Do you have Water Tank Crack Issue ?

Over the years of usage, 3 major issues that cause the Water Tank to crack:

1. Water Tank Recommendation– Under manufacturer’s recommendation, it will be ideally to design using float-valve than pilot valve as the incoming water refill through the pilot valve creates impact on the water tank, as the direct high-pressure drop to the bottom panel creates moment on the entire water tank. Pilot Valve design does create more pressure as compare to Ball Float-Valve solution.
2. Mechanism Faulty – The faulty equipment (example: Float-valve or motorized valve, etc) will result in the continuous of water refilling (even though the excess water will flow out thru the over-flow pipe), causing the tank will to be pressurized, resulting the deformation of the water tank panels
3. Maintenance Operation
   • Tie-Rod Deformation – This is due to the maintenance operation carried out by maintenance personnel that used the tie-rod as a supporting structure when carrying out the cleaning work.
   • Compartment Tanks Cleaning – When carrying out maintenance work for partition tanks, (Tank A & Tank B) under manufacturer’s recommendation, it must reduce the effective water capacity in the Compartment Tank A2 to 50% or less, as water movement IN and OUT of the compartment tank A2 will create slow effect on the water tank pressurization
   • Wire (Insect) Mesh – Over the years, the wire mesh at the end of the discharged pipe will be partially “choked” which eventually reduce the water flow. This is also part of the reason that causes the pressure to built-up by incoming water thru booster pump. This event happened during the overflow process.
   • Refilling Process during Maintenance – In a typical situation after the cleaning work, technical personnel will turn-on the refilling process at 100% for fast refilling process. The maximum refilling process will create a big impact & moment to the water tank panel.

Preventive Measurement of Water Management System

Water Tank pressurization and water moments are great impact to the panels, extra precaution is needed to ensure the reliability of the equipment. The following are some of the recommendation:

Pump Design Recommendation – For All Booster Pumps design, the desired pressure head recommended to be around 3m to 5m head, to the water tank. Based on initial design calculation additional 15% to 20% buffer will be practized. When the requirement reaches to the pump supplier, thus increase another 5% to 10% more, all these exercise eventually will create more pressure, turbulence and wave inside the water tank during the top up period.

Control Measurement – In some instances, the booster pumps are design for a few number of water tanks, and the actual calculation is based on the total number of water tank demand in order to size the booster pump. During the operation, one of the compartment tank alert for low level signal, therefore the booster pump will activate serving all the water flow to this particular compartment unit with full-throttle (100% load) thus create pressurization to this compartment.

Operation Team Handover after DLP – During Testing & Commissioning stage, because of the pump oversizing, certain valve opening may have adjusted accordingly to suit the operation of the desire testing criteria. After the end-of-DLP, different maintenance team be taking over the system, it is important that the fine tuning on pump or valve need to be documented and hand over accordingly, otherwise it will cause some extra pressure to the existing tank again

If the pump is damage and replacement work is carry-out by another team, never practise over-size further, as it will further damage to the water tank operation that causes higher water movement, creating leaks, crack and etc