Radwag AVK 1000.5Y Automatic Vacuum Mass Comparator equipped with pumps

RADWAG-manufactured AVK-1000 automatic vacuum mass comparator is intended for national metrological institutes that transfer and maintain the national reference mass standard of 1 kg.

The comparator is intended for weighing mass standards and silicone spheres of 100 mm diameter. It enables comparison of up to 6 prototypes of max 1kg mass. The repeatability of the process is of 0.3 µg and readability of d = 0.1 µg.

A specially designed vacuum chamber enables carrying out measurements in a vacuum of 10-6 mbar capacity or in atmosphere containing noble gases.

AVK-1000 is equipped with suspended weighing pan that eliminates eccentricity errors.

Standard version of the mass comparator features thermo-hygro-barometer for testing ambient conditions with great accuracy: pressure of 0.001hPa, humidity of 0.01% and temperature of 0.001 °C. The comparator is also equipped with high quality vacuum gauge.

The AVK-1000 vacuum mass comparator can be equipped with the LOAD LOCK system for carrying mass standards. The system enables switching or adding artefacts without changing the atmosphere inside the main chamber. With the use of a special chamber for mass standards switching the whole process is 90% shorter. During mass standards replacement carried out without the use of the LOAD LOCK system, the air enters the main chamber of the mass comparator. After each opening of the chamber it is necessary to pump the air out in order to obtain required vacuum value. The vacuum mass comparator needs approx. 48 hours in order to obtain vacuum that ensures measurement repeatability.

The LOAD LOCK is equipped with a high-efficiency pump system, the time of pumping the air out in order to enable opening of the valve of the main chamber is significantly shortened. The stabilization of the main chamber after replacing/adding the mass standard and closing the valve connecting the main chamber and the LOAD LOCK system takes 5 hours.

The high-quality vacuum gauges enable monitoring and comparing the vacuum value in order to determine the moment when opening the valve again and replacing the mass standard is available. A specially designed viewfinder enables monitoring of the process.

The LOAD LOCK enables switching objects of dimensions adapted to the AVK-1000 mass comparator: cylindrical mass standards of 22-95 mm diameter and silicone spheres of 40-100 mm diameter.

Supplementing the AVK-1000 vacuum mass comparator with LOAD LOCK system significantly improves the comparison performance.