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Why does vacuum in steam condenser reduce or drop??

  1-High exhaust temperature: Vacuum drops or maintains at lower side due to high exhaust steam temperature flow into steam condenser. This high exhaust temperature is mainly due to 1-Operation of Turbine at lower loads 2-More clearance in labyrinth seals 3-Not operating exhaust hood sprays 4-More load on condenser 5-Breaking of ejector U loop 2-Low circulating cooling water flow Vacuum in condenser reduces due to inadequate cooling water flow through steam condenser. This is mainly due to; 1-Problems associated with pumps 2-Air pockets in pipe line 3-Leakages in cooling water line 4-Stuck of discharge valve of pump 3-High cooling water temperature at condenser inlet Higher cooling water temperature at condenser inlet results into reduction of vacuum due to poor heat transfer from steam to water 4-Poor heat transfer in condenser Very less or poor heat transfer in steam condenser reduces vacuum to very low level resulting into high exhaust temperature &am

Tools tackles used in power plant maintenance


Tools & Tackles are the main resources for power plant maintenance..Thsese are classified into Hand tools,machine tools, lifting tools & measuring tools.


Power plant maintenance tools & tackles

Powerplants of capacity 10 MW to 100 MW need following tools for routine preventive, predictive & breakdown maintenance works.
A. Hand Tools:
  • Spanners (Ring, flat, box, tubular and Allen types)
  • Files (Rectangle, square, triangular, round, half round)
  • Chisels 6", 12"
  • Screw spanner 6", 12"
  • Pipe wrench 12", 24"
  • Plumb
  • Hammer and mallets
  • Pliers (Nose and circlip pliers)
  • Shim cutter
  • Torque wrench
  • Pipe bender
  • Hole and letter punches
  • Screw drivers
  • Line testers
  • Bench vice
B. Machine Tools:
  • Single phase Hand drill machine
  • Hand angle grinding machine (AG-4, AG-5 and AG-7)
  • Pipe cutting machine (Chop saw machine)
  • Air blower
  • Vacuum cleaner
  • Hot gun
  • Bearing heaters
C. Lifting/Pulling Tools:
  • Chain blocks (1T, 2T, 3T, 5T and 10T)
  • Dee shackles (1T to 10T)
  • Eye bolts (0.5T to 10T)
  • Polyester/Nylon Lifting belts (1T to 10T)
  • Chain puller (1T)
  • Pulley block (0.5T to 5T)
  • Hydraulic jack (25MT)
  • Screw jack (2T to 10T)
  • Coupling puller
  • Wire ropes (1/2" and 1")
  • Slings (1/2", 1", 1.5")
D. Measuring Tool (Instruments):
  • Vernier caliper ( 0–150 and 0–300 mm LC: 0.02 mm)
  • Measuring tape (3 meter and 5 meter)
  • Inside and outside micrometer screw gauges (0–25 mm and 50–200 mm LC: 0.01 mm)
  • Dial gauge (LC: 0.01 mm)
  • Inside and outside calipers
  • Ultrasonic thickness checking machine
  • Infra-red temperature gun
  • Tachometer
  • Multimeter
  • Clamp meter
  • Earth leakage tester
  • Earth resistance checker
  • Insulation resistance checker
  • Pressure gauge calibrator
  • Balance weigher
  • Sound level meters


Comments

  1. Please add the use of each in brief.

    ReplyDelete
  2. Please add the use of each in brief.

    ReplyDelete
  3. Your blog is very valuable which you have shared here about basic types of joints. I appreciate your efforts which you have put into this article and also it is a gainful article for us. Thank you for sharing this article here. Overall Equipment Efficiency

    ReplyDelete

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Hi all,
This article is written based on practical experience..If liked, share with others, or any suggestions leave in comment box.

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