This kit simplifies the operation of MMR’s micro miniature refrigeration systems, providing a valve for the pump line, a vacuum gauge to monitor the pressure in the Dewar, and an up-to-air valve. For additional information on the Vacuum Accessory Kit — click here.
This convenient kit contains sundry aids to assist you in mounting samples on the refrigerator cold pad. For additional information on the Sample Mounting Kit — click here.
MMR’s two-stage mechanical pump provides a consistent vacuum of better than 5 milliTorr at the Dewar.
A vacuum chamber pressure of 8 milliTorr or better is ideal for the operation of the MMR Technologies Joule-Thomson cryogenic cooling system and thermal isolation of the device under analysis. A two-stage roughing pump with a pumping speed of at least 90 liters per minute (3.18 cfm, 5.3 cmm) is suggested for this application. This pump should be operated with no air injection or bleed.
For additional information on Vacuum Pumps — click here.
A filter/dryer system is necessary to remove both the water and the other condensable contaminants, to ensure optimal performance of the Joule Thomson refrigerators. Failure to use one of these systems in conjunction with your cooling system will ultimately result in a loss of cooling capacity, reduction in the temperature range the micro miniature refrigerator can obtain, clogging in the channels of the glass refrigerator, and ultimately, damage to these channels which may not be repairable.
MMR Technologies supplies two possible configurations for the filter-dryers. Each system is designed to work with the company’s line of micro miniature Joule-Thomson refrigerators.
The high pressure gas regulator must be able to deliver gas at pressures of 1800-1900 psi. Typically the upper limit is 2500 psi. It must be able to accommodate the maximum pressure of the gas tank when it is initially delivered in the cylinder. Typically the upper limit is 3000 psi. Special regulators are available to be used with cylinders with even higher delivery pressures. It is best to consult with the supplier of the high pressure nitrogen gas to make sure that the regulator is compatible with the gas cylinders in which the gas will be delivered.