Company Profile

Flow Meter Medical: Thorpe Tube Oxygen and Gas Administration Regulators

Quick Answer: A Thorpe tube flowmeter is a variable area device used in hospitals to control and measure oxygen delivery to patients. Silver Automation Instruments supplies precise, durable Thorpe tube regulators for wall outlets, anesthesia machines, and transport ventilators. Typical accuracy is ±10% of full scale, with flow ranges from 0–15 L/min and inlet pressures up to 200 bar.

What Is a Thorpe Tube Flowmeter?

A Thorpe tube flowmeter includes a tapered glass tube, a float (ball or bobbin), and an inlet pressure regulator. Gas enters from the bottom, lifts the float, and the float position shows flow rate on a calibrated scale. A clear polycarbonate cover protects the tube. These meters handle oxygen, medical air, and nitrous oxide in clinical setups.

How Thorpe Tube Regulators Work in Medical Gas Systems

The device connects to a 50 psi (4 bar) source, normally a hospital pipeline or cylinder regulator. Inside the body, a needle valve adjusts flow. The operator turns a knob to change orifice size, the float moves, and the scale reads directly in L/min. Because the outlet is unpressurized, the meter delivers gas safely to cannulas, masks, or humidifiers. Most engineers skip the theory and go straight to the spec sheet. Check the float material, flow range, and inlet pressure rating before ordering. We have seen many customer sites in Vietnam and Indonesia where a 0–15 L/min Thorpe tube with a barbed outlet is the bedside standard.

Key Specifications for Clinical Oxygen Flow Measurement

Standard flow ranges: 0–3 L/min for pediatric use, 0–15 L/min adult, and 0–25 L/min for high-flow applications. Accuracy is ±10% of full scale, which is enough for oxygen therapy. Flow tube material can be glass or polycarbonate; the float is typically stainless steel, black glass, or aluminum. Connectors follow DISS (Diameter Index Safety System) or NIST (Non‑Interchangeable Screw Thread) to prevent misconnections. Inlet pressure ranges from 280 to 600 kPa (40–87 psi). A built-in safety relief valve is included in many designs. Silver Instruments provides Thorpe tube regulators with brass chrome‑plated bodies and polycarbonate outer covers, ready for wall rail mounting or direct cylinder connection.

Silver Instruments Medical Flow Solutions

Silver Automation Instruments manufactures Thorpe tube oxygen flowmeters for hospitals, clinics, and home care providers across the Middle East, Latin America, and Southeast Asia. Our model SIMT-15 covers 0–15 L/min, with a brass body, polycarbonate cover, and a dual scale (L/min and L/min at STP). Inlet connection is DISS 1240, outlet is a 9 mm hose barb. We also supply spare flow tubes, floats, and needle valves. For bulk orders, skip the general inquiry. Send us your inlet pressure, outlet connection type, expected monthly quantity, and gas type. Download detailed datasheets at flow-meter.com.au. Contact us: Email [email protected], Tel +86-25-68650347, WhatsApp +86-25-52155837, WeChat +86 15365082610.

FAQ

Can Thorpe tube flowmeters measure gases other than oxygen?
Yes, they are used for medical air and nitrous oxide, but each gas needs a dedicated flowmeter with a specific connector index to avoid misconnections. Always confirm compatibility with the gas supplier.

What separates a Thorpe tube from a standard rotameter?
A Thorpe tube flowmeter is a rotameter designed for medical oxygen delivery, with a built-in regulator and safety features such as a pressure‑compensated needle valve. Industrial rotameters lack these medical‑grade locks and low‑pressure outlets.

How often should hospital oxygen flowmeters be calibrated?
Hospitals often do an annual calibration check. In dusty environments or after an impa