About Aalborg brand traffic

1. Basic equipment information

Brand/Model: Aalborg PMR1-018383

Aalborg is an international manufacturer of fluid control equipment, with its mass flow meters and controllers widely used in laboratories, industry, and medical fields.

Type speculation: Based on the model prefix 'PMR', it may belong to the Thermal Mass Flowmeter, which is a typical product line of Aalborg.

2. Core working principle

Thermal mass flow measurement technology

sensor structure

Contains two temperature sensors (RTD or thermocouple) and a heating element, both in contact with the fluid.

Typical layout: One sensor detects fluid temperature (T1), while the other is maintained by a heating element to maintain a fixed temperature difference (Δ T).

Measuring principle

When there is no fluid flow: the power of the heating element is constant, and the temperature difference between the two sensors is stable.

When fluid flows, the flow carries away heat, causing the upstream sensor (T1) to cool down and the downstream sensor (T2) to heat up. The heating power required to maintain Δ T is proportional to the mass flow rate (King's Law).

signal processing

Measure the change in heating power through the circuit and convert it into a standard signal output (such as 4-20mA or digital communication).

3. Key characteristics

Direct mass flow measurement: No temperature/pressure compensation required, suitable for precise gas measurement.

Low flow sensitivity: capable of detecting small flow changes (such as sccm level).

Low pressure drop: No mechanical components, reducing system resistance.

4. Possible design of model PMR1-018383

Range: Please refer to the manual, but the typical Aalborg thermal flowmeter covers a range of 0.5~500 SLPM (gas).

Material compatibility: 316L stainless steel or special alloy, suitable for corrosive gases.

Output options: Analog signal or RS-485 communication, supporting process control integration.

5. Application scenarios

Laboratory: Reaction gas flow control (such as semiconductor processes).

Medical: gas delivery for ventilators and anesthesia machines.

Industry: burner gas ratio, environmental monitoring.

6. Technical advantages

High repeatability: ± 0.5% reading accuracy.

Quick response: millisecond level dynamic adjustment.

Maintenance free: No moving parts, long lifespan.

Precautions

Gas calibration: It is necessary to calibrate according to the actual gas used (such as different calibration curves for N ₂ and O ₂).

Installation requirements: Avoid vibration/insufficient straight pipe section affecting accuracy.