A step-by-step guide to prepare your boiler for inspection
Preparing the boiler for inspection can be intimidating, as there are so many things to be mindful of. One small mistake can lead to malfunction. Therefore, it’s essential to understand all the necessary steps before beginning the procedure.
Regular boiler inspections are crucial to ensure the safe and proper operations of all its components and equipment. It’s vital to reduce the thermal stress with adequate procedures when proceeding to detach the boiler from the service. It would be best if you also were mindful not to allow the settling of smudge on waterside surfaces.
One of the most important things to keep in mind is not to try to cool the boiler quickly. If it cools down rapidly, the stress caused by the vigilant expansion and contraction can result in leaks on the rolled tube ends. It can also harm the firebrick and damage the refractory material.
Quick draining and cooling can also lead to the formation of suspended solid particles in the water of the boiler. These solid particles can be quite challenging to remove from the boiler. They also hinder the heat transfer mechanism and can lead to inaccurate interpretations of the treatment program.
Therefore, it’s necessary to incorporate practices of industrial boiler services. Due to these peculiarities, the preparation process needs to be handled with the utmost care and diligence. Follow our thorough and step-by-step guide below.
Step 1: Prepare the boiler for shutdown
To prepare your boiler for shutdown, you’ll have to coordinate with a lot of people. Follow the steps give below to ensure maximum safety and efficiency:
- Decide on a shutdown time for the boiler that will have minimum impact on operations.
- Ensure availability of the boiler operator along with the maintenance personnel to run any necessary testing and evaluation of safety and operating tools.
- When you have scheduled the shutdown time, make sure you notify all the production, operating, and maintenance staff about the date and time of the shutdown.
- Make sure you also notify the water treatment company and the assigned boiler inspector.
- Ask the inspector for any additional requirements or preparation tips.
- Study the boiler operating manual for instructions on any specific shutdown steps and procedures for your boiler.
- Keep the current inspection certificate of your boiler on site.
- Increase theblowdown rate of the boiler by 10% – 20% and the bottom blowdown rate by 50% a couple of days before the shutdown.
- Simultaneously, regulate the alkalinity level at the maximum end of the control range while increasing the volume of supplemental dispersants by half.
- Implement lockout procedures for water, fuel valves, steam, electrical disconnects, ignition system, and any other hazardous factors.
- Keep the boiler room clutter-free, remove all the debris from the boiler to ensure that the inspector would have convenient access to all the equipment.
- Keep new gaskets available for every opening.
Step 2: Cool down the boiler
In order to ensure the safe cooling down of the boiler, follow the instructions given below:
- As soon as the boiler is shut down, you need to begin heavy surface blowdown. Make sure the bottom blow is performed frequently, going through each gauge glass separately.
- For the replacement of the water blowdown, don’t use cold makeup. Hot feedwater is a better and safer alternative.
- When the boiler is cooling down, keep the heavy surface blowdown going.
- To control the thermal stress, make sure that the rate of cooling doesn’t go beyond 100F per hour.
- To avoid creating a vacuum when the boiler pressure goes below 5 to 10 psi, open a vent valve until all the steam is out—vacuums damage gaskets and gauges.
- Open the drain valves to drain out the boiler.
Step 3: Washout the boiler
After the cooling step, the boiler needs to be washed out. Follow the instructions given below:
- After draining the boiler completely, remove covers of the handhole and manhole to facilitate the inspection process.
- Perform a quick inspection of the boiler before the sludge deposits dry out.
- Observe and take notes of color or deposit thickness patterns, if any. It will help you understand the reason for deposit formation and the preventive measures required for it.
- After the inspection, use a high-pressure water hose to wash out the waterside surfaces. Consult your boiler inspector for this specific step because the procedure would depend on the type of your boiler.
Firetube boilers: For firetube boilers, you’ll have to begin the washout from the top manhole, then go down to the lower and side sections by using the handholes. Inspect the boiler bottom and wash it out in a way that no buildup is left.
Watertube boilers: For watertube boilers, you’ll have to first wash out the steam drum. Take out all the plates and steam separators that might be blocking access to the tube. Washout the tubes separately to remove all blockage. Before putting the boiler back in service, make sure all blockages are removed to prevent tube failure and overheating.
- Thoroughly wash out the bottom blowdown lines to ensure that no obstructions, blockages, or partial blockages are left.
Conclusion
To ensure the efficient operations of boilers, it’s absolutely necessary to get them inspected regularly. Industrial steam boiler maintenance is an essential practice that should be carried out by professionals.
If you need assistance in maintaining high-efficiency operations of your boiler and other energy systems, then contact our highly experienced team at Campbell-Sevey. We pioneer peak efficiency operations and optimized cost controls.
Our highly-efficient commercial HVAC solutions and boiler maintenance services have satisfied thousands of clients over the years.
Contact us today to help you prepare your boiler for an inspection!