Positive Displacement Motors
A positive displacement motor (PDM) is a hydraulically driven downhole
motor that uses the Moineau principle to rotate the bit, independent of drill
string rotation. The PDM is made up of several sections:
• By-pass valve or dump sub.
• Motor section.
• Universal joint or connecting rod section.
• Bearing section with drive sub.
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A positive displacement motor (PDM) is a hydraulically driven downhole
motor that uses the Moineau principle to rotate the bit, independent of drill
string rotation. The PDM is made up of several sections:
• By-pass valve or dump sub.
• Motor section.
• Universal joint or connecting rod section.
• Bearing section with drive sub.
