Patented differential pressure flow measurement

Precision flow measurement for compact, high-pressure, and harsh industrial service.

The SPINDLE flowmeter combines an engineered primary element, integrated flow conditioning, and factory calibration to deliver stable measurement where conventional meters need long straight pipe, frequent maintenance, or higher permanent pressure loss.

Turndown

Up to 500:1

Line size

DN8-DN4000

Temperature

-200 C to +850 C

Pressure

PN400 / Class 2500

Installed Base

3,000+ units

Patented technology across multiple continents — 3 patents granted

SPINDLE flowmeter primary element with pressure and temperature transmitters, packaged for field deployment

Industrial Benefits

Zero straight-pipe penalty

Built-in flow conditioning allows installation directly after elbows and in compact skids, offshore modules, shipboard systems, and crowded plant rooms.

Lower operating cost

Permanent pressure loss is approximately one quarter of a standard orifice plate, reducing pumping or compression energy demand.

Harsh-service reliability

All-metal construction, no internal moving parts, and optional abrasion-resistant materials support high-pressure, particulate, wastewater, and crystallization-prone fluids.

Long service life via wide turndown

A turndown ratio of up to 500:1 keeps the meter accurate as process flow rates shift over time, extending useful service life without re-sizing or early replacement.

Applications

  • Offshore production platforms, topside modules, and FPSO packages
  • Onshore oil and gas production, drilling, and gas gathering stations
  • Midstream pipelines, gas terminals, and underground storage facilities
  • Marine and shipboard utility systems
  • Hydrogen, compressed air, flue gas, dirty gas, steam, and wastewater service
  • Research laboratories, wind tunnels, and high-pressure test platforms

Special Service Options

Available for slurry and particulate flow, bidirectional measurement, and dual- or triple-redundant configurations for SIS-oriented deployments.

Engineering Evidence

Design Requirements

  • Field and laboratory environments should be hydrodynamically similar — matching Reynolds number, Mach number, and velocity profiles.
  • Permanent pressure loss must be minimized to reduce energy cost and avoid disturbing the pipeline system.
  • The meter must tolerate unclean process fluids through self-cleaning flow paths.
  • The discharge coefficient should remain constant wherever possible, avoiding piecewise approximation or iterative correction errors.

Technical Approach

  • Built on differential-pressure measurement, using a purpose-designed throttling element to control and reshape the internal flow field.
  • Flow is conditioned inside the meter so that field conditions match calibration conditions — eliminating the need for straight pipe upstream or downstream.
  • Wide measurement range from sub-critical to critical flow regimes.
  • Throttling element geometry optimized through computational fluid dynamics (CFD) and genetic algorithms to prevent flow separation, stabilize the flow field, and minimize drag.
  • Spindle-shaped throttling body with front and rear support fins to straighten flow, provide structural stiffness, and resist shock waves in gas or water hammer in liquid service.

Dimensional analysis shows the discharge coefficient depends only on Reynolds number, and the expansibility factor depends only on Mach number — allowing independent, predictable characterization across operating conditions.

Numerical simulation confirms smooth flow throughout the meter body with only minor separation at the tail cone. Pressure and velocity recover quickly with a short wake, minimizing downstream disturbance. The annular channel re-establishes boundary layers on both sides of the spindle; as Reynolds number increases, the boundary layer thins and the discharge coefficient stabilizes to a constant value.

The meter can convert asymmetric inlet flow — such as flow from an elbow — into uniform, axis-symmetric flow without external straight-run piping.

SPINDLE flow meter cross-section showing central body, fins, and pressure taps
Cross-section — spindle body, support fins, and differential pressure taps
CLJ SPINDLE flow meter assembly with labeled components
Product assembly — measuring tube, throttling spindle, and pressure connections
CFD simulation of annular channel velocity profiles
Annular channel CFD — velocity profiles in the measurement gap
CFD pressure contour around spindle throttling element
Pressure contour — flow acceleration at the channel throat

Datasheet & Calibration

SeriesSPINDLE
Measurement PrincipleDifferential pressure (annular channel)
Accuracy — LiquidBetter than 0.15%
Accuracy — GasBetter than 0.3%
RepeatabilityBetter than 0.1%
Turndown Ratio13:1 standard; up to 500:1
Pipe Size1/4 in to 160 in (DN8 – DN4000)
Operating Temperature-200 °C to 850 °C
Maximum PressurePN 400 (GB); Class 2500 (ASME)
Applicable FluidsLiquid, gas, steam (Re > 2,000)
Straight-Run RequirementNone (upstream or downstream)
Pressure Loss¼ standard orifice plate equivalent
Moving PartsNone in measuring body
CalibrationFactory flow calibration; coefficient stored in electronics
Verification StandardJJG 640
Flange StandardsGB/T 9119, GB/T 9115, ASME B16.5
Typical ModelSPINDLE-200-D5-AS-Q-02

Sample Gas Uncertainty

Qmax

0.13%

0.7 × Qmax

0.09%

0.4 × Qmax

0.14%

0.3 × Qmax

0.12%

Calibration Facilities

  • NIM (China) — Water facilityDN50 channel flow meter calibrated on national water flow standard.
  • PTB (Germany) & CEESI (USA)DN80 gas calibration at Re > 10⁵
  • Jiangsu Gas Flow Center (China)DN80 calibration on PVTt gas flow facility.
  • PTB (Germany) — With elbow upstreamDemonstrated accurate measurement with elbow connected directly, no straight run.
  • Siemens Coriolis meter — Series comparisonExcellent correlation in side-by-side testing; any system offset attributable to different transfer standards.

Signal Interface

Measured Signals

  • Flow rate
  • Pressure
  • Temperature

Outputs & Protocols

  • 4-20 mA analog output
  • 24 V pulse output
  • RS-485 digital bus
  • TCP/IP or custom protocols on request

Technology Comparison

SPINDLE is positioned for compact installations and harsh operating conditions where conventional differential-pressure, target, and clamp-on ultrasonic meters face pressure-loss, straight-run, coupling, or maintenance limitations.

SPINDLE Flowmeter
Measurement Principle
Differential Pressure (Channel Type)
Typical Accuracy
+/-0.50%
Repeatability
+/-0.10%
Turndown Ratio
500:1
Pressure Loss
Low (approx. 1/4 of Orifice)
Upstream Straight Pipe
None Required
Downstream Straight Pipe
None Required
Flow Conditioning
Strong (Built-in)
Installation Sensitivity
Low
Flow Profile Robustness
Excellent
Accuracy Stability in Field
Excellent
Pressure Rating
Very high
Moving Parts
No
Coupling Medium Needed
No
Fouling / Wear Risk
Low
Calibration Dependency
Low
Maintenance Cost
Near Zero
Bidirectional Measurement
Yes
Orifice Plate
Measurement Principle
Differential Pressure
Typical Accuracy
1-2%
Repeatability
0.2-0.5%
Turndown Ratio
~10:1
Pressure Loss
Very High
Upstream Straight Pipe
10-20D
Downstream Straight Pipe
5-10D
Flow Conditioning
None
Installation Sensitivity
High
Flow Profile Robustness
Poor
Accuracy Stability in Field
Moderate
Pressure Rating
Very high
Moving Parts
No
Coupling Medium Needed
No
Fouling / Wear Risk
Medium-High
Calibration Dependency
High
Maintenance Cost
Medium
Bidirectional Measurement
Limited
Target Flowmeter
Measurement Principle
Force / Mechanical
Typical Accuracy
1.5-5%
Repeatability
0.10%
Turndown Ratio
10:1
Pressure Loss
Medium
Upstream Straight Pipe
5D
Downstream Straight Pipe
3D
Flow Conditioning
Limited
Installation Sensitivity
Medium
Flow Profile Robustness
Moderate
Accuracy Stability in Field
Moderate
Pressure Rating
High
Moving Parts
Yes
Coupling Medium Needed
No
Fouling / Wear Risk
High
Calibration Dependency
Medium
Maintenance Cost
High
Bidirectional Measurement
Yes
Clamp-on Ultrasonic
Measurement Principle
Transit-Time Ultrasonic
Typical Accuracy
2-5%
Repeatability
0.2-0.5%
Turndown Ratio
Up to 150:1*
Pressure Loss
None
Upstream Straight Pipe
30D
Downstream Straight Pipe
10D
Flow Conditioning
None
Installation Sensitivity
High
Flow Profile Robustness
Moderate
Accuracy Stability in Field
Moderate
Pressure Rating
Limited
Moving Parts
No
Coupling Medium Needed
Yes
Fouling / Wear Risk
Low
Calibration Dependency
Medium
Maintenance Cost
Medium
Bidirectional Measurement
Yes
V-Cone Flowmeter
Measurement Principle
Differential Pressure
Typical Accuracy
0.5-1%
Repeatability
0.15-0.3%
Turndown Ratio
10-20:1
Pressure Loss
Medium
Upstream Straight Pipe
3-10D
Downstream Straight Pipe
2-5D
Flow Conditioning
Partial
Installation Sensitivity
Medium
Flow Profile Robustness
Good
Accuracy Stability in Field
Good
Pressure Rating
High
Moving Parts
No
Coupling Medium Needed
No
Fouling / Wear Risk
Low
Calibration Dependency
Medium
Maintenance Cost
Low
Bidirectional Measurement
Yes

Deployment & Commercial Support

More than 200 clients and 3,000 installed units across oil and gas, chemical, steel, power, research, and utility applications.

Field Deployment Case Study

Changqing Oilfield (CNPC / PetroChina)

Installations

10+ operational sites

Product line

CLJ Segment Series, DN50-DN100

Process pressure

Up to 20-25 MPa

Flow range

50 to 50,000 Nm3/h

Key Achievements

  • Stable performance in high-pressure upstream environments
  • Reliable operation across multiple gas gathering stations
  • One platform covering a wide dynamic flow range
  • Proven robustness under harsh field conditions

Customer Impact

  • Standardized measurement across sites
  • Improved monitoring reliability in production and transmission
  • Reduced need for multiple instrument types
SPINDLE flowmeter with explosion-proof transmitter enclosure at a gas gathering station
Wellhead gas gathering station — explosion-proof instrumentation package
Multiple SPINDLE flowmeters installed on an outdoor metering skid
Multi-meter metering skid — outdoor custody transfer installation
SPINDLE flowmeter installation operating in sub-zero winter conditions
Cold-climate deployment — stable operation in sub-zero conditions
Large-diameter SPINDLE flowmeter body being loaded for shipment
Large-diameter fabrication — up to DN4000 for major pipeline service
ReferenceMediumApplicationSize Range
Sinopec Shandong Shengli OilfieldNatural GasWellhead MeasurementDN50, DN80, DN100, DN150
PetroChina Shaanxi Changqing Oilfield30 MPa Natural GasWellhead MeasurementDN32, DN50, DN65, DN80, DN100
Jiangsu Taixing Guangming ChemicalHydrogenCustody TransferDN150
Jiangsu Shagang GroupDirty GasCustody TransferDN720, DN820, DN900, DN1200, DN2800, DN3200
Changzhou Yabang ChemicalAirUtility ServicesDN1200
Jiangsu Hailan Thermal Power PlantAirUtility ServicesDN159, DN426, 600×900, 1000×1000
Chuzhou Yueda GroupAirUtility ServicesDN80
Zhengzhou Machinery Research Institute16 MPa AirTest PlatformDN50, DN100
Nanjing University of Aeronautics & Astronautics (Energy)Engine AirFuel Efficiency TestingDN50, DN80
China Aerodynamics Research Center (Mianyang, Sichuan)22 MPa Compressed Air, HydrogenWind Tunnel Arrays ExperimentsDN40, DN50, DN60, DN80, DN125, DN200, DN400, DN600, DN800
Nanjing Railway Locomotive Depot (East)Maintenance WastewaterDischarge MonitoringDN100
PetroChina Langfang Yong 22 Gas StorageNatural GasWellhead MeasurementDN200
Nanjing Chemical Industry ParkCompressed AirCustody TransferDN350
Nanjing Titanium Dioxide ChemicalCompressed AirCustody TransferDN350
CNPC Hutubi Underground Gas StorageNatural GasLargest underground gas storage facility in Asia — storage & withdrawal measurementMultiple
CNPC Huabei Balixi CCUS ProjectCO2Carbon Capture, Utilization & Storage (CCUS) measurementMultiple
China Oil & Gas Piping Network — Caiyu StationNatural GasMidstream Gas DistributionMultiple
Zhangjiagang Shazhou Steel PlantFlue GasEmissions MeasurementMultiple

Project Roadmap

Phase 1

Requirement survey and process data review

Phase 2

Sizing, design, material selection, and commercial quotation

Phase 3

Manufacturing, factory calibration, and documentation

Phase 4

Installation guidance, commissioning, and lifecycle support

Start RFQ

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