This series of pump has single stage. To reach the needed pressure, the input gas should be pressurized to some degree in advance. The pre-adding pressure is different according to the needed maximum pressure. The maximum pressure can be up to 80Mpa. The reversing way of OMD-Series is the same as that of OMA-Series, but OMD-Series has double pump heads, which is designed based on OMA-Series. The pump is made of aluminum alloy and stainless steel. The diameter of its drive piston is 160mm, drive gas pressure≤8bar. Both pump heads can cool the exhaust gas. The pipelines which connect the two inlets and two outlets will be completed according to customers’ requirements before they leave the factory.