Winter Hydro Test - Risk vs Reward
Understanding API 650 and Proper preparation during a Winter Hydro Testing
As a second part to "It's Not Just Filling a Tank with Water," understanding the risks of hydro testing API storage tanks during freezing weather (weeks or days) and proper planning, equipment, contingency, test procedures and skilled/trained personnel is key to success. Tank codes don't include designs for storing "ice," nor can you predict that powerful frozen steel components will negatively react if freezing occurs.
A reality of the industry is that API tanks may require, at times, to be tested during cold and freezing temperatures. These tests may be done to get a tank asset back into service in preparation for seasonal cargo deliveries or simply to get valuable commodities back into the supply chain. Whatever the reason, it is fact that tanks are tested in winter, and while these tests may be planned when weather is warmer and more predictable, winter is less predictable and weather changes drastically day to night in some regions. The risks are much greater.
With some tests taking multiple days or having multiple transfers and always running 24/7, test water temperature maintenance is most important and needs to be considered. In some cases, the owner specification may dictate test water temperature greater than that outlined in API codes, but having sufficient temperature in the test water to provide time to react to daily swings in temperature provides comfort.
When considering winter hydro testing, the engineering and designer team at NCS Fluid Handling Systems design for heating systems with specialized heaters designed to work as an intricate part of the tank heating and circulating system. As specialists in the winter hydro testing field, NCS Fluid Handling Systems' skilled technicians work year-round training on the use of and improving the performance design of these specialized heating and circulating systems, taking a "lesson learned" approach to consider improvements to the overall system efficiency.
As industry specialists, our NCS designers and project managers can provide valuable insight into the system design considering special situations not widely known, such as adequate heat and circulation protection for areas including manway and nozzle necks. As there is virtually no water heat transfer into these areas, they are subject to freezing during testing if system designs do not consider the special conditions that lie within these areas of the tanks. Freezing of a nozzle neck or manway could lead to catastrophic failure during testing. Simply, tanks and their appurtenances are not designed to store ice.
When evaluating or preparing for a winter season hydro test, consider consulting with NCS Fluid Handling Systems engineering designer(s) to consider the various options given your unique conditions and variables. The risk of using a low-cost provider without knowledge or sufficient background may not outweigh the reward, as a costlier outcome with significant delays may be the result.
Contact Clint at 780-903-6206 or Caillan at 780-886-9454 to schedule a visit or a call to consult on your best options, or read more about tank hydro testing.