PART-20- 📚📚-CSWIP 📚📚 QUESTION WITH ANSWER (WELDING AND QC INSPECTOR INTERVIEW QUESTIONS)

8. What are the basic principles of locating the Equipment irrespect of the type of

arrangement?

Answer :-

 The certain basis principles to be followed while locating the equipment is as :-

 A. Economics piping:

 In order to minimize the cost of piping, the equipment should be located in process

 sequence and close enough to suit safety needs, access requirements and flexibility. The

 equipments are identified which forms the subsystem within the unit. The component

 within the subsystem to be arranged to have most economical piping and the whole

 subsystem to be arranged within the unit to have most economic interconnection.

 B. Process Requirement :

 The equipment layout should support requirement like minimum pressure drop, gravity feed and loop.

 C. Common operation :-

 The equipment that requires common maintenance facilities, common utility and

 continuous operator attention shall be located the same area.

E.Underground Facilities :

Before deciding the equipment location, the facilities such as storm water drain, effluent

drain, fire water, cooling water to be placed underground.

9. What is Line Routing Diagram?

Answer :-

 A line routing diagram is a schematic representation of all process and utility – piping system drawn on a copy of plot plan. This diagram does not show the exact locations, elevations or interference but it locates the most congested area.

10. How do you calculate the width of pipe rack?

Answer :-

Answer :- 

 W = (f x n x s) + A + B 

 …… Where f : Safety Factor 

 = 1.5 if pipes are counted from PFD. 

 = 1.2 if pipes are counted from P & ID. 

 n : number of lines in the densest area up to size 450NB 

 = 300 MM (Estimated average spacing) 

 = 225 mm ( if lines are smaller than 250 NB) 

 A = Additional Width for :- 

 : Lines larger than 450 NB. 

 : For instrument cable tray / duct. 

 : for Electrical cable tray. 

 s : 300 mm (estimated average spacing) 

 : 225 mm (if lines are smaller than 250 NB) 

 B : future provision 

 = 20% of (f x n x s ) +A 

16. What care shall be taken while routing piping for instruments ?

Answer :-

 Following points shall be taken care of while routing piping for instruments.

 A. Flow measuring instrument needs certain straight length on upstream & downstream of the instruments. Normally, 15D on the upstream and 5D on the downstream is

kept.

 B. The pipe line in which flow meters such as magnetic flow meters, vortex meters,

turbinemeters etc are located shall be routed in such a way that the line must be filled with

liquid all the time. The pipe line shall be supported with robust support on both side of the meter.

 C. Control valves are located at grade e. g. at about 500mm height from finished

ground to provide convenient access for operation and maintenance. Block and bypass valve shall be located to have easy operation /access from the grade. Locating control valve on the vertical line shall be avoided.

 D. Isolation valves for level gauges and pressure gauges shall be made accessible.

All primary and secondary indicators of pressure, temperature, flow, level, petitioners etc shall be visible from the operating area.

 E. Rotameter shall be placed on vertical line and the inlet shall be from the bottom

of the instrument.