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Robotic Viscometer Automation under ASTM D7279

For the commercial oil-analysis lab that needs hundreds of kinematic-viscosity measurements per shift, run unattended overnight, with on-line PCS validation and the right tube selected automatically for every sample.

Built to standards
ASTM D7647 · D7279 · D5185
ISO 11171:2022
NIST SRM 2806d traceable
What it is

Houillon viscometry, automated

A Houillon viscometer is a capillary-tube viscometer geometry, originally developed in France, optimized for automated kinematic-viscosity measurement at 40°C and 100°C. A precise volume of sample falls through a narrow-bore glass capillary under gravity at controlled temperature; the time to fall between two optical sensors, multiplied by the tube’s calibrated factor, gives the kinematic viscosity in cSt (mm²/s). The same tube can be used over a defined viscosity range; tubes with different factors cover the rest.

The robotic automation layer — what CINRG’s CS-HVA adds — takes the Houillon baths (ISL/PAC viscometer baths in current installations) and surrounds them with an XYZ robot, a syringe pump, a wash station, automated solvent filling, and fuzzy-logic tube selection. Together, they convert what was previously a labor-intensive sequence of operator decisions into an unattended overnight run.

The relevant standard is ASTM D7279-14, “Standard Test Method for Kinematic Viscosity of Transparent and Opaque Liquids by Automated Houillon Viscometer.” D7279 is the modern alternative to the older ASTM D445 (manual U-tube capillary viscometry) for high-throughput laboratory use. The two methods produce equivalent kinematic-viscosity values; D7279 is significantly faster per sample and supports unattended operation.

How it works

The CS-HVA workflow

The CS-HVA processes a sample in roughly 40 seconds — 90–100 samples per hour. Each sample passes through this sequence inside the instrument:

  • Read the batch file row. Sample number, tray/rack position, expected viscosity at 40°C and 100°C, priority flag, operator ID. CSV format, importable from any LIMS.
  • Fuzzy-logic tube selection. Software matches the sample’s expected viscosity to the correct tube factor on the right bath at the right temperature. If the matching tube is busy, the sample queues. If no compatible tube is currently in service, the sample is skipped and retried later. This eliminates manual tube-selection error.
  • Sample pickup. The robotic XYZ axes position the syringe over the sample cup. The level sensor tracks the falling oil surface during uptake to minimize wetted needle surface. Less than 1 mL of sample is required.
  • Inject into tube. The syringe doses the sample into the selected viscometer tube under controlled conditions. A level sensor at the tube confirms successful fill.
  • Capillary measurement. Sample falls through the capillary at the bath temperature. Two optical sensors record the start and stop times. The bath controller multiplies elapsed time by the tube’s calibrated factor to compute kinematic viscosity.
  • Validate. If the analysis time falls outside the configured lower or upper bound (typically 30–90 sec), the system flags non-conformance and either retests or routes the result to a separate non-conforming file per the lab’s ASTM compliance setting.
  • Wash. Needle returns to the wash station: six 45° solvent jets clean inside and outside surfaces, drying pad removes residual solvent, drip comb prevents fluid bridging. Constant solvent pressure from auto-filled reservoirs makes the cleaning cycle reproducible from sample to sample.
  • Write results. KV40 / KV100 / both, plus operator name, lab/sample number, date/time, bath number, tube number, minimum and maximum tube time, raw analysis times. CSV output to single and batched daily files.

Process-control standards (PCS) interleave automatically through the run. Each tube can be configured with up to 2 PCS; the 4-bath system supports up to 16 PCS in total. If a PCS measurement falls outside its configured upper or lower threshold, the tube is automatically locked out of service, prior samples on that tube are quarantined to a fail directory, and the remaining tubes continue running unaffected.

Configuration

CS-HVA-2 (2-bath) vs CS-HVA-4 (4-bath)

The decision is throughput-driven.

CS-HVA-2 (2-bath) CS-HVA-4 (4-bath)
Bath count24
Typical temperature setup1 × 40°C, 1 × 100°C2 × 40°C, 2 × 100°C
Sample throughput~600 measurements / 8-hr shiftUp to 1,200 measurements / 8-hr shift
Sample capacity (per load)Up to 4 trays of 200 = 800 samplesUp to 4 trays of 200 = 800 samples
PCS configurationUp to 8 (2 per tube × 4 tubes typical)Up to 16 (2 per tube × 8 tubes typical)
Footprint~7 ft / 214 cm wide~10 ft / 320 cm wide
Weight~300 lb / 136 kg~500 lb / 226 kg
Right forLabs under ~400 samples/dayLabs at 600+ samples/day or running both KV40 and KV100 in parallel

Both configurations share the same software, same fuzzy-logic tube assignment, same wash station, same multi-point calibration support, and the same ISO/IEC 17025 validation track record. The choice is throughput, not capability. If your lab volume is under 400 samples per day, the CS-HVA-2 has plenty of headroom. If you regularly run 600+ samples or want to clear the day’s queue overnight, the CS-HVA-4 doubles the parallel capacity.

Field record

What customers have seen

WearCheck Canada
“The CINRG robotic viscometer system has improved repeatability of viscosity results and freed up close to one full day of technician time. A definite win-win for our laboratory.”
Frank PerriWearCheck Canada, Toronto
Tekniker · Spain
“After two months working with the CS-HVA-1 we think it is, by far, the biggest advance in automation we have in our labs. We are fully satisfied with its performance and results.”
Jose IgnacioTekniker, ISO/IEC 17025-accredited testing laboratory
ISO/IEC 17025 validation
“CINRG CS-HVA validation runs against Conostan certified standards produced internal-standard sample populations of n=196 with measured KV40 and KV100 values consistently inside the ±2% certified bounds.”
CINRG technical validationData available on request as basis for customer-side ISO 17025 method validation
Frequently asked

Common questions about robotic viscometer automation

What is a robotic Houillon viscometer?

A Houillon viscometer is a capillary-tube viscometer designed for kinematic-viscosity measurement at 40°C and 100°C. A robotic Houillon viscometer adds an XYZ robot, syringe pump, and wash station that automate the sample handling — letting the lab run hundreds of samples per shift unattended under ASTM D7279-14.

What is ASTM D7279?

ASTM D7279-14 is the Standard Test Method for Kinematic Viscosity of Transparent and Opaque Liquids by Automated Houillon Viscometer. It defines the operation of automated Houillon-type capillary viscometers at 40°C and 100°C and is the modern alternative to ASTM D445 (manual U-tube capillary) for high-throughput lab use. The two methods produce equivalent kinematic-viscosity values.

What throughput should I expect from a robotic viscometer automation system?

CINRG’s CS-HVA loads a sample every 40 seconds (~90 samples/hour). A 2-bath CS-HVA-2 delivers up to ~600 viscosity measurements per 8-hour shift; a 4-bath CS-HVA-4 doubles that to up to 1,200 measurements per shift. Both run unattended overnight with auto-solvent filling and idle-timeout pump shutdown.

How does fuzzy-logic tube selection work?

Each sample in the batch file carries an expected viscosity at 40°C and 100°C. The CS-HVA software assigns the sample to the correct viscometer tube factor automatically. If the right-factor tube is busy, the system queues the sample. If no suitable tube is currently in service, the sample is skipped and retried later when a matching tube is free. This eliminates the operator-error mode of selecting the wrong tube and producing an out-of-bounds analysis time.

Can a robotic viscometer report KV40 and KV100 simultaneously?

Yes. Bath temperature is set per-bath. A typical 4-bath configuration runs two baths at 40°C and two at 100°C, producing both KV40 and KV100 in the same overnight run. KV100 accuracy benefits significantly from multi-point calibration, which the CS-HVA software supports natively.

What is the carry-over between samples?

Negligible. The syringe minimizes wetted surface during sampling; after dispensing, the needle is washed at a six-jet station with solvent plus mechanical agitation and a drying pad. Automated solvent filling holds the cleaning reservoirs at constant level for reproducible rinse pressure. CINRG ISO/IEC 17025 validation runs show internal-standard distributions tightening significantly after CS-HVA installation versus prior manual workflows.

Looking at robotic viscometer automation?

Tell us your daily sample volume, KV40/KV100 split, and bath preference. A CINRG engineer will help you choose between the CS-HVA-2 and CS-HVA-4.

Request a Quote View CS-HVA Specs
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