Offshore Engineering Checklist for Nozzle Orientation

Further to my post related to requirements for preparation and issue of nozzle orientation, here is a checklist for the nozzle orientation.

Project Name:		Job No:
Equipment type:	HORIZONTAL/ VERTICAL	Equipment Tag No.:

SL NO.	DESCRIPTION
Check Points
	Common for Horizontal or Vertical Vessel
1	Vessel modelling is completed and nozzle orientation is extracted from model & checked against latest vendor drawing.
2	30% Model review is completed and review tag related to subject vessel are closed.
3	Plant “North” is indicated. Nozzle orientation angle shall be w.r.t. north as ‘0’ degree(clock wise).
4	Any P&ID notes regarding particular nozzle location/ elevation/ orientation are taken into consideration.
5	All nozzles are shown as per P&ID and are designated with nozzle tag number, size and rating. Any mismatches are commented and resolved.
6	All nozzles are shown as per Mechanical Data Sheet(MDS) and are designated with nozzle number, size and rating. Any mismatches are commented and resolved.
7	All level instrument nozzles are shown as per Level Sketches. Any mismatches are commented and resolved.
8	Vessel dimensions OD (or ID & thk) and height/ length are shown.
9	Holds & notes are clearly listed & identified with cloud.
10	All reference drawings (P&ID / MDS / Level Sketches / Vendor GA) including revision number are listed in reference drawing section .
11	Nozzles projected above platforms have minimum clearance of 150 mm between bottom of flange and top of grating.
12	Inlet and outlet nozzles shall be located sufficiently away to avoid vortex flow.
13	All nozzle projections are shown with respect to TAN line for all dish end nozzles.
14	All nozzle projections (exclusive of dish end nozzles) are shown with respect to vessel centre line for all shell nozzles.
15	Insulation thickness of vessel is considered in determining the nozzle projection.
16	Insulation thickness shall be shown dotted in drawing.
17	Proper access and approach ladder is provided for all Nozzles/ Instruments as per project specification and all Platform dimensions, location & ladder location are shown.
18	Side entry from ladder has been provided to the top and intermediate platforms.
19	All valves are accessible from ladder for size less than or equal to 3” and from platform for sizes greater than 3” unless otherwise specified in relevant project specifications/ client operation and maintenance requirements.
20	Maximum height of ladder, without mid landing is checked with respect to project specifications.
21	Location and orientation of pipe support cleats are clearly shown.
22	For Instrument nozzles that require access, check the possibility of combining the nozzles for common access and also check for any obstruction in the surrounding.
23	Hand hole location/orientation shall be shown.
24	Nozzle schedule table (showing sl.no, nozzle name, rating, size, nozzle function, nozzle projection from vessel centre line etc.) shall be shown.
25	Manhole location shall be shown. Manhole cover can be opened without any hindrance. Manhole davit orientation is marked and manhole envelope angle are shown. Sideways location is preferred manhole location.
26	Manhole height from platform shall be as per project specifications/ client requirements.
27	Orientation of skirt openings are shown
28	Minimum 750 mm clear space is available on all vessel Platforms for ease of access even after installing all Stand pipe, valves, Instruments.
	Horizontal Vessel
1	One plan view with minimum two elevation views (front view & side view) are shown, if nozzles are on both Dish end, Both views are required, The views are clearly marked with A-A, B-B etc.
2	Vessel Bottom elevation is as per P&ID(If specified in P&ID)
3	Height of centre line of equipment with respect to bottom of saddle is shown.
4	Proper access, clearances are provided for bottom nozzles, boot mounted nozzles and nozzles are clash free with equipment support.
5	Slope in Sloped vessels is shown appropriately as per P&ID requirement.
6	Slope in Sloped vessels is shown appropriately as per Mechanical Data Sheet(MDS) requirement.
	Vertical Vessel
1	One elevation view and multiple plan views at every platform elevation are shown.
2	Vessel Bottom Line elevation is as per P&ID(If specified in P&ID).
3	Based on Drop zone area, Pipe davit radius is marked. Pipe davit orientation is shown in the plan view of the top platform. Drop zone area to be accessible from common access.
4	Platform width start angle and end angle are shown clearly.
5	Orientation of pipe supporting cleat of vessel is shown.
6	When there are two platforms one above the other(typically in columns etc.), ensure adequate headroom is available and space is not obstructed due to structural bracings.
	Pig Launcher
1	Kicker line connection shall be shown on side/ top of major barrel near to end closure.
2	Balance line connection shall be shown on side/ top of minor barrel near to pig trap valve location.
3	Vent connection shall be shown on top of major barrel.
4	Pig signaler shall be located on top of minor barrel near to reducer.
5	Pressure transmitter connection shall be located on top of major barrel.
6	Pressure safety valve location shall be shown on top of major barrel.
7	Purge connection shall be located on top of major barrel.
8	Pressure indicator connections shall be shown on the top of major barrel near to end closure and also on minor barrel near to pig trap valve location.
9	Lifting lug(two nos.) location shall be shown on major barrel .
10	Drain shall be shown on bottom of major barrel near to reducer and also on bottom of minor barrel near to pig trap valve.