Just like a new vessel is made, a reglassed vessel is produced with an impermeable surface finish that achieves an optimum balance of corrosion resistance, thermal properties and mechanical strength. It takes about 10 weeks from start to finish.
Here are the steps it takes to get there:
Upon receipt at our facility in Corpus Christi, Texas, the vessel is examined, and inspection details are carefully documented. Once the initial inspection has been completed, DDPS will determine whether to proceed.
If the vessel has a jacket, the jacket will be removed, and a second external inspection is performed to check the condition of the steel. This step is critical to ensure that the steel shell of the reactor body is in a usable state.
Both the inner chamber and jacket are grit-blasted. This process involves using a forced stream of abrasive material against the glass surface as well as the exterior of the vessel to remove all glass, paint, and any oxidation that has built-up over years of use and exposure.
Inspection after Blasting
The inside of the vessel and jacket are examined again to determine the extent of base-metal corrosion. Ultrasonic testing is performed to measure the thickness of the base metal.
Proceed with Repairs
Weld repairs are made to the inner vessel and the jacket (if jacketed). This step can vary greatly in time and intensity, as the condition of the vessel can significantly impact the level of repairs required to get it in satisfactory condition for the glassing procedure. In addition to repairs, this is also the time that upgrades can be made to your vessel, including OptiMix baffles, extra nozzles and insulation rings.
Preparation for Glass Lining
The steel surfaces are prepared for glassing, including grit blasting. This smooths the steel surface and gets it ready for the first coat of glass, known as the ground coat. This base coat has limited corrosion resistance but is important in developing a chemical bond between the subsequent glass layers and the base metal.
Glass Lining Application
The glass lining process is exactly the same as the procedure for fabricating a new vessel. In short, the vessel interior is sprayed with glass, dried, fired, and cooled. The cycle is repeated until the desired glass thickness is attained.
After glass lining is complete, the jacket, which has undergone repairs, is ready to be installed (welded) to the vessel.
This is a common test performed in pressurized equipment to test for strength and leaks. It involves filling the vessel or jacket with water, pressurizing the equipment to the maximum pressure allowance, and observing if there is pressure loss or leakage. The jacket is always hydrostatically tested; the inner vessel will be tested only if major code repairs or alterations were done.
Prepare for Shipment
After the hydrotest, the vessel is painted and then prepared for shipment. To signify that the vessel meets applicable codes, a new nameplate with an "R'' stamp will be attached to the vessel next to the original nameplate.
At this point you are about to receive a truly “like new” vessel. The warranty on a reglassed De Dietrich vessel carries the same warranty as a newly fabricated vessel!