1. Purpose and features

The JSY-WG elbow flowmeter is widely used for flow measurement in petroleum, chemical, power, light-industry, pharmaceutical, waterworks and district heating/cooling applications, and also measures high-temperature high-pressure steam. Simple in structure, with no inserted throttling element and no added pressure loss, easy to install and reliable, it suits especially large-bore, high-flow, loss-free, low-viscosity duties. Heat-resistant, wear-resistant, vibration-proof and maintenance-free.

2. Construction

Elbow flowmeter construction (Fig. 1)

Elbow flowmeter construction (Fig. 2)

3. Working principle

The elbow-meter measuring equation is:

qm = K · (π/4) · Dt² · √(2·ρ₁·ΔP)

where qm — mass flow, kg/h; Dt — pipe inner diameter at working temperature, m; ρ₁ — medium density at operating conditions, kg/m³; ΔP — differential pressure actually produced by the elbow meter, Pa; K — metering coefficient, computed and calibrated by wet-flow calibration.

4. Technical data

4.1 Measuring range:

• a. Tappings: 45° or 22.5° direction;
• b. Nominal bore: DN25–1000 mm;
• c. Nominal pressure: ≤ 4.0 MPa;
• d. Working temperature: ≤ 450℃;
• e. Velocity: gas 5–120 m/s, liquid 0.1–12 m/s;
• f. Reynolds number ReD: ≥ 10⁴;
• g. R/D > 1.25 (R — elbow curvature radius, D — pipe inner diameter);
• h. Accuracy class: 1 (calibrated), 4 (uncalibrated).

4.2 Installation: vertical or horizontal; vertical with flow upward.

4.3 Straight-run requirements: 22.5° tappings: L1=6D, L2=4D; 45° tappings: L1=L2=5D; both with two special flanges and root valves.

4.4 Model designation: JSY-WG (JSY — throttling device; WG — elbow flowmeter).

4.5 Supply scope: supplied fully assembled; complete the "Throttling Device Order Enquiry Form" when ordering.

4.6 Ordering conditions as for other throttling devices — see the enquiry form.

Related Reading

• JSY-BK Conditioning Orifice Plate
• JSY-BP Conditioning Nozzle
• JSY-YQ Segmental Orifice Plate