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: / Dec.08, 2006Contact: / 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 :
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: /
- Passed to SCLB on May 01,2006.
- Passed for Re-Ballot on Oct.31,06
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. Propertiesof 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))
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 thicker to provide reinforcing.Rectangular insert plate shall have rounded corners (except for edges terminating at the tank bottom or at joints between shell courses) with a radius no less than greater of 150 mm (6 in) or 6t where t is the thickness of the shell course containing the insert plate. Insert plate may contain multiple shell openings. The thickness and dimensions of insert plate shall provide the reinforcing required per 3.7.2. The weld spacing shall meet requirements of 3.7.3. The periphery of insert plates shall have a 1:4 tapered transition to the thickness of the adjacent shell plateswhen the insert plate thickness exceeds the adjacent shell thickness by more than 3 mm (1/8”).
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 that does not extend over a full shell course height and that contains shell openings [i.e. nozzle, manway, flush type cleanout, flush type shell connection] and its reinforcing elements shall be completely radiographed.
The butt-weld around the periphery of an insert plate which extends over a full shell course height, vertical and horizontal butt joints and intersections of vertical and horizontal weld joints shall be radiographed using the same rules that apply to the weld joints in adjacent shell plates in the same shell course.
Notes:
Page 1 of 8