Questions related to Pump/ Alignment/ Alignment/ pump piping Posted by: admin by: admin 13 13 hours ago in Blog in Blog Comments Off
1. What are different types of pumps? Answer: – Basially there are two types of pumps! A! Centrifugal Pump! B! Positi"e #isplaement pump! 2. What are the different types of centrifugal pump? Answer: – #ifferent types of Centrifugal Pump are: – A! $ingle $tage or B! %ulti&stage 3. What is the basic difference between single stage and multi-stage centrifugal pump? Answer: – 'he $ingle stage pump has one impeller and multi&stage pump has two or more impellers in series! 'he disharge of one impeller is the sution of the ne(t one and the head de"eloped in all the stages are totaled! 4. How many types of centrifugal pump are available based on the uction and !ischarge arrangement? Answer: – Based on the sution and disharge arrangement) the type of entrifugal pumps a"ailable is: – A! *nd $ution 'op 'op #isharge! B! 'op $ution 'op #isharge! C! $ide $ution $ide #isharge! ". What are the different types of casing? Answer: – Casings are generally of two types: "olute and irular! 'he impellers are fitted inside the asings! #. !efine the wor$ing mechanism of centrifugal pump? Answer: – A entrifugal pump is one the simplest piees of e+uipment in any proess plant! ,ts ,ts purpose is to on"ert energy of prime mo"er -an eletri motor or turbine. first into "eloity or ineti energy and then into pressure energy of a fluid that is being pumped! 'he energy hanges our by "i rtue of two main parts of the pump) the impeller and the "olute or diffuser! 'he impeller is rotating part that on"erts dri"ers energy into the ineti energy! 'he "olute or diffuser is the stationary part that on"erts the ineti energy into pressure energy! %. How the $inetic energy created by centrifugal force is converted to pressure energy? Answer: – 'he energy reated by entrifugal fore is ineti energy! 'he amount of energy gi"en to the li+uid is proportional to the "eloity at the edge or "ane tip of the impeller! 'he faster the impeller re"ol"es or the bigger the impeller is then the higher will be the " eloity of the li+uid at the "ane tip and the greater the energy imparted to the li+uid! 'his ineti energy of the li+uid oming out of an impeller is harnessed by reating a resistane to the flow! 'he first resistane is reated by the pump "olute -asing. that athes the li+uid and slows it do wn! ,n the disharge no00le) the li+uid further deelerates and its "eloity is on"erted to pressure aording to Bernoullis priniple! 'herefore) the head -pressure in terms of height of the li+uid. de"eloped is appro(imately e+ual to the "eloity energy at the periphery of the impeller e(pressed by the following formula as: – 2 "4/ 4g 5here) 2 'otal head de"eloped in feet! 6 6eloity at periphery of impeller in ft/se! 7 Aeleration due to gra"i ty&34!4ft/se4 8ormula for alulating peripheral "eloity: 6 9 # 44; 5here) 6 Peripheral "eloity in impeller in ft/se! 9 'he impeller rpm -
?? ft3 of "apor at the same temperature! 'he "apori0ation begins when "apor pressure of the li+uid at the operating temperature e+uals the e(ternal system pressure) whih in an open system is always e+ual to atmospheri pressure! Any derease in e(ternal pressure or rise in operating temperature an indue "apori0ation! 'he "apor pressure ours right at the impeller inlet where a sharp pressure drop ours! 'he impeller rapidly builds up the pressure) whih ollapses "apors bubbles ausing a"itation and damage the pump internals! 'his is a"oided by maintaining suffiient 9P$2! -Ca"itation implies a"ities or holes i n the fluid we are pumping! 'hese holes an also be desribed as bubbles) so a"i tation is really about the formation of bubbles and their ollapse! Bubbles form whene"er li+uid boils! ,t an be a"oided by pro"iding suffiient 9P$2!.
Questions related to wrapping @ oating/ insulation/ athodi protetion: &Part&1 Posted by: admin 1> days ago in Blog Comments Off
1. What is the procedure for application of wrapping and coating? Answer: – Proedure for appliation of Coating and wrapping: – A! Prior to appliation of wrapping @ oating) the surfae of pipe should be made free from all loose %ill sale) dirt) rust) grease) moisture and other foreign material! 'his is ahie"ed by blast leaning to grade $a 4 ! B! 'he pipe e(terior surfae or blast surfae shall be oated with primer within four hours of shot C and blasting! 'he primer shall not be applied when the pipe surfae temperature is below > C! when moisture is present on the surfae) the same is heated for suffiient time to dry abo"e >? the surfae! C! 'he pipe after priming shall be oated with two&flood oat of hot enamel inorporating the simultaneous appliation of inner @ outer wrapping! 2. What is the content of primer applied on the pipe surface before coating? Answer: – 'he primer onsists of proessed oal – tar pith and refined oal – tar oil! 3. What is the enamel applied on the pipe surface for coating? Answer: – 'he enamel is plastiised oal tar pith sui table for hot appliation and filled with inert mineral filler whih ha"e minimum tendeny to settle down in fluid state! 4. Which material is used as inner and outer wrapping? Answer: – 8ibre glass tissue onsisting of a uniformly porous mat of hemially resistant boro – sili ate glass ontaining not less then B4O3! ". What should be the minimum thic$ness of enamel on any point on pipe? Answer: – 'he enamel shall ha"e minimum thiness of 4!D mm when measured on top of the weld with an o"erall thiness of Dmm! #. How much should be the depth of pulling of inner )ibre * glass tissue into the hot enamel? Answer: – 'he inner wrap of 8ibre – glass tissue pulled in suh a manner that the same is imbedded half way into the enamel without touhing the steel surfae! %. What should be the overlap between inner + outer wrap? Answer: – 'he inner and outer wraps shall be o"erlapped by 4mm! &. What should be the minimum staggering of inner + outer wraps, Answer: – 'he o"erlaps of the inner and outer wraps shall be staggered from eah other by minimum distane of 1??mm! . What is cold type of wrapping? Answer: – P6C baed bituminous ompound tape used for field wrapping is alled old wrapping! 1. What is the minimum overlap of field wrapping /cold 0ape on shop wrapping? Answer:&5 rapping shall start and finish to gi"e a minimum >mm o"erlap onto the ad=oining shop oating! °
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Questions related to wrapping @ oating/ insulation/ athodi protetion& Part&4 Posted by: admin 1? days ago in Blog Comments Off
11. What is the material applied on the flanges or valves to obtain smooth surface for application of cold 0ape? Answer: – %oulding ompound shall be hand applied to obtain the smooth surfae for appliation of old tape on flanges / "al"es! 12. What is the device used to locate the defects on surface of coating + wrapping? Answer: – 2oliday #etetor! 13. How much crest voltage of Holiday !etector shall be set? Answer: – 'he rest "oltage of 2oliday #etetor shall be set as high as pratial! 14. What is the test to ensure the proper thic$ness adhesion and the position of inner wrap? Answer: – A s+uare of 4mm 4mm shall be ut from wrapping for determination of thiness) adhesion and position of the inner wrap! 'his shall be arried out at the r ate of one pipe per ? oated! 1". What are different types of nodes used in cathodic protection? Answer: – #ifferent types of Anodes are %agnesium) Ein) 2igh $ilion ,ron) Aluminum et! 1#. What are nsulating 5as$et 6its? Answer: – ,nsulation gaset its are designed to restrit the effets of orrosion often found in flanged pipe
systems! 'he most ommon e(ample is fire water line running inside the ground and turned upward on abo"e ground with flanged onnetion! ,t onsists of following its: – A! 7aset : – 9eoprene faed Phenoli /7lass mm thiness and double layer at ;?mm thiness and greater! 21. What care shall be ta$en before applying insulation? Answer: – 'he surfae to be insulated shall be free from oil) grease and all other foreign matter and shall be free from moisture prior to the appliation of any insulation! °
Question related to 9on& destruti"e 'esting Posted by: admin 4? days ago in Blog Comments Off
1. !escribe different types of destructive and non-destructive tests? Answer: – #*$'
