D:\116108259.doc
Agenda Item:650-618
650-XXX
Title:
Clarify Shell Inset Plate Requirements [ Para. 2.2.3 (d), 3.7.1.7, Fig. 3-4B, 6.1.1.2 (d)]
Date:
May 01, 2006
Contact:
Name:
Bhana D. Mistry P.Eng. ( Chief Engineer/Manager of Engineering)
Company : TIW Steel Platework
Phone
: 905 684 9421, Fax 905 684-7310
E-mail
: bmistry@tiwsteelplatework.ca
Purpose:
Clarify RT of Full Shell Height Insert Plate. Expand scope to provide clear definition of insert
plate, increase thickness of CSA G40.21.350 WT/50WT for insert plate and correct details
of insert plate in Fig. 3.4B
Source:
650-I-08/05
Revision:
0. Passed to SCLB on May 01, 2006.
Impact:
The business impact of this item is neutral or some cost saving.
Background: Agenda Item was taken out as a result of 650-I-08/05 to clarify RT of full shell course height
insert plate and was assigned to Rob Annett. I volunteered to assist and decided to
undertake the item and expand the scope to address some other deficiency with regard to
shell insert plate.
The agenda item will address:
(a) Provide proper definition of insert plate, similar to API-653.
Shell insert plates can be circular or can be rectangular with rounded corners. Shell
insert can have reinforcing element for shell penetration in the form of thickened insert plate,
separate reinforcing plate or thickened nozzle neck or combination thereof. Revise 3.7.1.7
(b) Expand thickness of CSA G40.21.350 WT/50WTfor Insert Plates. This will enable
greater use of insert plate on large tanks using CSA Grade steel. We are now
restricted to use A-537-Cl.2 for insert plate with CSA G40.21.300W or 350WT.
Properties of CSA G40.21 350WT/50WT are quite similar to those of A-537-Cl.1. I
have attached properties of CSA G40.21.350WT/50WT and A-537-cl.1 for easy
reference .( Revise 2.2.3 (f))
© Correct Fig. 3-4B for Insert Plate Details
(d) Clarify RT requirements for insert plate, including full shell course height insert
plate. Revise (6.1.2.2 (d))
Page 1 of 8
D:\116108259.doc
Proposal:
2.2.3 CSA Specifications
f.
Grade 350W(50W) is acceptable for plate to a maximum thickness of 45 mm (1.75
in.) [insert plates to a maximum thickness of 50 mm (2 in.) 100 mm (4 in.)] if fully
killed and made to fine-grain practice.
3.7.1.7 Shell openings may be reinforced by the use of an insert plate per Fig. 3-
4 B. Insert plate may have the same thickness as an adjacent shell plate or may
be a thickened to provide reinforcing. Insert plate ,if rectangular, shall be
shaped with rounded corners (except for edges terminating at the tank bottom
or at joints between shell courses) with a radius of not less than greater of 150
mm (6 in) or 6t where t is the thickness of shell course containing the insert
plate. Insert plate may contain multiple shell openings. The thickness and
dimensions of the proposed shape of insert plate shall meet the area of
reinforcing of 3.7.2; and weld spacing requirements outlined in 3.7.3. Periphery
of the thickened insert plates shall have a 1:4 tapered transition to the thickness of the
adjacent shell plates when the insert plate exceeds the adjacent shell thickness by more
than 3 mm (1/8”).
In addition, the following requirements shall be met.
(a) The minimum diameter of a circular thickened insert plate or the side of a
rectangular thickened insert plate shall be at least twice the diameter of the
penetration or the penetration diameter plus 300 mm (12”).
(b) When reinforcing plate is used, the minimum diameter of a circular
insert plate or the side of a rectangular insert plate shall equal the
diameter of reinforcing plate plus 300 mm (12”).
Fig.3.4B:
Correct Fig.3.4B for Insert Type Reinforcement as shown in mark-up.
6.1.2.2
d.The butt-weld around the periphery of an insert plate [not extending full shell
height] containing shell openings [i.e. nozzle, manway, flush type cleanout, flush
type shell connection] and its reinforcing elements, shall be completely
radiographed.
For shell insert plate which extends full shell course height, vertical and
horizontal butt joints as well as T junctions shall be radio-graphed, applying
the same rules as they apply to other adjacent shell plate at the location.
Notes:
Page 2 of 8
D:\116108259.doc
Page 3 of 8
D:\116108259.doc
Page 4 of 8
D:\116108259.doc
Page 5 of 8
D:\116108259.doc
Page 6 of 8
D:\116108259.doc
Page 7 of 8
D:\116108259.doc
Page 8 of 8