Abstract— Expander machine is used to expand L-SAW and spiral welded pipes. Mechanical expander is used to expand pipes mechanically while hydro tester unit after that is used to hydro test pipes. Now a days technology is changing and people are always wish to save their cost of production, time, space and human power involvement. By combining mechanical expander and hydro tester unit of pipe manufacturing plant, one can easily achieve benefits of both. This paper is based on the combination of two machines of pipe manufacturing to increase the profit. Few pipe manufacturing plant have seen these benefits and have already implemented It  .
Keywords— Expander, Hydro tester, Hydraulic expander, LSAW pipe, Spiral welded pipe.
In pipe manufacturing, there are several steps and machines to convert raw material (plate/coil) to the final product (pipe). Mechanical expander and hydro tester are two essential machines of it, cost wise as well as need wise. Mechanical expander expands the pipe to require diameter and hydro tester test it for any welding defect or leakage. Millions of rupees are involved in the construction of these two machines however now a days few companies have implemented the lean production concept and the combination of these two machines can save money and time. Many researchers have already given their thoughts and research work regarding it. One of it described regarding elimination of hydro tester and stated many advantages plus drawbacks of it . One has described regarding tube expansion issues and methods . In one study there is a comparison between mechanical expansion and hydraulic expansion  . By hydraulic expander we can perform expansion as well as hydraulic testing of pipes at the same place which saves material transportation/handling. In this paper I have included detailed study of hydraulic expander with its advantages and drawbacks plus there is a comparison between hydraulic expander and mechanical expander. This paper only includes the concept and conceptual designs. Designs can be made according to the requirement at the site.