| 摘要 |
<p>An open throat power tong (10) as commonly used for making up and/or breaking apart an oilfield tubular connection, comprising a tong body (20), a tong door assembly (40), a partial ring member (30) and a ring segment (150). The partial ring member (30) and ring segment (150) may not be structurally connected and each may support one or more jaw members thereon for gripping a tubular (11). The partial ring member (30) and ring segment (150) may rotate substantially in unison along a substantially common plane and about a common axis, along a defined rotation course through the tong body (20) and door (40). The ring segment (150) may be substantially secured within the door when the door (40) is opened. An improved latch mechanism (100) is included for securing the door (40) to the tong body (20) to facilitate relatively easy closing and latching and unlatching of the door (40) with the tong body (20), ant to prevent expansion of the open throat (25) during application of high torque.</p> |
