028-7
    Flat products made of steels for pressure purposes – Stainless steels
    Elevated Temperature Properties
    EN 10296-2
    Welded circular steel tubes for mechanical and general engineering purposes – Technical delivery conditions – Stainless steel
    Chemical Composition
    Mechanical Properties
    Tolerances
    EN 10297-2
    Seamless circular steel tubes for mechanical and general engineering purposes – Technical delivery conditions – Stainless steel
    Chemical Composition
    Mechanical Properties
    Tolerances
    EN 10216-5
    Seamless steel tubes for pressure purposes – Technical delivery conditions – Stainless steel tubes
    Chemical CompositionEN 10217-7
    Welded steel tubes for pressure purposes – Technical delivery conditions – Stainless steel tubes
    Chemical Composition
    Mechanical Properties
    These standards have replaced the old national standards and users are encouraged to use them. However, it is clear that the old standards are still used, not least because many existing drawings and company specifications refer to them. Therefore, it is still possible to come across standards such as:
    BS 1449 and BS1501 for flat products
    BS 970 for long products
    The US standards such as ASTM and ASME are very important and will never be replaced. Common standards are:
    Standard Number
    Title
    Relevant Technical Information
    ASTM A240
    Chromium and chromium-nickel stainless steel plate, sheet and strip for pressure vessels
    Chemical Composition Austenitic Steels
    Chemical Composition Ferritic Steels
    Chemical Composition Martensitic Steels
    Chemical Composition Duplex Steels
    Chemical Composition PH Steels

    ASTM A276
    Standard Specification for Stainless Steel Bars and Shapes
    Chemical Composition Austenitic Steels
    Chemical Composition Ferritic Steels
    Chemical Composition Martensitic Steels
    Chemical Composition Duplex Steels
    Chemical Composition PH Steels
    ASTM A312
    Standard Specification for Seamless and Welded Austenitic Stainless Steel Pipes
    Chemical Composition Austenitic Steels
    Chemical Composition Ferritic Steels
    Chemical Composition Martensitic Steels
    Chemical Composition Duplex Steels
    Chemical Composition PH Steels

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  2. [12]
    المهندس عبدالله
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    عضو فعال


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    لماذا لا يصدأ ستانليس ستيييل؟

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  3. [13]
    سيد صلاح الصاوى
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    الصورة الرمزية سيد صلاح الصاوى


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    Is stainless steel non-magnetic?

    It is commonly stated that “stainless steel is non-magnetic”. This is not strictly true and the real situation is rather more complicated. The degree of magnetic response or magnetic permeability is derived from the microstructure of the steel. A totally non-magnetic material has a magnetic permeability of 1. Austenitic structures are totally non-magnetic and so a 100% austenitic stainless steel would have a permeability of 1. In practice this is not achieved. There is always a small amount of ferrite and/or martensite in the steel and so permeability values are always above 1. Typical values for standard austenitic stainless steels can be in the order of 1.05 – 1.1. See Composition effects on the magnetic permeability of austenitic stainless steels
    It is possible for the magnetic permeability of austenitic steels to be changed during processing. For example, cold work and welding are liable to increase the amount of martensite and ferrite respectively in the steel. A familiar example is in a stainless steel sink where the flat drainer has little magnetic response whereas the pressed bowl has a higher response due to the formation of martensite particularly in the corners.
    In practical terms, austenitic stainless steels are used for “non-magnetic” applications, for example magnetic resonance imaging (MRI). In these cases, it is often necessary to agree a maximum magnetic permeability between customer and supplier. It can be as low as 1.004.
    Martensitic, ferritic, duplex and precipitation hardening steels are magnetic.

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  4. [14]
    سيد صلاح الصاوى
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    الصورة الرمزية سيد صلاح الصاوى


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    Can I use stainless steel at low temperatures?

    Austenitic stainless steels are extensively used for service down to as low as liquid helium temperature (-269 deg C). This is largely due to the lack of a clearly defined transition from ductile to brittle fracture in impact toughness testing.
    Toughness is measured by impacting a small sample with a swinging hammer. The distance which the hammer swings after impact is a measure of the toughness. The shorter the distance, the tougher the steel as the energy of the hammer is absorbed by the sample. Toughness is measured in Joules (J). Minimum values of toughness are specified for different applications. A value of 40 J is regarded as reasonable for most service conditions.
    Steels with ferritic or martensitic structures show a sudden change from ductile (safe) to brittle (unsafe) fracture over a small temperature difference. Even the best of these steels show this behaviour at temperatures higher than -100 deg C and in many cases only just below zero.
    In contrast austenitic steels only show a gradual fall in the impact toughness value and are still well above 100 J at -196 deg C. See Selection of stainless steels for cryogenic applications.
    Another factor in affecting the choice of steel at low temperature is the ability to resist transformation from austenite to martensite. This factor is discussed in more detail in Composition effects on the magnetic permeability of austenitic stainless steels.

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  5. [15]
    سيد صلاح الصاوى
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    الصورة الرمزية سيد صلاح الصاوى


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    Can I use stainless steel at high temperatures?

    Various types of stainless steel are used across the whole temperature range from ambient to 1100 deg C. The choice of grade depends on several factors:
    1. Maximum temperature of operation
    2. Time at temperature, cyclic nature of process
    3. Type of atmosphere, oxidising , reducing, sulphidising, carburising.
    4. Strength requirement
    In the European standards, a distinction is made between stainless steels and heat-resisting steels. However, this distinction is often blurred and it is useful to consider them as one range of steels.
    Increasing amounts of Chromium and silicon impart greater oxidation resistance. Increasing amounts of Nickel impart greater carburisation resistance.

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  6. [16]
    سيد صلاح الصاوى
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    How do I choose which stainless steel to use?

    Most decisions about which steel to use are based on a combination of the following factors:
    1. What is the corrosive environment? – Atmospheric, water, concentration of particular chemicals, chloride *******, presence of acid.
    2. What is the temperature of operation? – High temperatures usually accelerate corrosion rates and therefore indicate a higher grade. Low temperatures will require a tough austenitic steel.
    3. What strength is required? – Higher strength can be obtained from the austenitic, duplex, martensitic and PH steels. Other processes such as welding and forming often influence which of these is most suitable. For example, high strength austenitic steels produced by work hardening would not be suitable where welding was necessary as the process would soften the steel.
    4. What welding will be carried out? - Austenitic steels are generally more weldable than the other types. Ferritic steels are weldable in thin sections. Duplex steels require more care than austenitic steels but are now regarded as fully weldable. Martensitic and PH grades are less weldable.
    5. What degree of forming is required to make the component? – Austenitic steels are the most formable of all the types being able to undergo a high degree of deep drawing or stretch forming. Generally, ferritic steels are not as formable but can still be capable of producing quite intricate shapes. Duplex, martensitic and PH grades are not particularly formable.
    6. What product form is required? – Not all grades are available in all product forms and sizes, for example sheet, bar, tube. In general, the austenitic steels are available in all product forms over a wide range of dimensions. Ferritics are more likely to be in sheet form than bar. For martensitic steels, the reverse is true.
    7. What are the customer’s expectations of the performance of the material? – This is an important consideration often missed in the selection process. Particularly, what are the aesthetic requirements as compared to the structural requirements? Design life is sometimes specified but is very difficult to guarantee.
    8. There may also be special requirements such as non-magnetic properties to take into account.
    9. It must also be borne in mind that steel type alone is not the only factor in material selection. Surface finish is at least as important in many applications, particularly where there is a strong aesthetic component. See Importance of Surface Finish.
    10. Availability. There may be a perfectly correct technical choice of material which cannot be implemented because it is not available in the time required.
    11. Cost. Sometimes the correct technical option is not finally chosen on cost grounds alone. However, it is important to assess cost on the correct basis. Many stainless steel applications are shown to be advantageous on a life cycle cost basis rather than initial cost. See Life Cycle Costing.
    The final choice will almost certainly be in the hands of a specialist but their task can be helped by gathering as much information about the above factors. Missing information is sometimes the difference between a successful and unsuccessful application. See also General principles for selection of stainless steels

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  7. [17]
    سيد صلاح الصاوى
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    الصورة الرمزية سيد صلاح الصاوى


    تاريخ التسجيل: Aug 2008
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    Special Grades of Stainless Steel - Where to Find Them
    Having decided that you want to use stainless steel, it is usually quite straightforward to find the standard grades like 304/304L or 316/316L. The BSSA Find a Supplier guide will help you with the standard grades.

    For the more unusual grades, the user is directed to:

    Special Grades Supplied by BSSA Companies

    NOTE. THIS SPREADSHEET CONTAINS HYPERLINKS. USERS ARE ADVISED NOT TO USE THE SORT FUNCTIONALITY AS THERE IS A KNOWN "BUG" IN EXCEL WHICH SCRAMBLES HYPERLINKS WHEN SORTING.

    This is an initial attempt to provide information on special grades. It is recognised that there are some obvious "holes" in the data. However, on the assumption that "something" is better than nothing, the available data is being published now. It is planned that more data will be added soon.

    Categories of steel covered in the document include:


    Steel Type Typical Grades
    Ferritic 1.4003, 1.4016,1.4509, 1.4512
    Martensitic 1.4000, 1.4021, 1.4028, 1.4057, 1.4112
    Austenitic 1.4311, 1.4406, 1.4432, 1.4435, 1.4436, 1.4439, 1.4539, 1.4547
    Ferritic Heat Resisting 1.4713, 1.4742, 1.4762
    Austenitic Heat Resisting 1.4818, 1.4828, 1.4833, 1.4835, 1.4841, 1.4845
    Duplex 1.4162, 1.4362, 1.4462, 1.4410, 1.4501, 1.4507


    If you cannot find what you are looking for, please contact the Stainless Steel Advisory Service.

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  8. [18]
    طــارق _ بــلال
    طــارق _ بــلال غير متواجد حالياً
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    الصورة الرمزية طــارق _ بــلال


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    جزاك الله الف خير أخي سيد صلاح الصاوي وجعل هذا المجهود في ميزان حسناتك

    نريد منك أخي طرق عملية بسيطة للتعرف على جودة الاستانلس ستيل بطريقة سهلة بسيطة غير معقدة

    للشخص البسيط مثلي الذي يتعامل مع منتجات الاستانلس ستيل مثل الأواني والدرابزينات الحديثة وتلبيس الأعمدة و الجدران
    كيف أعرف إن كان ستيل جيد أو قليل الجودة
    وجزاكم الله خيرا

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    فرسان بالنهار
    رهبان بالليل
    لا يأكلون إلا بثمن
    ولا يدخلون إلا بسلام
    ويجبرون من يحاربهم على أن يقاتلهم حتى يأتون عليه


    هكذا كنا وسنعود إن شاء الله


  9. [19]
    gadoo20042004
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    الصورة الرمزية gadoo20042004


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    مشكوووووووووووووووووووور

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    EnG. TaMeR DaHdOuH
    Port said shipyard
    Suez Canal authority


  10. [20]
    hussam yusuf
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    اللهم اغفر له ولوالديه وللمسلمين اجمعين يارب
    طلب بسيط يا هندسه المعلومات دى كلها مش ممكن تنزلها فى فايل بى دى اف ؟؟

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