Woow....Blogger punya Fitur Baru

  


Hahaha.....
   
   Setelah sekian lama (1 tahun lebih sepertinya) tidak nulis di Blog, ternyata Blogger.com mengalami banyak sekali perubahan. Salah satunya (dari salah banyak, tentunya) adalah adanya fitur Statistik yang tentu saja sangat bermanfaat.

   Ada lagi fitur untuk mengetahui berapa banyak pemirsa yang baik hati yang mengakses blog saya selama dalam kurun waktu tertentu. Tergantung frekuensi pencatatan dari blogger.com sepertinya.

   Overall,
   Sepertinya saya akan mulai lagi Go-Blogging. hehehe.... Terlebih ada aplikasi untuk smartphone yang memungkinkan kita untuk update Blog dari mana saja.

Cihuuuy !!!

Aktif Nge-Blog Lagi ?

             Sumber : http://blog.hubspot.com

Masya Allah,

   Ternyata sudah satu tahun lebih blog kesayangan-ku ini terlantar. Padahal tiap minggu saya selalu mendapat kiriman "Blog Activity Report" dari Blogger.com yang dikirimkan ke email.
   Lucunya, di manapun saya berada akun email itu selalu menemani hari-hari saya. Sampai waktunya cuti sekalipun.

   Kenapa kok sampai tidak terurus ?
   Hmm....pasti ini karena efek "Slow Internet Connection" di rumah selama satu tahun kemarin. Maklum, di tahun 2010 - 2011 kemarin saya lebih banyak mengandalkan akses internet dari kantor yang memang kencang. TAPI tidak punya akses untuk Go-Blog, bahkan sekedar update status. Hahaha.....Mo eksis tapi gak modal. Akhirnya yaa...Blog being Abandoned Temporarily.

            Sumber : http://www.gabrielweinberg.com

   Trus, kenapa kok sekarang mulai aktif Go-Blog lagi. Benarkah ??
   Hmmm....jangan terburu-buru menyebutkan "Aktif", who knows dear !

   Yayaya, apapun alasan saya mengenai aktif / tidaknya nge-blog lagi hanya saya yang mengetahuinya. Yang pasti, sementara waktu mengisi kesendirian di rumah pasca pulang kerja, Karena anak-anak & Istri saya saat ini berada di lain tempat, insya allah saya akan mulai lagi mengisi kekosongan Blog ini.

GANBATTE KUDASAI !! 

Test Services in O&G Sector

Mechanical Testing

Mechanical testing or engineering test is performed to determine various mechanical properties of materials such as strength, hardness, ductility, toughness, brittleness, etc. There are several types of test to determine various mechanical and physical properties of material. The precision results of these tests is utilised to determine suitability of materials for the field application.


A. Tensile Testing

Tensile test is the most elementary type of mechanical test performed on materials. Tensile tests are simple, economical and traceable to the national standards. A tensile test also known as tension test is performed by holding the test items or test specimens in a suitable equipment. An axial pulling force is applied on the test item or test specimen and its behaviour under force is recorded on a conventional graph or chart or computerised data acquisition method.

Generally this test is performed at ambient temperature. Where a material is subjected to elevated temperature such as boilers and pressure vessel applications, a high temperature tensile test is performed. In Australia, AS 2291 specifies test method requirements for high temperature tensile test.

This test provides information such as Proof load, 0.2% proof stress, Yield strength, Ultimate tensile strength or breaking force, Elongation, Reduction of area, modulus of elasticity, etc. 

A.1. Longitudinal Tensile Test

As the name suggest, longitudinal tensile test is performed on the test specimen, which is extracted in the longitudinal direction of the sample of item such as plate or pipe. Longitudinal tensile test is the most common tensile test performed on all types of materials.
AS 1391, AS 2205.2 and ASTM E8 are the most common standards used to perform this test. 

A.2. Transverse Tensile Test

Transverse tensile test is performed on the test specimen, which is extracted in the transverse direction or across the sample of item such as plate or pipe. This test is performed to measure transverse tensile strength, yield strength, proof stress, elongation and reduction of area. The transverse tensile strength is very important mechanical property in pipes and Hoop’s stress calculation.

Transverse tensile test is performed on pipe materials, welded joints and occasionally on pressure vessel plates where design requirements demand. AS 1855, AS 2205.2 and EN 895 are some of the common standards used to perform this test. 

A.3. ‘Z’ Direction Tensile Test

Through thickness tensile test or ‘Z’ direction tensile test is performed to evaluate mechanical properties mostly in steel. The test involves applying tensile forces on a test specimen whose axis is perpendicular to the rolled surfaces of steel plate. The primary purpose of the test is to measure resistance to lamellar tearing by determining reduction of area and ultimate tensile strength in ‘Z’ direction.

EN 10164, ASTM A770, AS 3678, AS 1391 are some of the common standards used to perform test.

or refer to other article in this blog

A.4. Weld Tensile testing

Tensile test is performed on welded test specimen as part of the weld procedure (WPS / WPQR) qualification, welder qualification, weld performance qualification and Production weld qualification. Generally, a transverse tensile test is performed where the weld metal is oriented transverse in the centre of the specimen. A longitudinal tensile test is performed when the weld metal qualification is required or WPS qualification demands.

AS 2205.2, EN 895 and ASME IX QW 150 are some of the common standards applied to perform weld tensile test. 

A.5. Tension test

Tension test is similar as tensile test. The terminology ‘tension test’ is used when the sole purpose of the test is to determine ultimate breaking force or failure load. Tension test is also commonly used to perform proof load test. Occasionally, yield force or deformation force is recorded during tension test. 

A.6. Bond Tension Test

The use of adhesives in engineering applications in progressively increasing. These adhesives are used to bond various metallic panels, protective coatings, wear resistance coatings, etc. The bonding or adhesion on the subsurface is very crucial in engineering application and severe corrosive environment. A coating bond test or adhesive test is performed to measure tensile force required to break or peel off the coating (quantitative test). 

A.7 Proof Load Test

A proof load test is performed on various components to ensure that these components can withstand the design load without failure or without yielding (unacceptable deformation). The test is performed by applying force in the range of 1.1 to 1.5 times of the design load or maximum allowable working load (MAWL) for a specified duration.

TO BE CONTINUED . . . .

Z-Grade Quality Material (Through Thickness Property)

    Dalam suatu proses pengelasan, akan menghasilkan tegangan (stress) pada pelat induk. Dimana tegangan tersebut dapat menyebabkan timbulnya cacat retak. Retak/ pembukaan material yang mempunyai arah paralel terhadap permukaan logam disebut sebagai lamellar tearing, cacat ini akan menyebabkan kerusakan material pada posisi tegak lurus ketebalan pelat.


    Lamellar tearing, secara kamus arti kata “lamellar” adalah lapisan tipis, membran atau jaringan berbentuk pelat. Sedangkan “tear” adalah tertarik sobek manjadi beberapa bagian. Sehingga lamellar tearing pada material dapat diartikan sebagai keretakan material akibat pengelasan yang berbetuk lapisan yang terletak di dalam material dan searah permukaan material pelat tersebut. Lamellar tearing ini pada umumnya terjadi pada material pelat baja rolled, dimana ini adalah kondisi berbahaya yang terjadi ketika material pelat yang mempunyai sifat kelenturan yang rendah (low ductility) yang dilas secara tegak lurus terhadap arah ketebalan pelat tersebut.

     Keretakan ini dapat terjadi dimana:
- Regangan (strain) karena kontraksi akibat perubahan suhu terjadi pada arah ketebalan pelat (through thickness direction of plates)
- Atau adanya inklusi/sisipan material non-metal yang berupa bidang lapisan tipis dimana bentuk utama dari sisipan (planar) tersebut searah dengan permukaan pipa. Sehingga regangan (strain) akibat kontraksi tersebut akan memaksa inklusi non-metal tadi sebagai pemicu untuk membentuk bukaan planar pada arah pararel terhadap permukaan pelat.

    Pada struktur baja yang dilas, dimana pada posisi beban ditanggung tegak lurus terhadap permukaan pelat, lamellar tearing dapat menjadi penyebab awal kerusakan struktur yang lebih besar.
Pada level kualitas pelat baja normal, biasanya pengujian telah dilakukan searah rollingnya (memanjang pelat – sumbu x) maupun tegak lurus arah rollingnya (melebar pelat – sumbu y), dan property material pada arah tegak lurus ketebalan pelat (sumbu z) tidak disebutkan.

    Dengan teknologi produksi yang khusus pada saat ini serta pengurangan kandungan belerang, kebanyakan pabrikan baja telah mempunyai kemampuan untuk memproduksi pelat baja dengan property untuk arah ketebalan pelat (sumbu z) tersebut, dimana pelat dengan jenis ini disebut sebagai material dengan kualitas Z-grade. Material Z-grade Quality ini meminimalisir resiko terjadinya lamellar tearing, karena material ini mempunyai ketahanan (ductility) yang lebih pada arah tebalnya dibandingkan dengan material kualitas normal grade.


    Untuk mengetahui sejauh mana ketangguhan sifat-sifat (property) material Z grade quality ini, dilakukan pengujian tarik yang spesifik (searah sumbu Z) pada sample material, dimana jika menghasilkan reduction area yang tinggi maka material ini dapat dikategorikan mempunyai Z grade quality yang baik.

    Tentu saja prosedur pengujian dan berapa besar nilai minimal reduction area yang harus didapat supaya material tersebut dapat dikategorikan baik/ tidak, harus mengacu pada standard industri yang berlaku.
Beberapa standard industri a.l: ASTM D7291, EN 10164 atau Rule badan klasifikasi seperti GL, BV, LR, ABS atau DNV juga menyediakan prosedur pengujian serta criteria keberterimaan untuk material dengan kategori Z-grade quality ini.


    Sekilas jika meninjau GL Rule for Material & Welding - Section1: Steel Plates, Strips and Bars, dimana disitu untuk category Z-grade material ditentukan berdasar reduction area yang dihasilkan pada saat pengujian tarik sample dengan orientasi searah tebal material (seperti gambar diatas). Ada 2 kategori Z-grade material menurut GL rule, yaitu Z25 dan Z35, dimana Z25 adalah jika reduction area yang dihasilkan sebesar 25% minimum, sedang untuk Z35 reduction area yang dihasilkan minimum harus sebesar 35%.

    Pengujian dilakukan pada 3 specimen uji tarik (Z direction), dimana salah satunya boleh kurang dari 25% tetapi masih harus lebih besar dari 20% untuk Z25. Sedang untuk Z35 salah satu specimen boleh kurang dari 35% tapi masih harus lebih besar dari 25%.


    Pemakaian material ini umum diterapkan pada struktur bangunan lepas pantai, kapal ataupun floating unit sperti FPSO, FSO dan FSRU, yang biasanya dipakai pada bagian struktur yang mengalami beban vertical terhadap ketebalan pelat/material, seperti doubler plate pada koneksi antara deck plate dengan stool topside production module. 

sumber : Blog A.Z Ridwan

Intergraph® PV Elite™ : Vessel and Exchanger Analysis - Introduction

PV Elite™ is a comprehensive program for the complete structural design or analysis of tall towers, horizontal vessels and shell and tube heat exchangers according to latest standards from ASME, PD 5500 (British Code), UBC, EN 13445, API-579 and the Welding Research Council. 
PV Elite™ also offer a complete solution for vessel and heat exchanger design, analysis and evaluation. Users of PV Elite have designed equipment for the most extreme uses and have
done so quickly, accurately and profitability.

PV Elite™ evaluates the entire vessel, analyzing the effects of weight and bending due to wind and seismic loads. It combines these overall loads with pressure to design and/or check vessel wall thickness. Basing stress calculations on this total structural load ensures sufficient wall thickness for the vessel in its operating environment and ensures proper design of the vessel supports.

Element types include cylindrical shells; elliptical, spherical, torispherical, conical and flat heads; conical sections (including knuckles); body flanges; and skirts with base ring details. The program provides base ring, saddle, leg and lug design and also includes modules for analyzing vessel components such as nozzles, flanges, base ring and other vessel components.

 

 













To make the design process easy, the status bar constantly displays the position of the current element, its required thickness, its maximum allowable working pressure and its maximum allowable pressure in the new and cold condition. It can be used for both new design or re-rating. Graphic presentation keeps your data organized and confirms the integrity of the model. 

Data Collection
PV Elite makes defining pressure boundary conditions for vessels and exchangers easy, even for load sets that require significant data input. PV Elite streamlines data entry by breaking the input down into sensible subsets. Help on any input item is only a keystroke away.

Graphics
PV Elite’s graphical representation of analysis models helps ensure confidence in the input and results.With PV Elite, analysis models can be viewed and manipulated with complete ease.

Analysis Options
PV Elite performs calculations in accordance with ASME Section VIII Divisions 1 & 2, PD 5500 and EN 13445. Rules from API 579 (Fitness for Service) are also included for evaluating the current state and remaining life of existing vessels.

Output and Reports
To simplify inspection requirements, PV Elite lists the most important equations such as required thickness and maximum allowable working pressure (MAWP) and also groups results by type (e.g. internal pressure, external pressure, bending stress, nozzles and flanges). Overall results are summarized where the element or detail controlling the overall vessel MAWP is identified.

Materials and Codes
PV Elite is a global package with international code rules plus extensive region-specific content. Vessel material definitions, piping and steel component data, local wind loads and local seismic loads of many regional markets are all included.

Interfaces
PV Elite interfaces with other popular software packages for finite element analysis, foundation design and drafting. PV Elite also shares a bi-directional link to COADE CADWorx® Equipment module and COADE PV Fabricator™. 

Application Areas
Process and Plant Design, Piping, Equipment, Petrochemical, Chemical, Power, Offshore, Food, Beverage, Brewing, Pharmaceutical,Water Treatment and Shipbuilding.

Features Include:
• Vessel Design and Analysis
• Exchanger Design and Analysis
• Tubesheet Design and Analysis
• Rectangular and Non-Circular Vessel Analysis
• Individual Component Analysis
• Cutting-edge Graphics
• Design Tools and Wizards
• Comprehensive Error Checking
• Saddle, Leg and Skirt Design
• Analysis for Horizontal Shipping of Vertical Vessels
• User-definable Reports
• Wind Analysis
• Seismic Analysis
• International Vessel Codes
• Extensive Material Databases
• Steel Databases and Modeling
• Links to COADE CADWorx Equipment
• Links to COADE PV Fabricator


SUMBER : COADE and PVElite Brochure