Venturi · Nozzle

Flow Nozzle Flow Nozzle (ISO 5167 Long Radius)

MODEL : DHON-BW / DHON-HR / DHON-FL
An ISO 5167 long radius (Long Radius) type flow nozzle. Suitable for measuring the flow of high-temperature, high-pressure fluids, it has higher mechanical strength than an orifice of the same bore and passes more flow. Supplied as weld-in, holding ring and flanged types, and as an integral meter run.

Product Overview

Flow Nozzle (ISO 5167 Long Radius)

Flow Nozzle DHON (long radius nozzle and meter run)
DHON-BWDHON-HRDHON-FL

Although a flow nozzle costs more than an orifice because of its construction, it is suitable for measuring the flow of fluids at high temperature and high pressure.

Under the same measuring conditions, a flow nozzle has higher mechanical strength, can pass more than 60% more flow than an orifice of the same bore, and measures fluids containing solid particles with less disturbance than an orifice. It is therefore also suitable for high-velocity fluids.

Supplied not only as a nozzle alone but also as a meter run with short pipe sections welded on both the upstream and downstream sides.

2B ~ 24B (50A ~ 600A)β 0.2 ~ 0.8Accuracy ±2.0%1D - 1/2D taps
English description

The Flow nozzles, more costly than other orifice due to their structure, are suited for determining the flow rates of fluids flowing at high temperature and high pressure. Under the same measuring conditions, a flow nozzle has a higher mechanical strength, can permit the flow of more than 60 percent greater volume of a fluid, and can measure the flow rates of fluids containing solid particles less disturbed, than an orifice having the same bore. Thus, they are suited, in addition, for highspeed flowing fluids. We can supply not single flow nozzles, but also flow nozzles having welded short pipes on both their upstream and downstream sides.

Measurement principle

Differential-pressure structure and flow relationship

Long radius nozzle shape — High ratio (0.25 ≤ β ≤ 0.8) · Low ratio (0.2 ≤ β ≤ 0.5)
Long radius nozzle shape — High ratio (0.25 ≤ β ≤ 0.8) · Low ratio (0.2 ≤ β ≤ 0.5)

The long radius nozzle consists of an elliptical (quarter-ellipse) convergent section and a cylindrical throat of length 0.6d, with differential pressure sensed at taps located 1D upstream and 1/2D downstream (1D-1/2D taps).

Depending on β (= d/D), nozzles are classified as high ratio (0.25 ≤ β ≤ 0.8) or low ratio (0.2 ≤ β ≤ 0.5), and their shapes differ.

Types · model configuration

Specification comparison by model

The three images are cutaway renderings with the pipe cut lengthwise to show the installation method; the actual products are closed pipe / meter-run sections.

FIG 1 Weld in type · FIG 2 Holding Ring type · FIG 3 Flange type
FIG 1 Weld in type · FIG 2 Holding Ring type · FIG 3 Flange type
ItemDHON-BW
Weld-in type (Weld in)
DHON-HR
Holding ring type (Holding Ring)
DHON-FL
Flanged type
FeaturesButt welding mounting type (Weld in type, FIG 1)Holding ring mounting type (Holding Ring type, FIG 2)Flange mounting type (Flange type, FIG 3)
Turndown6:16:16:1
MaterialsCarbon Steel, STS304, STS316, Inconel, Monel, HastelloyCarbon Steel, STS304, STS316, Inconel, Monel, HastelloyCarbon Steel, STS304, STS316, Inconel, Monel, Hastelloy
ConnectionButt WeldButt WeldFlange 150#, 300#, 600#, 900#, 1500#, 2500#
Applicable piping2B ~ 24B (50A ~ 600A) Pipe2B ~ 24B (50A ~ 600A) Pipe2B ~ 24B (50A ~ 600A) Pipe
StandardsISO5167-3ISO5167-3ISO5167-3
Accuracy±2.0%±2.0%±2.0%

Technical Specifications

Detailed conditions are confirmed at quotation.

ItemValue
Accuracy±2.0%
Turndown6:1
Mounting typeISO 5167 Long Radius — Weld in type (FIG 1) · Holding Ring type (FIG 2) · Flange type (FIG 3)
Flow calculation standardISO5167, JIS Z 8762, ASME, KS A 0612
Pressure taps1D - 1/2D taps
Applicable pipe sizes2 to 24B (50A to 600A)
β range0.2 ≤ β ≤ 0.8 — Low beta long radius nozzle 0.2 ≤ β ≤ 0.5 · High beta long radius nozzle 0.25 ≤ β ≤ 0.8
Nozzle materialCarbon Steel · 304SS, 304L SS, 316SS, 316L SS · Ni, Cr, Mo Alloy Steel (A182 F11 to 91)
Meter run materialA53 Gr B · A106 Gr B · A335 P11 · A335 P22 · A335 P51 · A335 P91
Flange rating150#, 300#, 600#, 900#, 1500#, 2500# (DHON-FL)
DP tap connectionNPT 1/2 · NPT 3/4 · SW 1/2 · SW 3/4
Holding ring type meter runUpstream 4D (MIN.) · downstream 2D (MIN.) · reducer angle 30° Max · splice weld required to maintain the minimum downstream length per A.S.M.E. Fluid Meters
Weld-in type noteFor sizes under 3", the downstream connection weld may overlap the nozzle/pipe weld

Standards

Installation requirements

Straight run and installation notes

Ordering information (How to Order)

You can request a quotation by combining the model codes.

Model (DHON-)

BWWeld in type
HRHolding Ring type
FLFlange type

Meter Run

NElement Only (nozzle only)
YMeter run Include (meter run included)

Nominal Pipe Size

□□□Pipe size in inch or mm (nominal pipe size, inch or mm)

Nozzle Material

A1A105
4SA182 F304
4LA182 F304L
6SA182 F316
6LA182 F316L
11A182 F11
22A182 F22
51A182 F51
91A182 F91
OPOption

Meter Run Material

A5A 53 Gr B
10A 106 Gr B
P1A 335 P11
P2A 335 P22
P5A 335 P51
P9A 335 P91
00Option

Diff' Taps

1NPT 1/2
2NPT 3/4
3SW 1/2
4SW 3/4

Flange Type

000Flange Rating (specify flange rating)

Option

/□□□Options (by separate agreement)

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We can help with specification review and quotation

Tell us the pipe size, fluid, pressure / temperature and flow range, and we will propose a suitable model and a flow calculation sheet.

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Tel 031-357-8431 (Sales, ext. 1) · Fax 031-357-8432