| 摘要 |
Sand is filtered from an oil flow from a sand-containing oil producing formation or interval of an oil well by passing the oil flow with entrained sand through a filter assembly containing filtering media in the form of a body of juxtaposed composite particles. Each composite particle has an iron-containing core surrounded by a continuous chromium cladding, the composite particles having a size to permit passage of the oil flow through the body of the composite particles while substantially preventing flow of sand therethrough. |
