Forged DN125A - 250A Weld Neck Pipe Flanges Galvanizing For Oil Pipe Connection

Forged DN125A - 250A Weld Neck Pipe Flanges Galvanizing For Oil Pipe Connection Size2'-24'

1.Carbon Steel

Carbon Steel :A105,CT20,CT25,P245GH Low Temperature

Carbon Steel: ASTM SA350 LF2

High Strength Steel: ASTM SA694 F42/46/52/56/60/65/70

AISI classification

Carbon steel is broken down into four classes based on carbon content:

Low-carbon steel

0.05 to 0.30% carbon (plain carbon steel) content.

Medium-carbon steel

Approximately 0.3–0.6% carbon content.Balances ductility and strength and has good wear

resistance; used for large parts, forging and automotive components.

High-carbon steel

Approximately 0.60 to 1.00% carbon content.Very strong, used for springs, edged tools, and high-

strength wires.

2.ASTM B 16.5

The B16.5 Standard defines the following:

(1) Dimensions

(2) Tolerances

(3) Materials

(4) Markings

(5) Pressure/Temperature Ratings

(6) Pressure Testing

3.Product catalogue

4.Product display

5.ASME standards (U.S.)

Pipe flanges that are made to standards called out by ASME B16.5 or ASME B16.47, and MSS SP-44.

They are typically made from forged materials and have machined surfaces. ASME B16.5 refers to

nominal pipe sizes (NPS) from ½" to 24". B16.47 covers NPSs from 26" to 60". Each specification

further delineates flanges into pressure classes: 150, 300, 400, 600, 900, 1500 and 2500 for B16.5,

and B16.47 delineates its flanges into pressure classes 75, 150, 300, 400, 600, 900. However these

classes do not correspond to maximum pressures in psi. Instead, the maximum pressure depends on

the material of the flange and the temperature. For example, the maximum pressure for a Class 150

flange is 285 psi, and for a Class 300 Flange it is 740 psi (both are for ASTM A105 Carbon Steel and

temperatures below 100F).

The gasket type and bolt type are generally specified by the standard(s); however, sometimes the

standards refer to the ASME Boiler and Pressure Vessel Code (B&PVC) for details (see ASME Code

Section VIII Division 1 – Appendix 2). These flanges are recognized by ASME Pipe Codes such as

ASME B31.1 Power Piping, and ASME B31.3 Process Piping.

Materials for flanges are usually under ASME designation: SA-105 (Specification for Carbon Steel

Forgings for Piping Applications), SA-266 (Specification for Carbon Steel Forgings for Pressure Vessel

Components), or SA-182 (Specification for Forged or Rolled Alloy-Steel Pipe Flanges, Forged Fittings,

and Valves and Parts for High-Temperature Service). In addition, there are many "industry standard"

flanges that in some circumstance may be used on ASME work.

The product range includes SORF, SOFF, BLRF, BLFF, WNRF (XS, XXS, STD & Schedule 20, 40, 80),

WNFF (XS, XXS, STD & Schedule 20, 40, 80), SWRF (XS & STD), SWFF (XS & STD), Threaded RF,

Threaded FF & LJ, with sizes from 1/2" to 16". The bolting material used for flange connection is stud

bolts mated with two nut (washer when required). In Petrochemical industries, ASTM A193 B7 STUD

& ASTM A193 B16 Stud Bolts are used as these have high tensile strength.

6.Galvanizing

Galvanizing protects the underlying iron or steel in the following main ways:

The zinc coating, when intact, prevents corrosive substances from reaching the underlying steel or iron.

The zinc protects iron by corroding first. For better results, application of chromates over zinc is also

seen as an industrial trend.

In the event the underlying metal becomes exposed, protection can continue as long as there is zinc

close enough to be electrically coupled. After all of the zinc in the immediate area is consumed,

localized corrosion of the base metal can occur.