650-776 Insert Plate Weld Spacing Terminology Rev. 0 (Spring 2013)

Agenda Item: 650-776
Title: /

Insert Plate Weld Spacing Terminology

Date: / 04/23/2013
Contact: / Name: / John A Pachuta
Company: / Sunoco Logistics L.P.
Phone: / 610-670-3269
E-mail: /
Purpose:
Reference: / To make “insert”/”thickened insert” terminology consistent
Figure 5-6 and Section 5.7.3 in API Standard 650
Source: / D. Rosenkrantz e-mail 09/05/12
Revision: / 0
Impact: / None
Background: / There are basically three types of shell penetration connections – regular type reinforced opening (RTR), low type reinforced opening (LTR), and non-reinforced opening (SN). Section 5.7.3 and Figure 5-6 of API Standard 650 defines the minimum weld spacing requirements between shell penetration connections and adjacent shell plate joints, and between each other.
Proposal: / Revise some of the wording in paragraphs 5.7.3.1, 5.7.3.2, and 5.7.3.3 in API Standard 650, and in the following areas of Figure 5-6, in API Standard 650: Note on RTR, Note on LTR, and Note 2 on bottom of page.
Rationale: / The new proposed wording will communicate more clearly, the intent of Section 5.7.3 and Figure 5-6 in API Standard 650.
Notes:

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650-776 Insert Plate Weld Spacing Terminology Rev. 0 (Spring 2013)

Existing Wording -

5.7.3.1 For non-stress-relieved welds on shell plates over 13 mm (½ in.) thick, the minimum spacing between penetration connections and adjacent shell plate joints shall be governed by the following:

a. The outer edge or toe of fillet around a penetration, around the periphery of a thickened insert plate, or around the periphery of a reinforcing plate shall be spaced at least the greater of eight times the weld size or 250 mm (10 in.)(dimension A or B in Figure 5-6) from the centerline of any butt-welded shell joints.

b. The welds around the periphery of a thickened insert plate, around a reinforcing insert plate, or around a reinforcing plate shall be spaced at least the greater of eight times the larger weld size or 150 mm (6 in.)(dimension E in Figure 5-6) from each other.

5.7.3.2 Where stress-relieving of the periphery weld has been performed prior to welding of the adjacent shell joint or where a non-stress-relieved weld is on a shell plate less than or equal to 13 mm (½ in.) thick, the spacing may be reduced to 150 mm (6 in.)(dimension A in Fig. 5-6) from vertical joints or to the greater of 75 mm (3 in.) or 2½ times the shell thickness (dimension B in Fig. 5-6) from horizontal joints. The spacing between the welds around the periphery of a thickened insert plate or around a reinforcing plate shall be the greater of 75 mm (3 in.) or 2½ times the shell thickness (dimension E in Figure 5-6).

5.7.3.3 The rules in 5.7.3.1 and 5.7.3.2 shall also apply to the bottom-to-shell joint (dimension C in Figure 5-6) unless, as an alternative, the insert plate or reinforcing plate extends to the bottom-to-shell joint and intersects it at approximately 90 degrees (dimension D in Figure 5-6). A minimum distance of 75 mm (3 in.) shall be maintained between the toe of a weld around a non-reinforced penetration (see 5.7.2.1) and the toe of the shell-to-bottom weld.

Proposed New Wording –

a. The toe of the fillet weld around a non-reinforced penetration or around the periphery of a reinforcing plate, and the outer edge of a butt-weld around the periphery of a thickened insert plate or insert plate with a reinforced penetration, shall be spaced at least the greater of eight times the weld size or 250 mm (10 in.) from the centerline of any butt-welded shell joints, as illustrated in Figure 5-6, dimensions A or B.

b. The welds around the periphery of a thickened insert plate, around the periphery of an insert plate with a reinforced penetration, around a non-reinforced penetration, or around a reinforcing plate shall be spaced at least the greater of eight times the larger weld size or 150 mm (6 in.) from each other, as illustrated in Figure 5-6, dimension E.

5.7.3.2 Where stress-relieving of the periphery weld has been performed prior to welding of the adjacent shell joint or where a non-stress-relieved weld is on a shell plate which is less than or equal to 13 mm (½ in.) thick, the minimum weld spacing may be reduced to 150 mm (6 in.) from vertical joints, as illustrated in Figure 5-6, dimension A or to the greater of 75 mm (3 in.) or 2½ times the shell thickness from horizontal joints, as illustrated in Figure 5-6, dimension B. The spacing between the welds around the periphery of a thickened insert plate, around the periphery of an insert plate with a reinforced penetration, or around a reinforcing plate, or around a non-reinforced penetration, shall be the greater of 75 mm (3 in.) or 2½ times the shell thickness, as illustrated in Figure 5-6, dimension E.

5.7.3.3 The rules in 5.7.3.1 and 5.7.3.2 shall also apply to the bottom-to-shell joint (dimension C in Figure 5-6) unless, as an alternative, the thickened insert plate, insert plate with a reinforced penetration, or reinforcing plate extends to the bottom-to-shell joint and intersects it at approximately 90 degrees, as illustrated in Figure 5-6, dimension D. A minimum distance of 75 mm (3 in.) shall be maintained between the toe of a weld around a non-reinforced penetration (see 5.7.2.1) and the toe of the shell-to-bottom weld.

Existing Wording -

Figure 5-6 Minimum Weld Requirements for Openings in Shells According to 5.7.3

Note:

RTR = Regular-Type Reinforced Opening (nozzle or manhole) with diamond or circular shape reinforcing plate or insert plate that does not extend to the bottom (see Figure 5-7A and Figure 5-8).

LTR = Low-Type Reinforced Opening (nozzle or manhole) using tombstone type reinforcing plate or insert plate that extends to the bottom [see Figure 5-8, Detail (a) and Detail (b)].

Notes:

2. t = shell nominal thickness. 8W = 8 times the largest weld size for reinforcing plate or insert plate periphery weld (fillet or butt weld) from the toe of the periphery weld to the centerline of the shell butt-weld.

Proposed New Wording –

Figure 5-6 Minimum Weld Requirements for Openings in Shells According to 5.7.3

Note:

RTR = Regular-Type Reinforced Opening (nozzle or manhole) with diamond or circular shape reinforcing plate, or insert plate with a reinforced penetration, or thickened insert plate, that does not extend to the bottom (see Figure 5-7A and Figure 5-8).

LTR = Low-Type Reinforced Opening (nozzle or manhole) using tombstone type reinforcing plate or thickened insert plate that extends to the bottom [see Figure 5-8, Detail (a) and Detail (b)].

Notes:

2. t = shell nominal thickness. 8W = 8 times the largest weld size for reinforcing plate or thickened insert plate periphery weld (fillet or butt weld) from the toe of the periphery weld to the centerline of the shell butt-weld.

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