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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.

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.

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

Clear steps for Boiler Safety valves major overhauling

 Boiler Safety valve major overhauling steps Cleaning of safety valve Complete dismantling of safety valve. Cleaning, polishing & buffing of parts. Thorough inspection of all parts. Seat & disc lapping Spindle run out (bend) checking Spring checking for any abnormalities like crack, bend, reduced tension etc Lapping of both disc & seat. Inspection of upper & lower ring teeth for damage/crac Measurement & re-assembly. Inspection of discharge pipe connection. If there is telescopic discharge pipe, then ensure a gap of minimum 10 mm for thermal expansion. ASSEMBLY STEPS. 1-After seat & disc lapping, place lower nozzle ring on seat & level both the faces Questions & Answers on Safety valves 2-After leveling, turn the lower ring by 3 notches in clockwise direction. For example if Safety valve’s operating pressure is 117 kg/cm2, then 117 kg/cm2/42.4 kg/cm2 = 2.75 Appx. 3 Nos i.e 42.4 kg/cm2 for every notch (For more details, refer

Turbine oil and transformer oil standard testing parameters

  TURBINE OIL STANDARD PARAMETERS OIL: Servo prime 46T Testing frequency: Every 6 months Sl No. Oil Property UOM Test Method Acceptable limits 1 Appearance NA Visual Clear/yellow Viscous liquid 2 Colour Hazen ASTM D1500 < 2 3 Density Kg/m3 IS 1448-P-16:1990 820-870 4 Flash Point 0 C ATM D 93 > 180 5 Kinematic Viscosity at 40 0 C Cst ATM D 445-17a 43-48 6 Kinematic Viscosity at 100 0 C Cst ATM D 445-17a >6.7 7 Viscosity index NA ASTM D 2270 > 98 8 PRPVOT (Revolving Presure Vessel Oxidation  Stabilty Test)
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