1. For changes in vertical and horizontal alignment, pre-fabricated cold field bends are provided.
2. Over bends are made in manner that centre of bend bears the highest point of trench bottom.
3. Sag bends shall fit the bottom of the trench.
4. Side bends shall have specified clearance to the outside wall of the trench.
5. The radius of cold field bends shall not be more than 40 times the dia of the pipe (for 18” and above) and 30 times the dia of pie (for 18” below).
6. Pipes with longitudinal welds are bent a way that weld lies in the plane passing through the neutral axis of bend.