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Pressure Piping Construction

Every qualified welder will stamp his symbol on work completed by him in the following manner. The mark will be placed at one-meter intervals along the joints and seams of each separate weld. No job is insulated or covered until it is inspected and the stamping is readily visible.

Outweld Industries Inc. can produce 3500 WDIF inches per week.

OutWeld Industries Inc. can produce 15,000 KG structural per week.

The following piping is considered pressure piping and subject to all regulatory requirements.

• Steam piping of any pressure or size.

• Water piping that carries water of more than 66° C (150° F).

• Piping that carries gases such as propane, anhydrous ammonia, or refrigerants.

• Air piping that is 2.5 cm larger than nominal pipe size.

• Oil piping that is 2.5 cm larger than nominal pipe size that carries oil more than 66°C .

• Pipe headers and other piping that is used in direct connection with oil field vessels.

• Any piping used as part of a pressure piping, pressure vessel, or boiler installation and classified by the chief inspector as pressure piping .

Welding Pressure Piping

Welding of pressure piping conforms to the regulations and the satisfaction of the inspector. Welders hold a valid certificate for the procedure performed. The procedure will be one that is duly established and registered.


• All pressure piping equal to or larger than 7.6 cm is welded with the electric arc process

• When pressure piping is made of steel lighter than Schedule 40, the welded fabrication will use no thread joints and will have a working pressure greater than or equal to 690kPa (100 p.s.i.g.) used to calculate the required thickness of the Code formula.

• No threaded joints are used for welded fabrication of steel piping used for water having a temperature of 104° C (220° F) or more than 600 kPa or steam above 1380 kPa (200 p.s.i.g.) Threaded joints are sometimes used with Schedule 40 pipes for steam up to 1380 kPa.

• Seal welding approved by the inspector may be used in threaded joints but is not considered as contributing to the joint's strength.

Many more regulations must be met. Our pressure piping construction is done by certified personnel who adhere to all rules.