Weighing method

1. Scope of application

    The weighing method is recommended by the International Standardization Organization. It is only applicable to gases that do not react with each other or with the inner wall of the cylinder, and to condensable components that are completely in the gaseous state under experimental conditions.

2. Required equipment

    Distribution equipment: vacuum pump, vacuum gauge, high and low pressure gauge, valve, cylinder clamp, case.

Weighing equipment: high precision balance

osmosis

1. Scope of application

    Osmosis is suitable for preparing trace active gases. It is dynamic gas distribution method.

2. Required equipment

    Distribution equipment: seepage tube, pressure regulating valve, flow stabilizing system, flowmeter, temperature recording instrument, valve, pipeline, mixing tank.

The partial pressure method

1. Scope of application

The partial pressure method is suitable for preparing standard mixed gas with the content of 1~60% at room temperature

2. Required equipment

Distribution equipment: cylinder busbar, pressure gauge, valve, vacuum pump, pipeline, cylinder clamp.

Diffusion method

1. Scope of application

    Diffusion method is suitable for preparing organic gas which is liquid at room temperature

2. Required equipment

    Distribution equipment: cylinders, valves, flow control valves, flowmeters, liquid components, analytical instruments, cylinders, fixtures.

Volumetric method

1. Scope of application

    Static volume method is suitable for laboratory preparation of a variety of small and small amounts of standard gases, pressure close to atmospheric pressure.

2. Required equipment

    Distribution equipment: gas cylinder, gas cylinder relief valve, fixed volume tube, pressure gauge, vacuum pump.

Saturation method

1. Scope of application

    The saturation method is suitable for gases and vapors that are easy to condense.

2. Required equipment

    Distribution equipment: gas cylinder, gas cylinder relief valve, condenser, saturator, thermostat controller, pressure gauge, circulation fan.

Flow method

1. Scope of application

    The flow ratio method is a dynamic gas distribution method, which is a standard gas obtained by strictly controlling the flow rate of certain proportion of component gas and release and dilution gas.

2. Required equipment

    Cylinder, cylinder relief valve, check valve, flow controller, pressure gauge, pipe, case.

Dilution method

1. Scope of application

    Dilution method is one of the methods to prepare low content standard gas.

2. Required equipment

    Cylinder, cylinder relief valve, flow controller, pressure gauge, piping.

Volume method

1. Scope of application

    The volume ratio method is a simple gas distribution method, which is calculated by volume according to the required gas content. A standard gas that controls the volume of the constituent gases and the volume of the release diluent gases.

2. Required equipment

    Syringe, constant volume container.

calibration gas