90 Year Old Cast Iron Lake Discharge System

KHIA ID: 8146

Industry: Fluid Flow (FLOW)
Application: VPF-Valves, Pipes and Fittings (VPF)
Substrate: Cast Iron

Customer Location: Ft. Worth Texas
Application Date: Nov 2019

Products:
Belzona 5831ST

Belzona 5811

Problem: There was no way to replace the old bonnets, valves and pipe without bringing in a crane to take the old bonnets up 100ft to the top. The customer would have had to build a special way to bring them through the vertical tunnel without damaging the 90yr old concrete which could have weakened the structure. Customer needed a solution to keep the existing valves, bonnets and pipes in place for several years to come. The age of the cast iron and the environment had created heavy corrosion in the area.

Photograph Descriptions

1. Bonnets, valve bodies and pipe prior to Blasting

2. Bonnets prior to blasting

3. Bonnets coated

4. Valve bodies and pipe coated.

Application Situation

Cast iron discharge valves, bonnets and pipe were built in the 1930's. System is located 100ft underground, has temperatures swinging from low 50F to 65F, confined space and continuous running water from the lake discharging into the pipe and valve system during application.

Application Method

Application was carried out by abrasive blasting the cast iron to SSPC SP10, whilst keeping a heater running in the area to keep the temperatures in the mid 60's f (>15c), raising the temp of the material to between 68-70F (20c to 21c) for the Belzona 5811. The first coat was applied, a second coat was applied within 24hrs to ensure proper coverage on the valve bodies. On the bonnets and pipe, Belzona 5831ST was applied whilst controlling the running water in the pipe with a makeshift dam. On the bonnets that were sweating, the surface was grit blasted and dried before applying Belzona 5831ST immediately.

Belzona Facts

Customers alternative was to replace the system at a cost of well over $1M. The Belzona solution with surface preparation and coating application was under $100k saving the customer money and time. Application was completed in under 12 days. The customer chose Belzona because of the products performance, and ease of application. The customer also chose Belzona because of their history of success in stopping corrosion long term.

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