Laboratory ISO 9001 vs ISO 17025

ISO 9001 or ISO 17025: How to choose a calibration company. ISO 17025 or ISO 9001: Which one is better? As a calibration company, we are sometimes asked which is better ISO 9001 or ISO 17025 certification. That really is the wrong question.  Both of these International standards are excellent.  The reason we said it is the wrong question is that they each have a particular focus. What is the difference between ISO 9001 and ISO 17025? ISO 9001 is a standard designed for the manufacturing and service sector and focuses the Quality Management System towards those major groupings. ISO … Continue reading Laboratory ISO 9001 vs ISO 17025

Fatigue on Weld

Designing for fatigue is very different than designing for static loads.  One of the biggest challenges is being able to estimate the loads, timing of the loads and duration of the loads.   If you look at a bridge you have to estimate the number of vehicles going on the bridge every day, the weight of these vehicles, and other forces and loads acting on the bridge such as its own weight (steel and concrete), wind loading, and pre-existing stresses such as those caused by welding. Girders are subjected to fluctuating loads which combined with temperature and fabrication quality will determine … Continue reading Fatigue on Weld

Damage stability calculations (Sample)

Damage stability calculations Calculations of the stability of damaged ship are complicated and tedious. At present, two different analysis concepts are applied: the deterministic concept and the probabilistic concept. For both concepts, the damage stability calculation shall be made according to the method of lost buoyancy. Unfortunately, the collision resistance is not considered when assessing damage stability and vessels with strengthened side structures are treated in the same way as single-hulled ships. The damage stability legislation is contained in the following Conventions or related mandatory Codes. – Deterministic concept – This method is based on damage assumptions such as damage length, transverse … Continue reading Damage stability calculations (Sample)


Damage Control Information (DCI) The Damage Control Information is a part of onboard documentation. The documentation should be clear and easy to understand. It should not include more information than this directly relevant to damage control and should be provided in the working language of the ship.   Visit: Shipbuilding Knowledge A-Z for more free topics on shipbuilding The DCI is intended to provide the ship’s officers with clear information on the ship’s watertight subdivision and equipment related to maintaining the integrity of the watertight boundaries so that in the event of ship damage-causing flooding proper precautions can be taken to … Continue reading SHIP DAMAGE CONTROL PLAN

Demagnetize prior to weld

Knowledge for Reference: Demagnetization: Magnetic field strength above a critical intensity is affecting the weld-ability. Well-known interference are: – Arc welding procedures are sensible to high magnetic field strengths. Welding in presence of magnetic fields may cause magnetic arc blow. Arc blowing is strongly reduced below field strengths of 16 A/cm (=20 Gauss). – In arc welding with filler wires (FCAW/GMAW/SMAW) , sticking of the wire to a side is caused when significant magnetic fields are present. The sticking is minimized below field strengths of 8 A/cm (=10 Gauss). – In electron beam welding (EBW), the quality of the welding is strongly affected by magnetism. At field strengths well below 2 A/cm (=2.5 Gauss) the disturbing influence on welding … Continue reading Demagnetize prior to weld

Questions and Answers for Marine Engineers

Explain the term water hammer indicating possible effects on the system ? Water hammer occurs when steam is admitted into a cold pipeline. The steam condenses producing both water, and a vacuum (when the water seals the pipeline from the steam supply). This vacuum causes the water plug to be drawn into the closed end of the pipe with increasing velocity producing high impact forces on the pipework. This impact force can be high enough to rupture the pipeline. State how the risk of water hammer may be avoided ? Water hammer is avoided by slowly admitting the steam into the cold line, and draining/venting … Continue reading Questions and Answers for Marine Engineers