Horizontal “cow-horn” type bumpers with vertical guide Horizontal force in any direction:
0.10 x W
0.20 x W
0.05 x W
Vertical (friction) force:
0.01 x W
0.02 x W
0.005 x W
Horizontal force in any direction shall be combined with the vertical force to establish the worst
design case.
Vertical “cow-horn” type guide with horizontal bumper Horizontal force in any direction:
0.10 x W
0.20 x W
0.05 x W
Vertical force on inclined guide-face:
0.10 x W
0.20 x W
0.05 x W
Horizontal force in any direction shall be combined with the vertical force to establish the worst
design case.
17.4.2
For inshore lifts under controlled conditions, bumpers and guides may be designed to 50% of the
forces shown in Table 17-1.
17.4.3
Bumpers and guides that are deemed to arrest secondary forces (after the primary bumper and guide
system has arrested the primary impact forces) may be designed to 50% of the forces shown in Table
17-1.
17.4.4
Lower bumper and guide forces may be agreed with the MWS for decommissioning structures when
local damage may be acceptable.
17.5 DESIGN CONSIDERATIONS 17.5.1
The connection into the module, and the members framing the bumper or guide location, should be at
least as strong as the bumper or guide.
17.5.2
The stiffness of bumper and guide members should be as low as possible, in order that they may
deflect appreciably without yielding.
17.5.3
Design of bumpers and guides should cater for easy sliding motion of the guide in contact with a
bumper. Sloping members should be at an acute angle to the vertical. Ledges and sharp corners
should be avoided in areas of possible contact, and weld beads should be ground flush.
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