Research on design and pressure-retaining performance of the pressure-retaining sampler for full-ocean-depth sediment

A new type of pressure-retaining sampler (PRS) suitable for full-ocean-depth (11,000 m) sediment sampling is proposed. In order to optimise the pressure-compensation device (PCD) of the PRS, the pressure-compensation model (PCM) is established. This model is adopted to study the influence of different factors on the pressure-retaining performance (PRP) of PRS. The results showed the wall thickness of the PCD had little influence on the PRP, but the pre-charging pressure, ambient temperature difference and working volume had great influence on it, among which the pre-charging pressure had the most obvious influence. Then, a test was carried out. Under different pre-charging pressure, the trend of test pressure-retaining rates were consistent with that of theoretical values, and the error between theoretical and test values were within 5%, which validated PCM. The established PCM can provide theoretical basis for the design of PCD, and the designed PRS can provide new guidance for the design of PRSs.