An object of the present invention is to provide a dry pump and an exhaust gas treatment method which can improve an effect of inhibiting a reaction product from adhering to the inside of a gas outlet port of the dry pump, a gas exhaust pipe, or the like and can also improve an energy saving effect. To attain the object, the present invention includes the gas exhaust pipe disposed to be connected to the gas outlet port of the dry pump and to a gas inlet port of a detoxification device, and a heat exchanger which heats a diluent gas introduced therein using a heat generated from the dry pump and introduces the heated diluent gas into the gas exhaust pipe to heat a used gas to a temperature of not less than a predetermined value.

A gas pump including a delivery chamber with an inlet and an outlet for a gas. The delivery chamber is at least partially enclosed by a first housing part with a first sealing surface and a second housing part with a second sealing surface. A delivery device is moveable within the delivery chamber for delivering the gas. A pressing device presses one of the housing parts against the other with a pressing force such that the sealing surfaces abut each other and together form a sealing join which at least partially surrounds the delivery chamber in order to seal off the delivery chamber. The second housing part can be moved relative to the first housing part, against the pressing force, in order to be able to widen the sealing join to form a relieving gap through which liquid situated in the delivery chamber can escape.

A gas pump including a delivery chamber with an inlet and an outlet for a gas. The delivery chamber is at least partially enclosed by a first housing part with a first sealing surface and a second housing part with a second sealing surface. A delivery device is moveable within the delivery chamber for delivering the gas. A pressing device presses one of the housing parts against the other with a pressing force such that the sealing surfaces abut each other and together form a sealing join which at least partially surrounds the delivery chamber in order to seal off the delivery chamber. The second housing part can be moved relative to the first housing part, against the pressing force, in order to be able to widen the sealing join to form a relieving gap through which liquid situated in the delivery chamber can escape.

A portable vacuum pump with a lubricating oil system having a quick oil change system. The oil change system includes at least two containers of oil and a switch mechanism operable to initially place the first container in fluid communication with the vacuum pump to serve as the primary oil reservoir while isolating the second container from such fluid communication. Then in a snap action, the switch mechanism can be flipped to place the second container with clean oil in fluid communication with the vacuum pump to serve as the primary oil reservoir and isolate the first container from fluid communication when its oil becomes dirty, all while the vacuum pump is still operating to evacuate an AC/R system. The first container can then be removed, refilled with clean oil, and returned in place and the switch mechanism flipped back to it when the second container of oil becomes dirty.

A portable vacuum pump with a lubricating oil system having a quick oil change system. The oil change system includes at least two containers of oil and a switch mechanism operable to initially place the first container in fluid communication with the vacuum pump to serve as the primary oil reservoir while isolating the second container from such fluid communication. Then in a snap action, the switch mechanism can be flipped to place the second container with clean oil in fluid communication with the vacuum pump to serve as the primary oil reservoir and isolate the first container from fluid communication when its oil becomes dirty, all while the vacuum pump is still operating to evacuate an AC/R system. The first container can then be removed, refilled with clean oil, and returned in place and the switch mechanism flipped back to it when the second container of oil becomes dirty.

A dry type primary vacuum pump is provided, including at least two pumping stages mounted in series between a suction and a discharge of the pump; two rotors extending in the pumping stages and being configured to rotate synchronously in a reverse direction to drive a gas to be pumped between the suction and the discharge; an injection device configured to distribute a purge gas in at least one pumping stage, the injection device including at least one injector and at least one injection valve with an on or off control configured to be interposed between a purge gas supply source and the injector; and a control device configured to control opening and closing of the injection valve to inject a purge gas by successive pulses into the at least one pumping stage. A method for controlling the injection of a purge gas the vacuum pump is also provided.

A piston pressure device includes a gas concentration-regulating piston pressure device and a high temperature autoclave. In the gas concentration-regulating piston pressure device, the proportion and concentration of corrosive gases can be accurately adjusted, intermediate gases can be stored and filled into the high temperature autoclave according to experimental needs, and an actual corrosion process in oilfield is accurately simulated. Meanwhile, the corrosive gases can be supplemented in real time during the experiment, and dynamic gas distribution in a high-temperature high-pressure corrosion experiment process is realized. The present invention has the advantages as follows: the piston pressure device is resistant to high temperature and high pressure, corrosion-resistant, simple in structure and convenient to operate; the concentration and proportion of the corrosive gases are accurately controlled to be invariable in the high-temperature high-corrosion experiment process; and reliability of high-temperature high-pressure corrosive experimental results is increased.

A piston pressure device includes a gas concentration-regulating piston pressure device and a high temperature autoclave. In the gas concentration-regulating piston pressure device, the proportion and concentration of corrosive gases can be accurately adjusted, intermediate gases can be stored and filled into the high temperature autoclave according to experimental needs, and an actual corrosion process in oilfield is accurately simulated. Meanwhile, the corrosive gases can be supplemented in real time during the experiment, and dynamic gas distribution in a high-temperature high-pressure corrosion experiment process is realized. The present invention has the advantages as follows: the piston pressure device is resistant to high temperature and high pressure, corrosion-resistant, simple in structure and convenient to operate; the concentration and proportion of the corrosive gases are accurately controlled to be invariable in the high-temperature high-corrosion experiment process; and reliability of high-temperature high-pressure corrosive experimental results is increased.

A dry vacuum pump includes: at least one oil sump; at least one pumping stage; two rotary shafts respectively supporting at least one rotor extending into the at least one pumping stage, the rotors being configured to rotate in a synchronized manner in the reverse direction in order to convey a gas to be pumped between an intake and an outlet of the vacuum pump, the shafts being supported by bearings lubricated by a lubricant contained in the at least one oil sump; at least one lubricant sealing device interposed between the at least one oil sump and a pumping stage at the shaft passage; and at least one expansion device configured to reduce the pressure variations between a pumping side volume and the at least one oil sump.

A dry vacuum pump includes: at least one oil sump; at least one pumping stage; two rotary shafts respectively supporting at least one rotor extending into the at least one pumping stage, the rotors being configured to rotate in a synchronized manner in the reverse direction in order to convey a gas to be pumped between an intake and an outlet of the vacuum pump, the shafts being supported by bearings lubricated by a lubricant contained in the at least one oil sump; at least one lubricant sealing device interposed between the at least one oil sump and a pumping stage at the shaft passage; and at least one expansion device configured to reduce the pressure variations between a pumping side volume and the at least one oil sump.