Inflection Point Engineering Section 4 — Structures and Foundations

Auxiliary Structures for Operation and Maintenance

IPE Engineering Practice IPE-EP-4-5-3

Document number: IPE-EP-4-5-3 · Section: 4 — Structures and Foundations

Figure 12 Ladder Safety Gate 37

Figure 13A Typical Handrail Detail 38

Figure 13B Removable Handrail Section Detail 39

Figure 14A Typical Handrail , Floor Plate and Grating Connections 40

Figure 14B Typical Handrail, Floor Plate and Grating Connections - Continued 41

Figure 15A Floor Grating Arrangement In Structures - Plan View 42

Figure 15B Floor Grating Arrangement In Structures - Sections 43

Figure 15C Floor Grating Arrangement In Structures - Cutout Reinforcement 44

Figure 16 Stair Details - Grade to Platform 45

Figure 17 Stair Details - Platform to Platform 46

Figure 18 Stair Stringer Details 47

Figure 19 Stair Tread Detail 48

Figure 20A Wooden Crossover - Elevation 49

Figure 20B Wooden Crossover - Detail and Sections 50

Figure 21 Concrete Figure 51

Figure 22A Steel Crossover - Elevation 52

Figure 22B Steel Crossover - Plan and Detailstank Ladder Figure 53

Figure 23 Tank Ladder Details 54

Figure 24 Railing at Foam Chambers for Fixed Roof Figure 55

Figure 25 Wing Railing for Fixed Roof Figure 56

SCOPE

2.0 REFERENCES

The latest edition of the following standards and publications are referred to herein.

STANDARDS AND PUBLICATIONS

IPE Engineering Practices
EP 1-1-3 Deviations to IPE Engineering Practices EP 3-1-1 S&L P Philosophy
EP 4-1-1 Design Criteria and Loads for Structures
EP 4-2-9 Grouting and Base Plates for Structural Steel and Equipment EP 8-4-1 Cooling Towers
EP 9-1-1 Atmospheric Storage Tanks EP 10-3-1 Shop Painting
EP 10-3-8 Galvanized Coatings
ASTM
A123 Zinc (Hot Dip Galvanized) Coatings on Iron and Steel Products
IBCO
Uniform Building Code
OSHA Standards
Subpart D Walking - Working Surfaces
1910.23 Guarding Floor, Wall Openings and Holes 1910.24 Fixed Industrial Stairs
1910.27 Fixed Ladders

DEFINITIONS

GENERAL DESIGN

PLATFORMS

STAIRWAYS AND LADDERS

6.6.6 If a permanent ladder is specified for access from the roof to the internal floating cover, it shall be designed to accommodate the full travel of the floating cover.

6.7 Additional ladder design requirements shall be per Table 1.Table 1

ACCESS WALKWAYS

CROSSOVERS FOR EARTHEN DIKES

8.2 Steel and Concrete Crossovers

The design of steel and concrete crossovers shall be in accordance with Table 2.

PERMANENT HANDLING FACILITIES

FABRICATION DETAILS

11.0 TABLES

TABLE 1

ACCESS PROVISIONS FOR EQUIPMENT

ACCESS PROVIDED EQUIPMENT ITEM
Permanent Ladder Check valves--all sizes (at vessels)
Gate and Globe valves-NPS 3 and smaller (at vessels) Gauge glasses and trycocks
Handholes
Instruments Take-off valves Temperature instruments on vessels
Level controls between 7 feet and 12 feet above grade
Furnace observation doors between 7 feet and 12 feet above grade
Permanent Platform Machinery mounted on elevated platforms
Heat exchanger cover, channels, or bonnet flanges (1) Manholes, service and inspection openings (1) Process blinds (1)
Relief valves (vertical vessels) all sizes Relief valves (horizontal vessels) all sizes Clean out points
Furnace soot blowers
Furnace burners when inaccessible from grade Furnace observation doors (1)
Furnace sample ports (1)
Emergency isolation (block) valves (EBv)
Groups of valves at battery limits in elevated pipe racks Gate and Globe valves-NPS 4 and larger (at vessels) Motor operated valves
Instrumentation and Controls which require operator attention Control valves--all sizes
Level controllers (1)
Sampling devices on vessels (1)
Mobile Stair All servicing between 7 feet and 12 feet above grade except as noted herein

TABLE 1

ACCESS PROVISIONS FOR EQUIPMENT (CONTINUED)

ACCESS PROVIDED ITEM OF EQUIPMENT
No permanent access Nozzles on vessels (2)
Block valves in yard banks
Metal temperature measuring points on vessels
Temperature and pressure points in piping for board mounted gages Orifices in lower yard banks
Check valves not at vessels Silencers
Exhaust heads
Temporary
platform supports		 Furnace header boxes containing removable plugs and air coolers

NOTES:

TABLE 2

DIMENSIONS FOR ACCESS WALKWAYS, PLATFORMS, LADDERS, AND MAINTENANCE MINIMUM DIMENSIONS, EXCEPT AS OTHERWISE NOTED

ITEM DIMENSION DESCRIPTIONS DIMENSIONS
Accessways Headroom height over stairs, platforms, walkways, passageways, and working areas. Headroom is measured to the lowest point of overhead structural framing (including fireproofing), piping (including
insulation), and equipment.		 7'-6"
Access
Walkways		 Headroom height for projections over platforms, walkways,
passageways, and working areas		 7'-0"
Width of stairways (back to back of stringers) 2'-6"
Width of landings (in direction of stairways) 3'-0"
Width of walkways (at grade or elevated) 2'-6"
Width of elevated walkways receiving traffic from two or more routes 4'-0"
Maximum vertical rise of stairways (one flight) 15'-0"
Maximum horizontal distance from any point on platform
to an emergency escape		 75'-0"
Maximum length of dead-end platforms in escape routes (1) 20'-0"
Platforms
(1)		 Maximum variance in platform elevations without intermediate step 9"
Minimum clearance width of platforms (6) 2'-6"
Width of manhole platforms on vertical vessels shall be the greater of width between inside radius and inside of platform
on vertical vessels (10")		 3'-0" or one manhole
diameter + 12"
Ladders
(2), (3), (4), (6)		 Maximum vertical rise of operational ladders (single run) 30'-0"
Maximum allowable slope of ladders from vertical 15
Toe clearance from centerline of rung to obstruction 8"
Clear climbing space for 90° pitch ladders (3) 2'-6"
Width of ladders 1'-6"
Clear climbing space for 75° pitch ladders (3) 3'-0"
Operation and
Maintenance		 Access to equipment, valves, instruments, and manholes
located within 7 ft. to 12 ft. above grade		 (5)

NOTES:

might select an escape path which would lead to such a dead end. The dead end shall be specified by the Owner's Engineer.

TABLE 3 FABRICATION DETAIL REFERENCES

ITEM FIGURES
vessel Platform 3A, 3B, 3C
Platform Arrangement for vertical vessels 4
Pipe Opening Floor Cover 5
Platforms at the Top of vessels 6
Platforms at Elevated Heat Exchangers 7
Ladder and Cage Arrangement 8A, 8B, 8C, 8D
Ladder Support from Shell of vertical vessel 9
Ladder Support Details for vertical vessels 10
Ladder and Cage details 11A, 11B, 11C, 11D
Ladder Safety Gate 12
Typical Handrail Detail 13A, 13B
Typical Handrail, Floorplate and Grating Connections 14A, 14B
Floor Grating Arrangement in Structures 15A, 15B, 15C
Stair Details - Grade to Platform 16
Stair Details - Platform to Platform 17
Stair Stringer Details 18
Stair Tread Detail 19
Wooden Crossover 20A, 20B
Concrete Crossover 21
Steel Crossover 22A, 22B
Tank Ladders and Railing 23, 24, 25

TABLE 4 DOCUMENTATION REQUIREMENTS FOR AUXILIARY STRUCTURES FOR OPERATION AND MAINTENANCE PER EP 4-5-3

Item Description Format As-Built
1 Fabrication drawings in accordance with paragraph 10.1. See EP 2-5-2 Yes
2 Details for auxiliary structures not covered in Table
3 of this Practice.		 See EP 2-5-2 Yes

12.0 FIGURES

FIGURE 1

TOWER AREAS OF DIVISION

Figure

NOTES:

(1) Platform operating and maintenance area shall face crane access area.

FIGURE 2

TYPICAL TOWER PLATFORM AND LADDER ELEVATIONS

Figure

FIGURE 3A

VESSEL PLATFORM - PLAN VIEW

Figure

NOTES:

(1) See Figure 3C for sections.

FIGURE 3B

VESSEL PLATFORM - TYPICAL SECTIONS

Figure

NOTES:

(2) See Figure 3C for details.

FIGURE 3C

VESSEL PLATFORM - SECTION AND DETAILS

Figure

NOTES:

FIGURE 3D

VESSEL PLATFORM - TYPICAL SECTION WITH GRATING

Figure

NOTES:

FIGURE 4A

PLATFORM ARRANGEMENTS FOR VERTICAL VESSELS

Figure

FIGURE 4B

OTHER ACCEPTABLE VESSEL PLATFORM ARRANGEMENTS - PLAN VIEW

Figure

NOTES:

(1) See also Notes on Figure 4A.

FIGURE 5

PIPE OPENING FLOOR COVER

Figure

FIGURE 6

PLATFORMS AT THE TOP OF VESSELS

Figure

FIGURE 7

PLATFORMS AT ELEVATED HEAT EXCHANGERS

Figure

NOTES:

FIGURE 8A

LADDER AND CAGE ARRANGEMENT

Figure

FIGURE 8B

LADDER AND CAGE ARRANGEMENT - SECTIONS

Figure

FIGURE 8C

LADDER AND CAGE ARRANGEMENT - DETAILS A AND B

Figure

FIGURE 8D

LADDER AND CAGE ARRANGEMENT

TYPICAL LADDER CONNECTION TO STRUCTURE DETAILS

Figure

FIGURE 9

LADDER SUPPORTED FROM SHELL OF VERTICAL VESSEL

Figure

FIGURE 10

LADDER SUPPORT DETAILS FOR VERTICAL VESSELS

Figure

NOTES:

FIGURE 11A

LADDER AND CAGE DETAILS – ELEVATION

Figure

FIGURE 11B

LADDER AND CAGE DETAILS - PLAN VIEW

Figure

FIGURE 11C

LADDER AND CAGE DETAILS – SECTIONS

Figure

FIGURE 11D

LADDER AND CAGE DETAILS - FOOTING OR BASE DETAIL

Figure

NOTES:

FIGURE 12 LADDER SAFETY GATE

Figure

NOTES:

FIGURE 13A TYPICAL HANDRAIL DETAIL

Figure

NOTES:

FIGURE 13B

REMOVABLE HANDRAIL SECTION DETAIL

Figure

NOTES:

FIGURE 14A

TYPICAL HANDRAIL, FLOOR PLATE AND GRATING CONNECTIONS

Figure

FIGURE 14B

TYPICAL HANDRAIL, FLOOR PLATE AND GRATING CONNECTIONS - CONTINUED

Figure

NOTES:

FIGURE 15A

FLOOR GRATING ARRANGEMENT IN STRUCTURES - PLAN VIEW

Figure

NOTES:

FIGURE 15B

FLOOR GRATING ARRANGEMENT IN STRUCTURES - SECTIONS

Figure

FIGURE 15C

FLOOR GRATING ARRANGEMENT IN STRUCTURES

- CUTOUT REINFORCEMENT

Figure

NOTE:

(1) Reinforcement is required for all 10-in. diameter and larger holes cut in grating.

FIGURE 16

STAIR DETAILS - GRADE TO PLATFORM

Figure

NOTE:

(1) All handrail, midrail and handrail posts shall be angle 2 1/2 x 2 1/2 x 1/4 in.

FIGURE 17

STAIR DETAILS - PLATFORM TO PLATFORM

Figure

NOTE:

(1) All handrail, midrail and handrail posts shall be angle 2 1/2 x 2 1/2 x 1/4 in.

FIGURE 18

STAIR STRINGER DETAILS

Figure

FIGURE 19 STAIR TREAD DETAIL

Figure

NOTES:

FIGURE 20A

WOODEN CROSSOVER – ELEVATION

Figure

FIGURE 20B

WOODEN CROSSOVER - DETAIL AND SECTIONS

Figure

Figure

Figure

FIGURE 21 CONCRETE FIGURE

Figure

FIGURE 22A

STEEL CROSSOVER - ELEVATION

Figure

Table 1 - Dimensions Table 1 - Dimensions Table 1 - Dimensions Table 1 - Dimensions Table 1 - Dimensions
Dike Height H1 Or H2 # Of Risers At 8 In. T1 Or T2 # Of Treads At 9 In.
0 Ft. To 3 Ft.-6 In. 4 Ft. 6 3 Ft.-9 In. 5
3 Ft.-6 In. To 4 Ft.-2 In. 4 Ft.-8 In. 7 4 Ft.-6 In. 6
4 Ft.-2 In. To 4 Ft.-10 In. 5 Ft.-4 In. 8 5 Ft.-3 In. 7
4 Ft.-10 In. To 5 Ft.-6 In. 6 Ft. 9 6 Ft. 8
5 Ft.-6 In. To 6 Ft.-2 In. 6 Ft.-8 In. 10 6 Ft.-9 In. 9
6 Ft.-2 In. To 6 Ft.-10 In. 7 Ft.-4 In. 11 7 Ft.-6 In. 10
6 Ft.-10 In. To 7 Ft.-6 In. 8 Ft. 12 8 Ft.-3 In. 11
Table 2 - Dimensions Table 2 - Dimensions
L Stringer Size
0 Ft. To 17 Ft. C8 x 11.5
17 Ft. To 20 Ft. C9 x 13.4
20 Ft. To 23 Ft. C10 x 15.3
23 Ft. To 28 Ft. C12 x 20.7

FIGURE 22B

STEEL CROSSOVER - PLAN AND DETAILSTANK LADDER FIGURE

Figure

FIGURE 23

TANK LADDER DETAILS

Figure

NOTES:

FIGURE 24

RAILING AT FOAM CHAMBERS FOR FIXED ROOF FIGURE

Figure

NOTES:

FIGURE 25

WING RAILING FOR FIXED ROOF FIGURE

Figure

NOTES:

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