Sunday, January 31, 2010

Lamellar tearing - useful information for candidates attending NDT Training


*In general occurs beneath the T-joint welds
*can be observed in thick plates with poor through-thickness ductility
*Usually occurs in large welds
*Welding heats the steel and it expands and while cooling “Tears” the steel

To experience Quality NDT training courses in NDT e-mail us your training requirements to: training@trinityndt.com, visit and enroll at www.trinityndt.com or call 'Course Director' at +91 99009 29439

Thursday, January 28, 2010

MPT by Trinity NDT- Inspection company in Bangalore, India




Magnetic particle testing-MPT by Fluorescent examination reveals severe grinding cracks throughout outer surface and inner surface of the tested sleeve components. It is suspected that the cracks are due to improper heat treatment and/or grinding operation/s. All the cracks are of network in nature and cannot be repaired to use the components further. Magnetic particle testing carried out with high sensitive magnetic particles with high intensity black light and latest NDT equipments. Entire lot rejected due to the defects.

To carry out the NDT tests, Trinity NDT is equipped with latest state of art NDT equipment to identify very fine cracks by using latest NDT technologies, equipments and qualified personnel with in-house NDT Training facilities to conduct the tests according to national/ international standards, Codes and client's specific requirements.

Magnetic Particle and Liquid/dye Penetrant Testing Capabilities at Trinity NDT:

* Magnetic particle testing and liquid/dye penetrant testing of raw materials,
components, and welds

* Magnetic particle testing -MPT can be performed to ASTM E709,ASTM A275, or other
client specified requirements

* Liquid/dye penetrant testing can be performed to ASTM E165 or other customer
specified requirements

* Testing performed by SNT-TC-1A qualified personnel with extensive experience
Portable testing equipment for onsite testing

* NDT Test Reports

* Custom NDT procedure development capability


Weld Inspection Capabilities:

* Certified NDT & Welding Inspectors

* Magnetic Particle and Liquid Penetrant Weld Testing

* Specialize in AWS D1.1 weld inspections

* Onsite inspection availability

* Weld Inspection Reports can be provided


To experience professional Nondestructive testing inspection services and training courses in India to level 1 level II e-mail us your testing and training requirements to: training@trinityndt.com, To know more about us please visit and enroll at www.trinityndt.com or call 'Course Director' at +91 99009 29439.

Wednesday, January 20, 2010

Stainless steels, Cast Iron- useful information for candidates attending NDT Training




Stainless Steels

Stainless steels are at least 12 percent chromium and many have high nickel contents. The three basic types of stainless are:

1. Austenitic
2. Ferritic
3. Martensitic

Martensitic stainless steels make up the cutlery grades. They have the least amount of chromium, offer high hardenability, and require both pre- and postheating when welding to prevent cracking in the heat-affected zone (HAZ).

Ferritic stainless steels have 12 to 27 percent chromium with small amounts of austenite-forming alloys.

Austenitic stainless steels offer excellent weldability, but austenite isn’t stable at room temperature. Consequently, specific alloys must be added to stabilize austenite. The most important austenite stabilizer is nickel, and others include carbon, manganese, and nitrogen.

Special properties, including corrosion resistance, oxidation resistance, and strength at high temperatures, can be incorporated into austenitic stainless steels by adding certain alloys like chromium, nickel, molybdenum, nitrogen, titanium, and columbium. And while carbon can add strength at high temperatures, it can also reduce corrosion resistance by forming a compound with chromium. It’s important to note that austenitic alloys can’t be hardened by heat treatment. That means they don’t harden in the welding HAZ.

Cast Iron

The carbon content of cast iron is 2.1 percent or more. There are four basic types of cast iron:

1. Gray cast iron, which is relatively soft. It’s easily machined and welded, and you’ll find it used for engine cylinder blocks, pipe, and machine tool structures.

2. White cast iron, which is hard, brittle, and not weldable. It has a compressive strength of more than 200,000 pounds per square inch (PSI), and when it’s annealed, it becomes malleable cast iron.

3. Malleable cast iron, which is annealed white cast iron. It can be welded, machined, is ductile, and offers good strength and shock resistance.

4. Ductile cast iron, which is sometimes called nodular or spheroidal graphite cast iron. It gets this name because its carbon is in the shape of small spheres, not flakes. This makes it both ductile and malleable. It’s also weldable.

Tuesday, January 19, 2010

Trinity NDT Level II (2) Courses at NDT Training center, Bangalore, India


Trinity institute of NDT technology, India announces training course schedule from 19th February 2010 at NDT Training center in Bangalore.

'Trinity NDT' SNT-TC-1A courses are comprehensive in nature. The goal of these courses is to provide a complete training program covering all the topics covered by SNT-TC-1A for the test method and prepare the student for certification as a Level I or Level II Inspector.

We try to explain each subject in practical terms and explain how it applies to actual testing applications

Hands-on time is stressed to give each student the opportunity to apply each lesson on test pieces and actual flawed specimens

Upon completion of the course, each student is given general, specific and practical tests as proof that he is prepared for certification. A course completion certificate is issued as well as detailing the results of the tests and final marks.

Salient features of our NDT Courses:

• Each Course Fee includes classroom study materials.

• All classes include metals processes and manufacturing, basic theory, industrial practices, applications,applicable safety standards, documentation, applicable standards and specifications.

• Special training sessions to explain metallurgical aspects, back ground of defects formation in different product forms by professional metallurgists and materials engineers.

• All courses include a combination of presentation and extensive hands on applications with different samples in order to reinforce learning and comprehension.

• Course instructors are ASNT Level III’s in the applicable method with minimum experience of 15 years each.

• Training and certification in wide range of NDT methods including
a. Ultrasonic Testing Level 1&2
b. Magnetic particle testing Level 1&2
c. Liquid/Dye penetrant testing Level I/II
d. Radiographic testing Level 1&2
e. Radiographic interpretation Level 1&2
f. Visual testing Level 1&2

• All courses meet or exceed industry standards like ASNT SNT‐TC‐1A

• Training programs as per specific requirements at client's locations all over India and abroad.

To experience professional training in NDT e-mail us your training requirements to: training@trinityndt.com, visit and enroll at www.trinityndt.com or call 'Course Director' at +91 99009 29439.

Monday, January 18, 2010

How Hydrogen Cracks Occur? Useful information for NDT Technicians


Whenever hydrogen cracks are generated, three things occur (are present) simultaneously:

1. Dissolved Hydrogen
2. Tensile Stresses
3. Low Ductility

This is the sequence of events leading to this deadly cracking.

a) Hydrogen enters the arc either by the shielding gas, flux or material contamination and dissolves into the weld metal itself.

b) As the weld cools, it becomes saturated in hydrogen, all of which diffuses out into the HAZ.

c) If cooled quickly (rapid), the hydrogen is retained in the 'austenite' instead of escaping.

d) The Hydrogen is trapped and seeks rifts and discontinuities in the material lattice and concentrates at these points.

e) The external stresses generated due to transformation act with the hydrogen to enlarge the 'discontinuities' to 'crack' size. This hydrogen may contribute to cracking by lowering the strength of the lattice and/or by adding to the stresses at the discontinuity level.

f) Crack growth takes the crack-root away for the hydrogen concentration and may be interrupted until the hydrogen diffuses to a new root location. This leads to the time-dependent behavior of the cracking phenomenon.
The Main Defence:

Preheat - The main reason for this heat is to assist in removing hydrogen from the weld by allowing the weld to cool slower; (diffusing hydrogen out) and remaining more ductile, thus resisting cracking.

Thursday, January 14, 2010

Greetings for happy Sankranti Festival



Makar Sankranti is one of the most auspicious day for the Hindus, and is celebrated in almost all parts of the country in myriad cultural forms, with great devotion, fervor & gaiety. The festival of Makar Sankrant traditionally coincides with the beginning of the Sun's northward journey (the Uttarayan) when it enters the sign of Makar (the Capricorn). It falls on the 14th of January every year according to the Solar Calendar. Lakhs of people take a dip in places like Ganga Sagar & Prayag and pray to Lord Sun.

Makar Sankranti holds special significance as on this day the solar calendar measures the day and night to be of equal durations on this day. From this day onwards, the days become longer and warmer. It is the day when people of northern hemisphere, the northward path of the sun marks the period when the sun is getting closer to them. The importance of the day was signified by the Aryans who started celebrating this day as an auspicious day for festivities. The reason behind this may be the fact that it marked the onset of harvest season. Even in the epic of Mahabharata, an episode mentions how people in that era also considered the day as auspicious. Bhishma Pitamah even after being wounded in the Mahabharata war lingered on till Uttarayan set in, so that he can attain heavenly abode in auspiciuous times. It is said that death on this day to brings Moksha or salvation to the deceased.

Wednesday, January 13, 2010

New ultrasonic testing flaw detector for Trinity NDT equipments at Bangalore, India


To provide latest technology and better flaw analysis services for the esteemed customers 'Trinity NDT' Bangalore, India has added new Ultrasonic Flaw detector 'Eintein II DGS' to its equipments. The equipment has latest features.

The Ultrasonic flaw detector (equipment) has special and latest technologies available in India for ultrasonic testing as follows:

* Built-in DGS/AVG curves for time proven flaw size evaluation

* It has TCG (Time Controlled Gain) which compensates for amplitude decay with
distance. A very useful feature.

* Dynamic DAC curves which allow change of Test Range and Gain after plotting them

Tuesday, January 12, 2010

Nondestructive testing-NDT courses at Bangalore, India


A premier NDT Institute conducting courses on Non-destructive testing-NDT level 1, Level 2 in different methods which includes RT, UT, MT, PT, VT.

Courses are scheduled to start from 16th & 25th of January 2010.

Interested candidates can log on to www.trinityndt.com and enroll for the NDT courses.