Structural Analysis, Design, and Implementation of Safety …
445
2 Technical Requirement of Structure Fabrication
During the last periodic hydrostatic test of vessels as per SMPV (U) Rule 19,
CCOE has recommended this facility incorporation on the vessels. Conceptual design
approval was taken from CCOE, Nagpur before the work commences. The main
purpose was to build this structure to the access to all four numbers of medium
pressure (MP) vessels by a single ladder. The structure consists of two part (i) spiral
ladder and (ii) joint bridge type platform, which were mechanically connected to the
existing extended platform at top of all vessels with side pipe railing support. The
following are the technical needs and constraints of fabricated structure; fabrication
and installation are summarized.
(i) The spiral ladder will be installed adjacent to center of all vessels by a distance
of 3–4 m as per the CCOE Rule 33 of SMPV (U) Rules, l98l.
(ii) The height of the spiral ladder is to be 13 m from the ground; it should match
with vessels top platform plane.
(iii) No welding to be done on any vessels elements with fabricated structure.
(iv) To support the ladder to prevent and mitigate the cantilever aspects, an existing
cleat of pressure vessels can be used for support welding.
(v) The ladder should be designed to carry maximum of two person load nearly 300
kg and checked for failure due to wind load.
(vi) Restriction of extra support provision of the platform structure on the ground
level as per the CCOE norms in the vessels premises.
3 Design Parameters and Boundary Conditions
for Structure
Figure 3 display the top view of vessels and the bridge type platform which is
supported and welded over the I-Beam with chequred plate along with the angle
beam welded at bottom to prevent bending of platform in width direction. From one
vessel to other vessel, the person can easily go to all the vessels and get down from
the spiral ladder. The design criteria and parameters of each elements of structure
are summarized in Table 1.
4 Fabrication and Installation Procedure
All the elements of the structure are separately fabricated. The foundation plate
was placed at the required spot levelling with the pressure vessels in the reinforced
445
2 Technical Requirement of Structure Fabrication
During the last periodic hydrostatic test of vessels as per SMPV (U) Rule 19,
CCOE has recommended this facility incorporation on the vessels. Conceptual design
approval was taken from CCOE, Nagpur before the work commences. The main
purpose was to build this structure to the access to all four numbers of medium
pressure (MP) vessels by a single ladder. The structure consists of two part (i) spiral
ladder and (ii) joint bridge type platform, which were mechanically connected to the
existing extended platform at top of all vessels with side pipe railing support. The
following are the technical needs and constraints of fabricated structure; fabrication
and installation are summarized.
(i) The spiral ladder will be installed adjacent to center of all vessels by a distance
of 3–4 m as per the CCOE Rule 33 of SMPV (U) Rules, l98l.
(ii) The height of the spiral ladder is to be 13 m from the ground; it should match
with vessels top platform plane.
(iii) No welding to be done on any vessels elements with fabricated structure.
(iv) To support the ladder to prevent and mitigate the cantilever aspects, an existing
cleat of pressure vessels can be used for support welding.
(v) The ladder should be designed to carry maximum of two person load nearly 300
kg and checked for failure due to wind load.
(vi) Restriction of extra support provision of the platform structure on the ground
level as per the CCOE norms in the vessels premises.
3 Design Parameters and Boundary Conditions
for Structure
Figure 3 display the top view of vessels and the bridge type platform which is
supported and welded over the I-Beam with chequred plate along with the angle
beam welded at bottom to prevent bending of platform in width direction. From one
vessel to other vessel, the person can easily go to all the vessels and get down from
the spiral ladder. The design criteria and parameters of each elements of structure
are summarized in Table 1.
4 Fabrication and Installation Procedure
All the elements of the structure are separately fabricated. The foundation plate
was placed at the required spot levelling with the pressure vessels in the reinforced