Chell Instruments Ltd. products

THI Model HFM-200 Flowmeters with an LFE offer the user fast, accurate measurement of high-capacity gas flows, in ranges from 25 slm up to 15,000 slm. Our laminar flow elements (smoothed, flanged, or threaded) are available in various sizes from 3/8” up to 8”. Used in conjunction with the standard HFM Flowmeter, these units can be combined to measure full-scale flows up to 15,000 slm and feature a typical pressure drop of 4.5” of water at full-scale flow.

The HFM/HFC Series of flow instruments is based on a modular design. At the heart of each instrument is an insulated thermal transfer sensor which provides enhanced zero stability. This sensor is designed to be removable/replaceable in the field to virtually eliminate long down time due to clogging. Additionally, the HFM/HFC design features an integral filter and an easily replaceable closed loop electronics card.* The HFC also features a two-stage, pilot-operated control valve. All of these standard features, when coupled with the instrument’s inherent linear response to flow changes and THI’s long-proven reputation for quality, result in the finest flowmeters and flow controllers available today.

The THI Mass Flow 300 Metaline Series meters and controllers are designed to accurately measure mass flow without corrections or compensations for gas pressure and temperature. They are accurate to better than ±0.75% of full-scale for .005 to 10 slm and ±1.0% of full-scale for 10 to 25 slm. THI mass flow instruments do not require any periodic maintenance under normal operating conditions with clean gases. No damage will occur from the use of moderate overpressures (~500 psi) or overflows. Instruments are normally calibrated with the appropriate standard calibration gas (nitrogen), then a gas conversion factor (GCF) is used to adjust the output for the intended gas. Special calibrations for other gases, such as oxygen, helium and argon, are available upon special order.

The HFM/HFC Series of flow instruments is based on a modular design. At the heart of each instrument is an insulated thermal transfer sensor which provides enhanced zero stability. This sensor is designed to be removable/replaceable in the field to virtually eliminate long down time due to clogging. Additionally, the HFM/HFC design features an integral filter and an easily replaceable closed loop electronics card.* The HFC also features an externally adjustable valve with easily replaceable flow orifices. All of these standard features, when coupled with the instrument’s inherent linear response to flow changes and THIs’ long-proven reputation for quality, result in the finest flowmeters and flow controllers available today.