卡通 自拍 亚洲 另类

<tbody id="bbqa4"><noscript id="bbqa4"></noscript></tbody>
  • <rp id="bbqa4"><samp id="bbqa4"></samp></rp>
    <th id="bbqa4"></th>
    1. <em id="bbqa4"></em>

    2. <button id="bbqa4"><acronym id="bbqa4"></acronym></button>
      Welcom to QINGDAO MEGATRO HOLDING CO.,LIMITED

      FAQ

      FAQ

      • Question1. How about your tower design & condition?

        MEGATRO has highly qualified and experienced structural design engineers. Apart from that MEGATRO also have exclusive tie-up with world renowned design companies and institute abroad which helps in highly precise design of the towers thereby optimizing cost reduction by over 30%.

        The tower design, which is an iterative process consists of following steps

        a) Propose a geometry of tower, member sizes etc.

        b) Work out the loads likely to be experienced by tower due to antennas, wind, earthquake, ice etc.

        c) Calculate the forces generated in each individual member of tower

        d) Check that proposed member size is suitable for the forces experienced by that member. If not, reselect suitable member size and reiterate the process till all members are confirmed to be suitable for the forces experienced by them.

        MEGATRO Towers are designed using latest software based programs taking into account various parameters such as

        Wind load conditions

        ?    Antenna loading (only for telecom tower)

        ?    Conductor load conditions

        ?    Ice load conditions

        ?    Topography factor

        ?    Dynamic effect of wind

        ?    Lights loading(only for telecom tower)

        ?    Factor of safety

        ?    Certification / Standards requirements

        Our Designs are validated by China electric power design institute and our design also accepted by international clients.

        MEGATRO Key Factors of Design concern as follow

        ?    High quality

        ?    Optimization of actual need

        ?    Should have less wind resistance and hence less foundation forces

        ?    Easy assembly and erection

        ?    Long durability

        ?    Better working platform (for telecom tower )

        ?    Dedicated independent prototype assembly units

        MEGATRO has in house facilities for:

        ?    Design of towers: We use DAP POWER, PLS and other designing software for static & dynamic analysis of the tower models.

        ?    Computerized modeling: We do 3D modeling of our towers before actual production is taken up. This modeling helps us to carry out the detailing of the tower with a very high degree of accuracy.

        ?    We have a well equipped tool room to facilitate maintenance of our dies, tools etc

        ?    We employ modern techniques of fabrication e.g. our gusset templates are computer generated to eliminate all drawing errors.

        Above in-house facilities result in following advantages to the customer:

        ?    A new design of tower, having different geometry or different loads is developed in a very short time.

        ?    The detailing of the towers has a very high level of precision, which results in fast & easy erection.

        ?    Our production is never held up due non availability of any section. Our design team is always able to recommend us an alternative for the section not available.

        Other Facilities:

        Apart from above in-house facilities, we have long term arrangements with specialised consultants for :

        ?    Soil investigations

        ?    Galvanization of fabricated tower materials

        ?    Testing of materials as per applicable standards.

        We can organize the following tests in relation to tower:

        ?    Strength of materials used

        ?    Thickness of zinc coating provided

        ?    Testing the verticality of tower using theodolites etc.

      • Question 2. How about your tower design software?

        MEGATRO is fully equipped and qualified to carry out Design Engineering services which includes:

        √ Overhead transmission line steel tower & Telecom steel tower

           Basic Design and Analysis 

        √ Shop Erection Drawings 

        √ As-Built Drawings 

        MEGATRO performs in-house design activities specializing in electrical overhead transmission &telecom tower steel works, which include wind and earthquake loading, static analysis, stress analysis by finite element methods and fatigue. 

        Transmission line & Telecom tower & Monopole design software

        Weisman (Canada)

        Telecom tower analysis 

        I-Tower (Indian IMI)

        Transmission line Tower Design 

        PLS-Tower (USA) 

        Transmission line &Telecom Tower Design

        SAP &TMA (China)

        Transmission line Tower Design

        Dao power 

        Transmission line Tower Design

      • Question 3. Which specifications for the telecom tower must be specified by tower buyer/ Communication system designer?

        The buyer must decide/specify the following parameters, before asking for an offer from tower supplier. All the following factors will affect the cost of the tower.

        a) Height: Height of tower must be determined by “Line of sight survey”. For telecom tower, if height of tower is less than required height, then communication will not take place. If height of tower is more then required height, then signals will overshoot the desired area and create interference and other complications. For power transmission line tower, if tower height less or more than required height, then influenced conductor and affects final power transmission.
        While deciding the height of tower, availability of clear space around tower site should be kept in mind. There should not be any hazardous installation e.g electric pole. inhabited building within falling distance of tower.
        If tower is being installed on a roof top then structural strength of building will be controlling factor, moreover, the cost of a tower varies approximately as square of its height.

        b) Expected loading on tower – Amount of load on tower will determine whether it is light weight, standard or heavy duty etc. Normally the factors, which constitute major portion of load are
        i) Survival wind speed - Doubling the survival wind speed will increase the forces acting on tower 4 times. The metrological data of any area provides the maximum wind speed, which has occurred in that area during last 10 years or 50 years .
        ii) No of antennas,or cross-arm quantity – their physical sizes, weights, levels on tower and firing angles.
        iii) Spare structural capacity for additional loading of antennas in future.
        iv) Appurtenances required on tower i.e.
        a) Platforms, with /without railing, internal/external, levels on tower.
        b) Climbing ladder with safety loops, monkey ladder / staircase.
        c) Cable ladder – width required to accommodate required number of cables.
        d) Safety climbing devices – e.g Fall Arrestor, if required any.

        c) Twist and Sway permitted – when wind blows, the antennas(cross-arms) mounted on tower are going to twist and sway. The condition system designer will permit only for a limited amount of twist and sway. Beyond this level of twist and sway, the communications will be lost, and power transmission result also affect, even power broken. Lesser twist and sway will require the tower to be more rigid, therefore tower will be more expensive.

        d) Any constraint on geometry of towers – Broad casting towers will require a specified length of tower to be of specified width only. A specified length of top portion is normally required to be parallel to mount the antennas with vertical space diversity. Space available on ground may be constrained due to nearby buildings or installations. This constraint will require the base of the tower to be less than the space available. Buyer may be interested only in 3 legged or in 4 legged tower. This should be specified to get desired offer. The top width of the tower, if required to be of a particular value, it should also be specified too.

        e) Soil Report - If foundation cost is to be clubbed with tower structure cost to establish a total minimum cost solution, then soil's safe bearing capacity and level of water table should be provided. A regular soil investigation report will be helpful.

      • Question 4. Which specifications for the power transmission line steel tower must be specified by tower buyer/ Communication system designer?

        Here is the climate condition data needed the buyer must provide for design:
        d) Max wind speed(m/s)
        e) Max ice thickness(mm)
        f) Lowest temperature(°)
        g) Highest temperature(°)
        n) Soil Report
        Here is the tower Design data needed by buyer for design:
        a) Tower type
        b) Conductor and ground wire type  
        c) Conductor Max operating stress(MPa)
        Ground wire Max operating stress(MPa)
        d) Number of circuit
        e) Angle(°)
        f) Horizontal span(m)
        h) Vertical span(m)
        i) Safety factor of conductor and ground wire
        j) Material
        k) sides (only for monopole tower)
        m) Taper
        n) Horizontal stress(KN)
        o) Down force(KN)
        p) Pole deflection(%)
        q) Tower bending standard value (KNm)
        r) Rough weight(kg)
        s) Anchor qty 
        t) Anchor diameter (mm)
        u) Nominal height 
        v) Outline drawings of tower

      • Question 5. Apart from structural parameters, which other necessary or optional parameters are required to be specified by the tower buyer/user?

        As tower is basically a structural support for antenna or cross arm for conductor or earth-wire with accessories, all necessary parameters required are structural parameters only
        For details of structural parameters required to be specified, see Answer of Q3  and Q4 above.
        Following could be further necessary/optional parameters for supply of tower materials
        a) Quantity of antenna interfaces required. Diameter & length of pipe should be specified.
        b) Length of horizontal cable ladder or gantry, with or without supports
        c) Quantity of Aviation obstruction Lights
        d) Length of electric cable, if required
        e) Quantity of Lightening Arrestor, if required
        f) Size & Length of down conductor for lightening arrestor required
        g) No of grounding pits required
        h) Size of ground electrodes
        i) Paint required
        j) Foundation Bolts
        k) Foundation templates
        l) Nameplate/signage required for tower

      • Question 6. How about your company Quality Policy?

        It is QINGDAO MEGATRO HOLDING INC.’s objective to become and remain the market leader with respect to the quality of its products and services. To achieve this objective, the QINGDAO MEGATRO HOLDING INC. shall:
        Deliver quality products and services that through their life fulfill and exceed the needs and expectations of our customers at a cost that represents value.
        Achieve quality by preventing problems rather than by detecting and correcting them after they occur.

        Strive for excellence through sustained effort towards continuous improvement in quality.
        Top management of QINGDAO MEGATRO HOLDING INC. is committed to the implementation and support of managerial and operational systems to realize this goal. Top management is committed to provide all resources needed to realize the products and services with the required quality level. Complete customers satisfaction is the ultimate goal of the QINGDAO MEGATRO HOLDING INC.

        The company management team had defined this quality policy in relevance to its objectives.
        This policy should be well understood at all levels of the company.
        Top management reviews that quality objectives and policy periodically.

      • Question 7. How about your tower Inspection?

        ISO Certification of the company authenticates our credibility and quality of the products as well as services offered. Tower designers are first generated by the expert engineers and then are sent for third party approval by China electric power design institute or by our clients. MEGATRO is very particular about the quality of the products and for retaining the superior level of quality; we entail new technological advancements and improvements in our working.

        The products that we offer comply with the specified international standards. As per the client’s specification, technical requirements and instructions, then end customer carry out the installation work without wasting any time. Our ultimate aim is always focused towards attainment of customer’s satisfaction. In a bid to gratify them up-to the hilt, we carry out galvanization of the tower so that left holes get coated and weld joints get protected.

        The fabrication and inspection of tower must follow relevant codes and documents as: Technical Requirement of the Tender Document
        General Specification for Tower Fabrication as per drawing 
        Relevant national codes and standards
        In house prototype inspection done by internal QA Team, Third party & by Customers also as applicable for the final approval and for Mass production
        For details please contact us to ask “Megatro Quality control documents”


        Quality Standards:
        ·GB/T2694-2003  for Fabrication of Towers
        ·DL+T+5130-2001   for tubular tower design
        ·GB/T1591-1994 and GB700-88   for raw material –steel
        ·GB/T13912-2002 for Zinc Coating
        ·GB3098.1-2000 for bolt, nut and washer
        ·ISO 9001 : 2000 for Quality Management Systems
        Also we check tower quality as per client country standard, such as IS, BS, JIS, EN, DIN, ASTM, and related standard. 

      • Question 8. How about your production ?

        Our machinery and workers are among the most sophisticated in the industry. They include:
        ·Fully automated CNC Angle cutting, punching and marking machines
        ·MIG Welding machines
        ·Motorized radial drilling machines
        ·Superior balancing machines
        ·In-house galvanizing units (7 Tank process of Galvanization) and more…
        ·CNC Plasma Profile cutting machines
        ·Bending machine with 3200 tons pressure
        ·Certified Welder with many years skills
        For more details please contact us to tower fabrication process and quality control procedures.

      • Question9. Which are the standards for tower?

        There are no standards for tower as a whole. But standards are available
        a) To estimate the wind load on tower structure, tower appurtenances, antennas, ladder, cable tray etc.
        b) To estimate the earthquake load on tower
        c) To estimate the Ice load on tower
        d) To estimate the dead load on a tower Standards are also available for working out permissible stress in any member of the tower.
        Working out the forces experienced by any member of the tower due to applied external loads is normally done by well established scientific methods.
        Elaborate software with capability of Finite Element Analysis (FEA) or dynamic analysis have been developed for doing these calculations. Also we use TMA software (Tower-Manufacturing Assistant) to set out workshop drawings.

      • Question 10 how about your products standard and code?

        We adopt the below productions for tower fabrication & inspection and delivery.

        No

        Code

        DESCRIPTION

        1

        GB/T2694-2003

        Transmission line tower - - Technical requirements for manufacturing

        2

        JGJ81-2002

        Technical specification for welding for steel structure of building

        3

        GB9787-88

        Measuring and allowable tolerance for hot-rolled equal angle

        4

        GB709-88

        Measuring and allowable tolerance for hot-rolled plate and strip

        5

        GB/T699-1999

        Quality Carbon Structural Steel

        6

        GB/T1591-1994

        Low alloy high strength structural Steel

        7

        GB700-88

        Carbon Structural Steel

        8

        GB222-84

        Method of sampling steel for determination of chemical composition and permissible variations

        9

        GB/T228-2002

        Method for Tensile testing of metals

        10

        GB/T232-1999

        Method for Bending test of metals

        11

        GB/T5117-1995

        Carbon Welding Rod

        12

        GB/T5118-1995

        Low Alloy Welding Rod

        13

        GB/T8110-1995

        Welding wires for gas shielding arc welding of carbon and low alloy steels

        14

        GB/T10045-2001

        Carbon steel flux cored electrodes for arc welding

        15

        JB/T7949-1999

        Weld outer dimensions for steel construction

        16

        GB50205-2001

        Test Standard for Acceptance of Steel Structure

        17

        GB/T470-1997

        Zinc Ingot

        18

        GB3098.1-2000

        Mechanical properties of fasteners-Part 1:Bolts, screws and studs

        19

        GB3098.2-2000

        Mechanical properties of fasteners-Part2: Nuts, and thread

        20

        GB3098.3-2000

        Mechanical properties of fasteners-Part3: Fastening screw

        21

        GB/T5780-2000

        Helical Bolts Grade C

        22

        GB/T41-2000

        Helical Nuts Grade C

        23

        GB/T90-2002

        Flat Washer Grade C

        24

        GB/T13912-2002

        Metal Coating, Technical Requirement and Test Method for Hot-dip galvanized Metal Parts

        American Standards:

        Standard

        Description

        ASTM A6/A6M

        Standard specification for general requirements for rolled structural steel bars, plates, and sheet piling.

        ASTM – 6    

        -  General Requirements for delivery of Rolled Steel Plates, Shapes, sheet Piling Bars for  structural used

        ASTM A36/A36-M-97a

        Standard specification for Carbon structural steel

        ASTM A123 / A123M-02

        Standard specification for Zinc (Hot-Dip Galvanized) Coatings on iron and steel products

        ASTM A143 / A143M-03

        Standard Practise for Safeguarding Against Embitterment of Hot-Dip Galvanized Structural Steel Products and Procedure for Detecting Embitterment

        ASTM A153/ A153M-05

        Standard specification for zinc coating (Hot-Dip) on iron and steel hardware

        ASTM A – 194  

        -   Grade for bolt

        ASTM A239

        Standard practice for locating the thinnest spot in a zinc (Galvanized) Coating on Iron or Steel Articles

        ASTM A242

        Standard specification for High-Strength Low-Alloy Structural steel

        ASTM A307

        Standard Specification for Carbon Steel Bolts and Studs, 60000 PSI Tensile strength

        ASTM A370-06

        Standard Test Methods and Definitions for Mechanical Testing of Steel Products

        ASTM A325

        Standard Specification for structural bolts, steel, Heat treated 120/105 ksi minimum tensile strength

        ASTM A-325 or A-354  

        -  Galvanized hexagonal head of  connection bolt

        ASTM A325-97

        Standard Specification for High-strength Bolts for structural steel Joints

        ASTM A384 / A384M-02

        Standard Practise for Safeguarding Against Warpage and Distortion During Hot-Dip Galvanizing of Steel Assemblies.

        ASTM A394-93

        Standard Specification for steeltransmission Tower, Bolts, Zinc Coated and Bare

          ASTMA – 563

        -    Class and size of nuts

        ASTMA – 572   

        - Chemical composition of steel

        ASTM A572/A572-97c

        Standard specification for High-Strength Low-Alloy Columbium-Vanadium Structural steel

            ASTMA – 615  

        -   The anchor bolt material

        ASTM A673 / A673M-07

        Standard Specification for Sampling Procedure for Impact  Testing of Structural Steel

        ASTM B201

        Standard practice for testing Chromatic coating on Zinc and Cadmium surfaces

        ASTM  E94-93

        Standard Guide for Radiographic Testing

        ASTM E 709-95

        Standard Guide for Magnetic Particle Examination

        ASCE Manual 72    

        -  Load testing a simple structure

        ASCE 10-97

        Standard Design of latticed steeltransmission structures

        AWS D1.1

        American Welding Society D1,1/D1,1M structural Welding code- Steel

        ANSWERI B-182-2

        Bolts, nuts and washers dimensions


        DIN VDE 0101                                     -  Isokeraunic Level
        VDE 0201                      - Climatic and environmental   conditions
        CVDE 0210 -  Minimum safety factors under    simultaneous working loads
        ISO R898 Mechanical Properties of Fasteners
        BS EN ISO 1461:1991 - High dip galvanized coatings on fabricated iron and steel articles. Specifications and standards
        A) BS 5950: Welding Terms And Symbols
        B) BS 729: Hot - Dip Galvanised Coating On Iron And Steel Articles
        C) BS 2901: Filler Rods And Wires For Gas Shielded Arc Welding: Part 1 Ferritic Steels
        D) BS 3692: ISO Metric Precision Hexagon Bolts, Screws And Nuts
        E) BS 4360: Weldable Structural Steel
        F ) BS 5135: Metal - Arc Welding Of Carbon And Carbon Manganese Steel
        G) BS 5950: Part 1: Code Of Practice For Loading Latticed Tower & Masts
        Part 2: Guide To The Background And Use Of Part 1"Code OF Practice For Loading"
        Part 3: Strength Assessment of Members
        H) DD 133 (1986): Code Of Practice For Loading Latticed Tower & Masts
        I) BS 4592 (1987): Part 2: Specification For Expanded Metal Grating Panels
        J) BS 4592 (1977): Code Of Practice For Protective Coating Of Iron And Steel Structure Against Corrosion
        K) BS 4190: Bracing & Flanged Bolts
        L) BS 4190: Rolled Steel sections, Flats & Plates


      86-532-55588298

      卡通 自拍 亚洲 另类

      <tbody id="bbqa4"><noscript id="bbqa4"></noscript></tbody>
    3. <rp id="bbqa4"><samp id="bbqa4"></samp></rp>
      <th id="bbqa4"></th>
      1. <em id="bbqa4"></em>

      2. <button id="bbqa4"><acronym id="bbqa4"></acronym></button>