These introduction pages will give a

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1 HGG s Profiling Shapes Welcome to the world of Profiling Shapes. HGG s shapes have several distinct advantages as minimum grinding, easy fitting and optimised weld preparation for rapid welding and strong connections. Achieved by accurate machines and advanced software. All profiling shapes have their own specific features depending on member intersection, loads, weld requirements, cutting machine and application specific characteristics. Depending on application are the shapes in accordance with AWS, API and ASME standards. These introduction pages will give a quick overview of the different types of shapes and explain frequently used terminology. Please contact HGG for more information about shapes and our in-house custom shape development for many different applications. info@hgg-group.com End Shapes Intermediate Shapes

2 Terminology Branch member Sprouted profile, mostly with an end profiling shape (or none). Main member Stem profile, mostly with an intermediate profiling shape (or none). Also called run member. Transition zone Zone in which one of the two welded faces of a connection will smoothly changes to fit to another face, to ensure an optimal weld preparation. In particular when the dihedral angle becomes too small or too large along the joint root. Please see next page for more details. Joint root That portion of a walls end along the joint where the members approach closest to each other. In cross section, the joint root may be either a point (fit line) or a line (root face). Root face The cut face on a walls end along the joint root, parallel to the other connecting face after fitting. A technique to decrease weld volume and/or to create a mold for perfect fitting. Root opening (R) The separation at the joint root between the members after fitting. Technique to increase the joint penetration for stronger connections. Shrinkage (S) A length compensation of the member to correct shrinkage of the weld. Slope Angle between main member and branch member. Joint root Weld volume Root face Joint details (section view) Max bevel angle β Bevel angle limit R 45 Plasma 70 Max bevel angle β S Oxyfuel Branch member Slope Dihedral angle ψ Angle between the connected outer faces of the members along the fit line. Essential to make calculations for optimal weld preparation. Please see next page for more details. Bevel angle β The angle formed between a centre line perpendicular to the wall and the cut face of the wall. Equal to burn angle and can be negative or positive. Weld preparation angle φ Angle between the to be welded faces of the members along the joint. Can be an inside or outside weld preparation angle. Also called Joint included angle. A groove angle for example, is a type of weld preparation. Main member Connection overview A perpendicular cut has no bevel; Largest bevel oxyfuel 70 (- or +); Largest bevel plasma 45 (- or +).

3 Weld types and application The angle between the member walls along the joint root changes constantly (see picture below for a simplified view). This dihedral angle is greatest in the toe zone and smallest in the heel zone. On some joints, this dihedral angle differs considerably. In order to maintain a strong connection along the joint in these situations with a minimum of weld volume, it may be necessary to use a combination of weld types. For example a fillet weld in the heel zone because of the small dihedral angle and a groove weld in the toe zone because of the large dihedral angle. Somewhere between these weld types along the joint root, is a zone where the transition starts and ends. This zone is called the transition zone. Weld between the outer walls Weld between an outer wall and a wall end Butt Weld Transition zone ψ Weld between wall ends Overview of used weld types for wall joints. ψ Simplified view of used weld types to connect the walls to each other from toe to heel zone.

4 Optimised weld preparation A few practical examples of how HGG s profiling shapes achieve strong and easy to cut connections with a minimum of weld volume. Also an explanation of the benefits of weld type transition between the toe and heel zones for connections with a small dihedral angle. Please refer to the heel zone with 30 slope for an example. Slope ± 90 with groove weld with similar groove weld Slope ± 60 Weld volume Low Low Low Joint strength High High High Cut difficulty Medium Medium Simple Weld & fit difficulty Medium Medium Simple Weld volume Low High High Joint strength High High Weak Cut difficulty Medium Complicated Complicated Weld & fit difficulty Medium Medium Medium Slope ± 30 Weld volume Joint strength Cut difficulty Weld & fit difficulty Low Medium Medium Medium Heel groove reduction off/on*. Example Saddle and Chamfer. after transition to fillet weld Weld volume Medium Low Low Joint strength Weak Medium Medium Cut difficulty Simple Simple (1 cut) Complicated (2 cuts) Weld & fit difficulty Easy Easy Medium Example PJP Saddle and PJP Chamfer Example Offshore Saddle and Offshore Chamfer ** *Heel groove reduction by 0,5ψ: Reference: Structural Welding Code AWS D1.1/D1.1M:2010; page 72, Table 3.6. **Reference: Structural Welding Code AWS D1.1/D1.1M:2010; page , Figure 3.8, 3.9 & 3.10

5 PJP Saddle A plasma optimised shape for angled pipe to pipe connections and rapid cutting. Design Freedom Adjustable slope. Adjustable eccentricity (E). Predefined start and end point of transition zone by dihedral angle (ψ). (95-70 ) Toe and side zones: adjustable outside weld preparation angle (φ). For highly dynamic connections that are not required to conform to the AWS. Weld Preparation Adjustable root opening. Toe and side zones: constant weld preparation angle (φ) along the joint root. Easy fitting: no need for spacers to create the root opening and the slope. The large heel zone will fixate the correct position. A E (slope 30) Angular Eccentric B C D Transition Multiple

6 Mitre Saddle & Mitre Hole combination To make T-shaped pipe to pipe connections for low pressure piping. Design Freedom Adjustable slope. Adjustable outside weld preparation angle (φ). Weld Preparation Mitre Saddle: shrinkage compensation. Adjustable root opening. Constant weld preparation angle (φ) along joint root as long as the maximum bevel angle is not reached. For high pressure piping and specific weld preparation please see Strainer Hole & Saddle. Perpendicular A C Angular r=d/20 B

7 Strainer Saddle & Strainer Hole combination A pipe to pipe connection for piping with optimised weld preparation for large diameters and thick walls. Design Freedom Adjustable Slope. Adjustable eccentricity (E). Adjustable outside and Strainer inside cut groove details angles (φ). Weld Preparation Shrinkage compensation (S). Adjustable root opening (R). Add a root face to decrease weld volume. Constant weld preparation angle (φ) along the joint root. Perpendicular Angular Eccentric