P-03 MAINTENANCE MECHANIC TRAINING SKILL DEVELOPMENT GUIDE Duty P: Steam Systems P-03: Perform Startup and Shutdown Procedures Issued 01/01/99
Perform Startup and Shutdown Procedures Task Preview Startup and shutdown procedures are performed to turn on and off the steam and condensate used for heating during an emergency, to start or end the cold season, or to shutdown or startup the process steam during repairs. The purpose of shutting down the steam after the cold season is to save energy or provide maintenance to the heating system. The only time the process steam is shutdown is to provide maintenance to the process steam system. Startup and shutdown procedures are performed at the main gate valve where steam from the powerhouse originates in the plant. The Maintenance Mechanic and an assistant familiar with steam processes should perform startup and shutdown procedures. The Maintenance Mechanic must know basic pneumatic principles, various pneumatic component operations, and have good communication skills. If this task is performed incorrectly or incompletely damage to equipment, personal injury or even death may result. Performing this task requires informing the required personnel about shutting down or starting up the steam system. Visual and physical verification of the operation of the various valves, traps, etc. in the system. Communicate with the powerhouse to inform them of startup/shutdown. Crack the bypass and allow the steam to build up slowly. Visually/physically check various points in the system for normal operation. Bring the bypass pressure up until the valve is opened completely. If pressure is holding steady and condensation pump is operating normally, crack the gate valve. Control the pressure from the controller and slowly bring pressure up to normal operating pressure. How your skills will be checked The Skill Check will require you to perform startup and shutdown procedures. All tools, materials, and resources will be available. The Evaluator will verify that your demonstration meets the skill objective by observing or measuring each task standard. You must demonstrate safe work practices during the Skill Check. Contact your Evaluator when you are ready for the Skill Check. Skill Development Guide 2 P-03: Perform Startup and Shutdown Procedures
Skill Objective Given an operating or a shut down steam system, perform startup/shutdown procedures. Task Standards 1. Steam system must be shut down so that no pressure is built up on the controller valves when performing the shutdown procedures. 2. Steam system must be built up so that the incoming pressure gage reads approximately 250 psi when performing startup procedures. 3. Steam system must be built up so that the first controller pressure gage reads approximately 100 psi when performing startup procedures. 4. The steam system must be built up so that the second controller pressure gage reads approximately 50 psi when performing startup procedures. Skill Development Guide 3 P-03: Perform Startup and Shutdown Procedures
What You Will Need This section contains the safety information, tools, and resources you will need before performing startup or shutdown procedures. Follow all Caterpillar facility safety standards when performing this task. Shutting down steam requires lock and tag. Lift/man trucks (JLG) may be required to reach various steam components. Exercise extreme caution, steam temperatures can reach 406ºF at 250 psi, starting up the steam pressure too fast can result in death. basic Maintenance Mechanic hand tools pipe wrenches packing glands 8 to 10 valves print, if available (plant pneumatic/steam layout) Skill Development Guide 4 P-03: Perform Startup and Shutdown Procedures
Perform Startup and Shutdown Procedures Perform Steam System Startup Task Steps 1. Verify that the various plant steam systems are prepared for startup. This procedure may take an entire day. Check the heating stations under the roof to verify they are ready for startup. Communicate with the various personnel to inform them that you are preparing to start up the steam system. Visually and physically check the various valves and components verifying that they are opened and ready for the steam to be turned on. Verify that the gate valve is shut off. Gate Valve Gate Valve Shutoff Verify the controller valves are functioning according to manufacturer s specifications and are left in the open position. Skill Development Guide 5 P-03: Perform Startup and Shutdown Procedures
Connect hoses to the end of each main header to collect condensate during initial startup. This prevents hammering of the steam lines. The small traps will not handle the volume of condensate at the initial startup. 2. Communicate with the powerhouse. Let the powerhouse know that you are turning on the steam system. Maintain communication with the powerhouse. You can only supply steam as fast as the powerhouse provides it. You will need to let the system build up pressure. Warning: Be prepared to turn down the system if loud clanking and bumping noises are heard in the system. Flashing may occur if the pressure is brought up too fast, causing injury to personnel or damage to equipment. 3. Slowly open the bypass valve to preheat the system. Bypass Valve Preheat with the Bypass Valve Turn the bypass valve wheel 1/8 to 1/4 turn until you feel and hear the steam begin to flow through the system. Opening the bypass completely may take a few hours to let the steam build up completely. Skill Development Guide 6 P-03: Perform Startup and Shutdown Procedures
Walk to the first trap in the system, listen for steam, and feel for a warmer temperature change. Trap Trap Location Open the bypass valve a little bit more (1/4 turn) as the system warms up. 4. Check the operation of the nearest condensation pump. Make sure the pump is running. Skill Development Guide 7 P-03: Perform Startup and Shutdown Procedures
Visually verify water in the condensation glass. Condensation Sight Glass Condensation Pump Feel the pump for temperature increase. 5. Return to the bypass valve and further increase the pressure. Continue to observe the system operation. Listen for disturbances in the system. Slowly increase pressure from the bypass valve until it is fully open. 6. Walk to the farthest trap from the gate valve and feel for an increase in temperature. Check the various traps in the system as you walk to the farthest trap. Make sure there are no leaks, plugs, or other problems in the system. Skill Development Guide 8 P-03: Perform Startup and Shutdown Procedures
7. Prepare to open the gate valve. Close the second controller valve. Open or Close Controller Valve Inside this Box Controller Valve No. 2 Controller Valve No. 1 Skill Development Guide 9 P-03: Perform Startup and Shutdown Procedures
8. Crack the gate valve. Slowly pull the chain to turn the gate valve 1/8 to 1/4 turn. Slowly Pull the Gate Valve Chain Do not close the bypass valve until the steam system is up to operating pressure. 9. Control the pressure from the second controller valve. Slowly open the controller valve allowing the pressure to build up. Maintain a balance between the controller pressure and the amount of pressure coming in from the gate valve. Remember, the powerhouse can only supply so much pressure, so allow the steam to build up. Do not let the system starve for pressure; keep the condensation buildup moving to avoid flashes. 10. Continue to monitor the various components in the plant steam system. Be prepared to shut down the pressure in the event of an emergency. Skill Development Guide 10 P-03: Perform Startup and Shutdown Procedures
11. Continue slowly opening the gate valve and controller valve until the gate valve is providing normal operating pressure. The pressure coming to the gate valve should be approximately 250 psi, according to the powerhouse pressure at that time. 100 200 250 PSI Incoming Pressure 0 PSI 300 Skill Development Guide 11 P-03: Perform Startup and Shutdown Procedures
The pressure after the first controller must be about 100 psi. 100 100 PSI Pressure After Controller Valve No. 1 0 PSI 200 Skill Development Guide 12 P-03: Perform Startup and Shutdown Procedures
The final pressure, after the second controller, into the plant must be about 50 psi. 50 50 PSI Pressure After Controller Valve No. 2 0 PSI 100 Shut Down Steam System 1. Communicate with the powerhouse. Let the powerhouse know that you are turning off the steam system. Maintain communication with the powerhouse. 2. Perform lockout/tagout. Turn off the gate valve. Attach your lock and tag to the gate valve. 3. Perform the required maintenance, as required, if process steam. Follow the steps to turn the steam on. The system may not need to be warmed up if the system was not shut down for a lengthy period of time. Skill Development Guide 13 P-03: Perform Startup and Shutdown Procedures
Perform Startup and Shutdown Procedures Concept Check Answer the following questions to check your understanding of performing startup and shutdown procedures. Circle the correct answer in each question. Then compare your responses with the answers at the bottom of this page. Some of the questions may have more than one correct answer. If you have difficulty answering a question, review the Skill Development Guide or ask your Trainer for assistance. 1. The purpose of shutting down the steam after the cold season is to save energy or provide maintenance to the system. a. machine b. conveyor c. heating d. cooling 2. The only time the steam is shut down is to provide maintenance to the system. a. process b. heating c. cooling d. building 3. Startup and shutdown procedures are performed at the: a. trap. b. first controller valve. c. second controller valve. d. main gate valve. Skill Development Guide 14 P-03: Perform Startup and Shutdown Procedures
Answers: 1. c 2. a 3. d Next Step If you are ready to demonstrate the task now, ask your Evaluator or Trainer to schedule the Skill Check. However, if you need to practice some of the steps first, continue to the next section. Skill Development Guide 15 P-03: Perform Startup and Shutdown Procedures
Practice The following practice will help prepare you for the Skill Check. Ask your Trainer to set up the practice for you. After you complete a practice, ask your Trainer to check your work. Practice Identify the various components and required pressures in the process and heating systems. Practice Objective The Trainer must agree that all components and pressures in the system are correctly identified. Next Step Continue to practice until you are ready for the Skill Check. When you are ready to demonstrate the task, ask your Evaluator or Trainer to schedule the Skill Check. Skill Development Guide 16 P-03: Perform Startup and Shutdown Procedures