Data Sheet for Product

Technical Bulletin

Document No. 155-303P25

TB 248

March 7, 2005

Cast Iron Flange Dimensions For 2-1/2 through 6-inch

Valves

Siemens Industry, Inc.

Description

This Technical Bulletin shows the standard dimensions for ANSI Class 125 and Class

250 flange valves as defined in ANSI standard B16.1. Also shown are the number and

size of bolt holes for each line size. Siemens Building Technologies manufactures its

2-1/2 through 6-inch valves to these standards.

The letters used in the illustrations correspond to dimensions in the accompanying

tables. Figure 1 and Table 1 show the ANSI Class 125 flange dimensions. Figure 2 and

Table 2 show the ANSI Class 250 flange dimensions.

Figure 1. ANSI Class 125 Flange Dimensions.

Table 1. ANSI Class 125 Cast Iron Flanges. Dimensions in Inches.

Flanges

Drilling

Bolting

Nominal

Pipe Size

Flange

Diameter

Flange

Thickness

Diameter

of Bolt

Circle

Diameter

of Bolt

Holes

Number

of Bolts

Diameter

of Bolts

Length of

Machine

Bolts

2-1/2 7 11/16 5-1/2 3/4 4 5/8 2-1/2

3 7-1/12 3/4 6 3/4 4 5/8 2-1/2

4 9 15/16 7-1/2 3/4 8 5/8 3

5 10 15/16 8-1/2 7/8 8 3/4 3

6 11 1 9-1/2 7/8 8 3/4 3-1/4

Length of Machine Bolt.

PAGE 1
Technical Bulletin Document No. 155-303P25 TB 248 March 7, 2005 Cast Iron Flange Dimensions For 2-1/2 through 6-inch Valves Description This Technical Bulletin shows the standard dimensions for ANSI Class 125 and Class 250 flange valves as defined in ANSI standard B16.1. Also shown are the number and size of bolt holes for each line size. Siemens Building Technologies manufactures its 2-1/2 through 6-inch valves to these standards.
PAGE 2
Technical Instructions Document Number 155-303P25 March 7, 2005 Cast Iron Flange Dimensions for 2-1/2 through 6-inch Valves Dimensions Length of Machine Bolt. Figure 2. ANSI Class 250 Flange Dimensions. Table 2. ANSI Class 250 Cast Iron Flanges. Dimensions in Inches.