Handling & Installation Technical Information

Tank construction design

The most important feature of a fiberglass tank is the corrosion resistance of the tank. Our corrosion barrier laminate is made up of the Inner Surface and Interior Layer combined. Our FRP tank is built using a mold to ensure a resin rich smooth internal barrier to create better corrosion resistance.

Tank Built Standards
  • Our tanks are constructed in accordance to BS, ASTM and ASME specifications
  • All tanks are tested for the degree of surface cure using Barcol hardness and Acetone test methods and visually inspected for laminate quality and built workmanship.
  • After installation of the tank, a hydrostatic test shall be performed.
  • Hold down lugs are provided on all vertical flat bottom tanks.
  • Support rings with legs of lugs are provided on all vertical dish bottom tanks.
  • Lifting lugs are provided for all large tanks.
  • All flanged nozzles are of hand lay-up construction with the pipe stub molded integrally with the pipe flange.
  • All closed top tanks are provided with a minimum 24 inch manhole and all tanks with a straight shell height greater than 12 feet shall have flanged side manhole of minimum 24 inches.
  • Threaded fittings shall be installed with laminates inside and outside as required per ASTM specifications and shall be of glass fiber reinforced resin with molded threads.
  • In the manufacturing process, the resins coat may stick to the steel lugs and since this interface between steel and resin do not bond, separation between these two dissimilar materials is cosmetic in nature only and in no way affecting the tank structure or operation.
  • Completed tank shall be post cure with dry heat (sunlight) following the resin manufacture’s recommendations. If repairs or rework are made following post cure, an additional post cure cycle is carried out after the repairs or rework.
  • Handling and Installation
  • Handling and installation instructions are intended to help customers install tanks correctly and efficiently.
  • Handling and installation instructions are only recommendations and they do not relieve the purchaser for proper inspection, handling and installation.
  • Improper handling or installation resulted in tank damages or failure, are the sole responsibility of the customer.
  • Failure by the customer to comply with the handling and installation instructions will void the tank warranty.
  • The presence of Cradotex personnel or authorized representative at the installation site do not relinguish purchaser of their responsibilities.
  • Cradotex tanks are designed to withstand normal handling and installation in manufacturing.The following handling Procedure follow:-
    • At all time never roll or slide the tank. We lift the tank using crane or other approved methods.
    • During hoisting the tank, we never allow tank to swing out of control.
    • Do not allow any tools , etc. to drop or cause hard impact onto the tank.
    • Do not use any equipment inside the tank that can cause scratches or damage to the inner corrosion barrier.
    • Do not use chains or cables around tank
    • Only lift tank using designated lugs.
  • Recommended tank bottom support pad as follows:-
    • Flat Bottom Tank, will require permanent bottom support pad like a concrete slab.
    • However any support structure with sufficient strength to support the tank and contents combined weight with a resonable safety factor is acceptable.
    • Design of the support pad strength is the responsibility of the customer and must exceed tank diameter by minimum 6 inches and to within flatness of +/- 1/16 inch.
    • Ensure support pad is clean and clear of all foreign objects prior to settling tank in place.
  • Recommended tank bottom buffer pad as follows:-
    • Liquid thin mortar such as concrete, epoxy, etc, must not be used under flat bottom tanks.
    • A buffer pad between the tank support and tank bottom is recommended, flexible elastomer or a minimum two layers of 30 pounds of roofing frlt.
    • Please note that it is the customers responsibility to ensure that tank is proprely installed and any deviation in installation must be informed to Cradotex to avoid null and void of warranty.
  • Recommended pipe connections as follows:-
    • To use flexible pipe connection where ever possible.
    • When use rigid piping, it must be self spporting or any damage tank fittings will void tank warranty.
    • Ensure no metal fittings are used on FRP nipples or couplings.
  • All side bottom flange pad cut out must confirm to Cradotex pad cut out specifications and any deviation without Cradotex consent will void warranty.
  • Tanks standard hold down lugs are provided by Cradotex except for hold down hardware from customer. Cradotex recommend to use two nuts on the top of each lug. To hand tighten empty tank first nut to jam the bottom nut and further tighten by using two wrenches to lock the top nut to bottom nut. Do not adjust after tank is filled. Cradotex is not responsible if pre-set anchor holes or bolts do not fit if installed before delivery of tank. Please consult Cradotex if you have questions