Patent ID: 6945568

Claim:
In a joint structure for coupling a first component ( 21 ) to a second component ( 22 ) of a fluid flow passage by inserting a portion of said second component ( 22 ) into said first component ( 21 ), wherein said second component is formed as a single unit, the improvement wherein: said second component ( 22 ) is provided with an annular flange portion ( 26 ) having a side and an annular edge portion ( 28 ) having a v-shaped cross-section on an end thereof; said side of said annular flange portion ( 26 ) of said second component ( 22 ) abutting an annular end surface of said first component ( 21 ) which is parallel to said side after the second component and first component are coaxially engaged, said side and said annular end surface being welded together to create a first seal; said annular edge portion ( 28 ) of said second component ( 22 ) being brought into abutting contact with a corresponding annular portion of said first component ( 21 ) to form a complete second seal between and around said annular edge portion on said second component and said corresponding annular portion of said first component; whereby coupling of said components ( 21 , 22 ) to each other is accomplished to create a double-seal comprising said first seal and said second seal in the joint structure.