PULUODY PLD-4929A Lubricating Grease Dropping Point Tester
| Brand | PULUODY |
|---|---|
| Origin | Shaanxi, China |
| Manufacturer Type | Direct Manufacturer |
| Country of Origin | China |
| Model | PLD-4929A |
| Heating Power | 0–300 W (continuously adjustable) |
| Stirring Speed | 375 rpm |
| Supply Voltage | AC 220 V, 50 Hz |
| Illumination Lamp | 7 W |
| Oil Bath Capacity (Inner) | 600 mL |
| Compliance | GB/T 4929, ISO 2176, ASTM D566 |
Overview
The PULUODY PLD-4929A Lubricating Grease Dropping Point Tester is a precision-engineered instrument designed for the standardized determination of the dropping point of lubricating greases—defined as the temperature at which the grease transitions from a semi-solid to a liquid state under controlled heating and gravitational conditions. Based on the fundamental principle of thermal transition measurement in a calibrated oil bath environment, the PLD-4929A implements a standardized test protocol aligned with internationally recognized methodologies: GB/T 4929 (China National Standard), ISO 2176 (International Organization for Standardization), and ASTM D566 (American Society for Testing and Materials). This apparatus operates via a regulated conductive oil bath system wherein a grease-filled cup is heated at a defined rate while continuously stirred; the onset of continuous drip flow through the cup’s orifice is visually observed and recorded as the dropping point. The instrument is engineered for reproducibility, operator safety, and long-term stability—making it suitable for routine quality control in lubricant manufacturing, R&D laboratories, petroleum refineries, defense logistics depots, and transportation maintenance facilities.
Key Features
- Integrated dual-chamber oil bath: Inner chamber—a 600 mL borosilicate glass flask—ensures uniform thermal distribution; outer jacket provides thermal insulation and leak containment.
- Adjustable heating system: Solid-state voltage regulator enables precise 0–300 W power control, delivering consistent ramp rates compliant with ASTM D566 requirements (typically 5–6 °C/min).
- Constant-speed magnetic stirring: Fixed 375 rpm agitation maintains homogeneous temperature throughout the bath and prevents localized superheating near the heater surface.
- Standard-compliant temperature measurement interface: Precision-machined thermometer support assembly features O-ring sealing (oil-resistant nitrile rubber), threaded locking mechanism, and softwood guide ring for accurate immersion depth control per ISO 2176 Clause 6.2.
- Optimized visual observation: Integrated 7 W cold-light illumination ensures high-contrast viewing of drip initiation without introducing radiant heat interference.
- Compact benchtop architecture: All subsystems—including heating element, stirrer motor, lamp, and control circuitry—are integrated into a single robust chassis with minimal footprint and intuitive front-panel operation.
Sample Compatibility & Compliance
The PLD-4929A accommodates standard ASTM/ISO-compliant grease cups (e.g., brass or stainless steel, 12.7 mm diameter × 11.1 mm height) and supports conventional mercury-in-glass or digital thermometers meeting ASTM E1, ISO 17025 calibration traceability requirements. It is validated for use with NLGI Grades 000 through 6 greases, including lithium-, calcium-, aluminum-, polyurea-, and clay-thickened formulations. The instrument fulfills essential regulatory expectations for method validation under GLP (Good Laboratory Practice) environments and supports audit-ready documentation when paired with external calibrated thermometers and procedural SOPs. While not inherently 21 CFR Part 11 compliant (as it lacks electronic data capture), its mechanical design facilitates integration into fully validated QC workflows where manual recording meets internal QA specifications.
Software & Data Management
The PLD-4929A is a manually operated, analog-controlled instrument with no embedded microprocessor or digital interface. Temperature readings are obtained externally using certified reference thermometers, and results are recorded manually in laboratory notebooks or LIMS-compatible spreadsheets. For laboratories requiring electronic recordkeeping, the unit may be used in conjunction with external digital thermometers equipped with RS-232/USB output and time-stamped logging software. No proprietary firmware, cloud connectivity, or automated report generation is included—consistent with its role as a dedicated, standards-based physical testing platform.
Applications
- Quality assurance of finished lubricating greases prior to shipment (incoming/outgoing inspection)
- Formulation development and thermal stability screening during R&D
- Batch-to-batch consistency verification in OEM and additive manufacturing facilities
- Technical support for tribology studies involving high-temperature bearing applications
- Regulatory compliance testing for military specifications (e.g., MIL-PRF-10924, MIL-G-24519)
- Third-party certification testing accredited to ISO/IEC 17025
FAQ
What standards does the PLD-4929A comply with?
It is fully configured to meet GB/T 4929, ISO 2176, and ASTM D566 test requirements.
Is the instrument supplied with a thermometer?
No—users must provide a calibrated thermometer meeting ASTM E1 or ISO 17025 traceability requirements.
Can the stirring speed be adjusted?
No—the stirrer operates exclusively at 375 rpm, as specified in ASTM D566 Section 7.3.
What type of oil bath fluid is recommended?
High-thermal-stability silicone oil or mineral oil with flash point >300 °C and viscosity suitable for stable convection at 300 °C.
Does the unit include GLP audit trail functionality?
Not natively—manual recording is required; however, its mechanical repeatability supports GLP-compliant operation when paired with documented procedures and calibrated ancillary equipment.
