API TR 10TR4 pdf download Selection of Centralizers for Primary Cementing Operations 3.2 Advantages and Limitations of Centralizer Types 3.2.1 Bow-spring 1 . This centralizer type has the ability (flexibility) of adjusting to varying hole sizes (can potentially maintain standoff even in irregular size holes). 2. Certain designs incorporate fins to induce swirl (turbulence). 3. Because of the spring bows,...