From: Michael E. Viola
Sent: Tuesday, December 04, 2007 12:35 PM
To: Michael E. Viola; Thomas G. Brown; Robert A. Ellis; Phil
Heitzenroeder; Lawrence E. Dudek; Kristopher R. Gilton; Erik D. Perry;
Robert F. Parsells
Subject: UPDATE: Below the hook lifting devices BTH-1 rules

Importance: High

Attachments: BTH.pdf

The new version of ASME B30.20-2006 has changed their language to reference BTH-1. See 
the quoted information below my signature. My original guidance applies:
BTH-1 para 3-1.3a states
(a) Design factors for Design Category A lifting devices shall be not less than 2.00 
for limit states of yielding or buckling and 2.40 for limit states of fracture and for 
connection design.

B30.20-2006 -1.2.2(a) Welding. All welding shall be in accordance with
ANSI/AWS D14.1 and ASME BTH-1.

Thanks,
Mike Viola, PPPL, (609) 243 3655
=============================================================
From: Suniga, Joe R 
Mike, What revision of B30.20 are you looking at??  The 2006 revision
does not state that anymore.  Here is what the current version says:

20-1.2.2 Construction
The manufacturer shall verify that structural and
mechanical lifting devices are designed by or under the
direct supervision of a qualified person. The design shall
be in accordance with ASME BTH-1 and shall consider
the stresses resulting from the application of rated load
plus the weight of the lifting device.
Structural and mechanical lifting devices shall be
designed to ASME BTH-1 Design Category B (static
strength criteria) and the proper Service Class (fatigue
life criteria) selected for its number of load cycles, unless
a qualified person representing the owner, purchaser, or
user of the lifting device determines and can demonstrate
that ASME BTH-1 Design Category A is appropriate.
Design Category A shall only be designated when the
magnitude and variation of loads applied to the lifter
are predicable and do not exceed the rated capacity,
where the loading and environmental conditions are
accurately defined, service is not severe, and the anticipated
number of load cycles does not exceed Service
Class 0.
(a) Welding. All welding shall be in accordance with
ANSI/AWS D14.1 and ASME BTH-1.
(b) Guards for Moving Parts. Exposed moving parts,
such as, but not limited to, gearing, projecting shafts,
(06)
ASME B30.20-2006
and chain drives, that constitute a hazard under normal
operating conditions, should be guarded.
(c) Electrical Equipment. External power supply, electrical
equipment, and wiring for below-the-hook lifters
shall comply with ANSI/NFPA 70 and ASME BTH-1.
(d) Modifications. Structural and mechanical lifters
may be modified or rerated, provided such modifications
are analyzed and approved by the equipment manufacturer
or a qualified person. A rerated lifter, or one
whose components have been modified, shall conform
to para. 20-1.2.2 and be tested according to para. 20-1.3.8.
New rated load shall be displayed in accordance with
para. 20-1.2.1.
==============================================================
-----Original Message-----
From: Michael E. Viola 
Sent: Tuesday, December 04, 2007 10:12 AM
To: Thomas G. Brown; Robert A. Ellis; Phil Heitzenroeder; Lawrence E. Dudek; Kristopher R. Gilton
Cc: Erik D. Perry
Subject: Below the hook lifting devices ASME B30.20 vs. BTH-1

Gents,
We must design below the hook lifting devices including plates and spreaders with a design
factor of 3:1 based on YIELD.

Kris Gilton has brought to my attention that ASME B30.20 below the hook lifting devices
which is referenced by BTH-1 as a complimentary document specifically states in 20-1.2.2 
construction:
The load-bearing structural components of a lifter shall be designed to withstand the 
stresses imposed by its rated load plus the weight of the lifter, with minimum design 
factor of three, based on yield strength of the material and with stress ranges that do 
not exceed the values given in ANSI/AWS D14.1 for the applicable condition.  All welding 
shall be in accordance with ANSI/AWS D14.1

I have deemed all of our lifts to be Cat A Class 0 per 2-2.1 of BTH-1 

BTH-1 para 3-1.3a states
(a) Design factors for Design Category A lifting
devices shall be not less than 2.00 for limit states of
yielding or buckling and 2.40 for limit states of fracture
and for connection design.

Therefore we must design below the hook lifting devices including plates and spreaders with a design factor of 3:1 based on yield.  I conferred with Erik Perry and he agrees.

I am investigating further.

Mike