Skip to main content

Posts

Chain conveyor troubleshoot guide

  Problem Identification & Corrective Action Sl No. Problem Potential Cause Solution 1 Chain rises off from sprocket 1.Excess chain slack. 2.Excess wear at the bases of sprocket teeth. 3.Excess chain extension. 4.Foreign material stuck to the bases of sprocket teeth. 5.Reverse rotation of conveyor 6.Uneven chain tightening of chain 1.Adjust the amount of slack equally at both sides. 2.Carryout hard facing of the sprockets 3.Replace the elongated chain parts. 4.Remove the foreign material from the bases of the teeth. 5.Avoid reverse rotation of the conveyor when chain tightened is uneven 2 Chain separates poorly from the sprocket. 1.Sprocket misalignment. 2.Excess chain slack. 3.Excess wear at the bases of sprocket teeth. 4.Uneven chain tightening of chain 1-Adjust alignment. 2-Adjust the amount of slack.
Recent posts

Comparison between Acetylene & LPG fuels for gas cutting operation

  SL No. Acetylene LPG (Propane) 1 Highest flame temperature up to 3100 Deg C Flame temperature up to 2800 Deg C 2 Flame speed up to 7.5 m/sec Flame speed up to 3.3 m/sec 3 Most of the heat released is in inner cone Most of the heat released is in outer cone 4 Higher flame GCV of inner cone (4500 kcal/M3) Lower flame GCV of inner cone (2500 kcal/M3) as compared to acetylene 5 Stoichiometric air fuel ratio1.2:1 (Requires 2.5 to 3 Oxygen cylinders for burning one Acetylene cylinder) Stoichiometric   air fuel ratio 4.3:1 (Requires 7 to 8 Oxygen cylinders for burning one LPG cylinder) 6 Can be used in gas welding, as acetylene when burning with air creates reducing zone that cleans the steel surface Cannot be used in gas welding as it does not c

Why do Bearings fail?

 Following are the 16- top listed reasons for bearing failure or damages 1-Lubrication: Following are the 7 major reasons for bearing failures related to lubrication 1-Lack of lubrication 2-Less lubrication 3-Over lubrication 4-Contaminants in lubricants 5-Wrong method of lubrication 6-Poor quality of lubricants 7-Selection of wrong lubrication 8-Lubricant failure 2-Bearing clearance: Bearings may fail if the clearance between rolling elements & race is too less & too more. Lesser bearings clearance than desired creates friction & temperature rise. More bearing clearance creates vibrations 3-Operating the bearings at higher vibrations for long time: Bearings can operate satisfactory at the vibrations range up to 5 mm/sec, vibrations more than this reduces the bearing life & eventually failure. Operation range: 0.5 to 3 mm/sec Alarm Range: 3 to 5mm/sec Trip range: > 5mm/sec High vibrations in machine or bearings are due to; 1-Axia

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

Why does load hunting occur in steam Turbines??

 If Turbine does not maintain the load as per set load, then this condition is called load hunting.Following are the some potential reasons for load hunting 1-Problems associated with actuators: These are related to leakages in actuators, piston stuck up, oil holes elongation etc. Because of these issues there will interruption or fluctuation of secondary oil flow through actuators, this creates the problems of actuator miss-operation & eventually load hunting. 2-Improper calibration of actuators: This results into mismatch of actuator opening & given set point or valve demand 3-Lower control oil pressure than required: Actuators are designed for specific pressure of control oil, if the control oil pressure at actuator inlet becomes less, then there will be more chances of mal function of actuator. 4-Fluctuation of control oil pressure/flow: Fluctuation of control oil pressure or flow due to malfunction of pump or line PRV may lead to actuator misoperation & h

Why does Boilers main steam temperature increase more than design?

  1-Decrease in Economiser inlet feed water temperature Upon decrease in economiser inlet feed water temperature, fuel consumption in furnace increases & hence main steam temperature increases more than desired. 2-Load on Boilers is more than design Main steam temperature increases if the steam generation is more than actual designed 3-Leakage in super heater (SH) coils If there is any leakages in SH coils, steam flow to SH coil decreases & hence main steam temperature increases. 4-Choking in Super heater coils Super heater coils Choking due to foreign materials & internal scaling due to poor water chemistry leads to less steam flow through coils resulting into higher main steam temperature due to poor heat transfer. 5-Passing of start-up vent control valve Passing of start-up control valve loads more on Boiler steam generation, hence main steam temperature increases 6-Passing or pop up of drum safety valves : Lifting of drum safety valves lead to less ste

Power plant and calculations

1- Powerplants thumb rules 2- Energy conservation in power plant 3-Calculation of PG cost in power plant 4-Steam condenser & vacuum 5-Boiler feed pumps QnA 6-Turbine practical questions & Answers 7-50-QnA on bearings 8- Power plant equipments efficiency calculations 9-Best practices to reduce power plant Auxiliary power consumption 10-Boiler safety valves QnA 11-QnA on fuel handling /belt conveyors 12-Reasons for machine vibrations 13-Thermal expansion in Boilers 14-30-things you must know about steam Turbines 15-QnA on power plant maintenance 16- 22-Questions & Answers on Boiler troubleshooting 17- HP dosing system capacity calculations 18-WTP thumb rules 19-WTP QnA 20- Power plant equipments safe preservation methods 21- Fundamental about nut bolts 22- QnA on rigging technology 23- Power generation calculations in steam turbine 24-QnA on spent wash Boilers 25-Questions & Answers on air compressors 26-Know about Valves 27- QnA on batteries 28- IBR forms, acts & Reg
close