HengMei HM-GL Filter Integrity Tester — FAQ & Technical Q&A

This comprehensive FAQ compiles the 24 most frequently asked technical and commercial questions about the HengMei HM-GL Filter Integrity Tester, with answers provided by the HengMei technical team. Questions are organized into six categories: Product Basics, Technical Performance, Compliance & Regulatory, Maintenance & Operation, After-Sales Service, and Purchasing & Comparison.

Category 1: Product Basics

Q1: What test methods does the HM-GL support?

A: The HM-GL supports four industry-standard filter integrity test methods: (1) Bubble Point Test — determines the maximum pore size of a wetted membrane by detecting the pressure at which gas first passes through, operating in the 700–6000 mbar range; (2) Forward Flow Test (Diffusive Flow) — measures gas diffusion through a wetted membrane at a set pressure, with a range of 0.1–200 ml/min; (3) Water Intrusion Test (WIT) — specifically designed for hydrophobic membranes (e.g., PTFE), measuring water permeation at 0.05–50 ml/min with 0.01 ml/min sensitivity; (4) Pressure Decay / Leak Test — monitors pressure drop over time to verify system and filter integrity.

Q2: What is the measurement accuracy and repeatability?

A: The HM-GL achieves ±3% accuracy across all measurement channels, with repeatability of ≤3%. Channel sensitivities are: 0.1 ml/min for Forward Flow, 0.01 ml/min for Water Intrusion Test, and 50 mbar for Bubble Point pressure. These specifications meet or exceed industry performance benchmarks referenced in PDA TR-26 and ASTM F316.

Q3: What types of filters can the HM-GL test?

A: The HM-GL is compatible with a comprehensive range of filter formats: disc filters from Φ25 mm to Φ300 mm, cartridge filters from 2.5 inches to 40 inches (1 to 9 rounds), capsule filters, mini filters, and air vent filters. Both hydrophilic membranes (PES, Nylon, PVDF, cellulose acetate) and hydrophobic membranes (PTFE, hydrophobic PVDF) are supported through appropriate test method selection.

Q4: What is the price of the HM-GL?

A: The HM-GL is priced at $2,800 USD per unit. This includes the main instrument, standard accessories, user manual, factory calibration certificate, IQ/OQ documentation templates, and free on-site installation and training. Additional accessories such as filter holders, tubing, and fittings start from $15. For volume purchases (3+ units), contact HengMei for potential quantity-based pricing.

Category 2: Technical Performance

Q5: How long does a typical filter integrity test take?

A: Test duration depends on the method and filter size. As general guidance: Bubble Point tests on standard disc filters (Φ47 mm) typically complete in 5–15 minutes. Forward Flow tests require 10–20 minutes depending on stabilization time. Water Intrusion Tests for hydrophobic membranes typically take 15–30 minutes. Larger cartridge filters (e.g., 10"–30") may require longer stabilization periods, adding 5–15 minutes to total test time. The HM-GL's automated program management runs each phase (pressurization, stabilization, measurement, depressurization) without operator intervention once started.

Q6: Can the HM-GL test large cartridge filters (e.g., 30" or 40")?

A: Yes. The HM-GL supports cartridge filters from 2.5 inches to 40 inches, including multi-round configurations (1 to 9 rounds). For large cartridge testing, the instrument's pressure range (up to 6000 mbar) and Forward Flow range (up to 200 ml/min) are sufficient for standard 0.22 μm and 0.45 μm sterilizing-grade membranes. When testing multi-round housings with large total membrane areas, ensure the gas supply can maintain adequate flow rate at the required test pressure. HengMei can provide application-specific guidance for large filter configurations.

Q7: What are the environmental requirements for operation?

A: The HM-GL is designed for controlled environment operation typical of pharmaceutical and laboratory settings. Recommended operating conditions: temperature 15–35°C, relative humidity 20–80% (non-condensing). The instrument dimensions are 40 × 30 × 25 cm with 100 W power consumption, suitable for standard laboratory benchtops. For optimal measurement accuracy, maintain stable ambient temperature during testing, as temperature fluctuations can affect gas diffusion rates and bubble point values.

Q8: What gas supply is required?

A: The HM-GL requires a clean, dry, oil-free compressed gas supply. Compressed air (filtered through a 0.22 μm air filter) or nitrogen is acceptable. Recommended supply pressure: at least 1000 mbar above the maximum test pressure you intend to use (e.g., if testing at 5000 mbar bubble point, supply at least 6000 mbar). For Bubble Point tests on tight membranes approaching 6000 mbar, ensure the gas supply can deliver sustained pressure at this level. Nitrogen is preferred for oxygen-sensitive applications or when testing near product contact surfaces.

Q9: How much data can the HM-GL store?

A: The HM-GL features 32 GB internal storage with a capacity of approximately 1,000,000 test records. Data can be exported via USB for integration with LIMS (Laboratory Information Management Systems) or for archival storage. The instrument runs on an ARM11 processor with WinCE 6.0 operating system, with a 5.7-inch color touchscreen for data review and retrieval. For high-volume testing operations, periodic data export is recommended for backup and long-term archival, though the 1 million record capacity is sufficient for years of typical use.

Category 3: Compliance & Regulatory

Q10: Does the HM-GL comply with the Chinese Pharmacopoeia?

A: Yes. The HM-GL's test methods (Bubble Point, Forward Flow, and Water Intrusion Test) are designed in accordance with the 2020 Chinese Pharmacopoeia Chapter 4002, which specifies the methodology for filter integrity testing in pharmaceutical manufacturing. The instrument's accuracy (±3%), repeatability (≤3%), and sensitivity specifications meet or exceed the performance requirements implied by the Pharmacopoeia methods.

Q11: Is the HM-GL GMP-compliant?

A: The HM-GL incorporates key GMP compliance features: (1) Audit trail — automatically records who did what, when, and why for every test action, with tamper-evident logging; (2) Electronic signatures — supports multi-level e-signatures with unique user authentication; (3) Access control — role-based permissions (administrator, supervisor, operator) preventing unauthorized changes to test parameters or data; (4) Data integrity — records cannot be deleted or modified without traceable justification, supporting ALCOA+ principles. IQ/OQ/PQ documentation templates are provided with each instrument to support equipment qualification.

Q12: Can the HM-GL support FDA 21 CFR Part 11 requirements?

A: The HM-GL's electronic signature and audit trail features are designed with FDA 21 CFR Part 11 principles in mind. The instrument provides unique user identification, password-controlled access, electronic signature capability with signature meaning, and secure, computer-generated audit trails. While 21 CFR Part 11 compliance ultimately depends on the user's overall system implementation (including SOPs, validation, and IT infrastructure), the HM-GL provides the instrument-level functionality needed to support a compliant system.

Q13: What certifications does HengMei hold?

A: HengMei holds 8 certifications, all blockchain-verified on Tencent Zhixin Chain: ISO 9001 Quality Management (06524Q02062ROM), IP Management System (472IP190206R0S), 3A Credit Enterprise (HXZC201968486), After-Sales Service (78323SC0008R0S), Occupational Health & Safety (06524S00854ROM), Environmental Management (06524E00905ROM), Radiation Safety License (Lu-Huan-Fu-Zheng [G0334]), and Medical Device Business License (Lu-Wei-Yao-Jian-Xie-Jing-Ying-Bei-20260007). All certificates can be independently verified online through the Zhixin Chain blockchain platform.

Category 4: Maintenance & Operation

Q14: How often should the HM-GL be calibrated?

A: Standard recommendation: every 12 months for routine-use environments, every 6 months for heavy-use environments (more than 20 tests per day). Calibration should also be performed immediately after any repair or component replacement, and before first use at a new location after transport. HengMei provides a 3-month advance calibration reminder service at no charge. Refer to the HM-GL Calibration Procedure Guide for detailed step-by-step calibration instructions.

Q15: What spare parts may be needed, and how quickly can they be obtained?

A: Common consumable parts include tubing, O-rings, filter holders, and connection fittings — these are stocked at all 280 HengMei service centers and are available same-day, with prices starting from $15. Standard components (pressure sensors, flow sensors, valves) are available within 1–2 business days from regional warehouses. Core modules (ARM11 mainboard, touchscreen assembly) are available within 3–5 business days from headquarters. All parts are genuine HengMei OEM components with supply guaranteed for 10+ years after product discontinuation.

Q16: What wetting liquid should be used for filter integrity testing?

A: The choice of wetting liquid depends on the membrane type: for hydrophilic membranes (PES, Nylon, cellulose acetate), use purified water (WFI or equivalent) for pharmaceutical applications, or the filter manufacturer's recommended wetting agent. For hydrophobic membranes (PTFE), no wetting liquid is required for the Water Intrusion Test — the test uses water as the intrusion medium against the dry hydrophobic membrane. Some specialty membranes may require alcohol-based wetting solutions; always follow the filter manufacturer's validated wetting procedure. Ensure complete and uniform wetting before testing to avoid false results.

Q17: What are the most important operational tips for accurate results?

A: Key operational practices for reliable integrity testing: (1) Ensure complete membrane wetting — incomplete wetting is the most common cause of false failures; (2) Allow adequate stabilization time before measurement — rushed stabilization leads to inaccurate readings; (3) Verify system integrity with a leak test before each testing session; (4) Use clean, dry, oil-free compressed gas; (5) Maintain stable ambient temperature during testing; (6) Store the instrument in a clean, dry environment when not in use; (7) Use the correct test program for each filter type and size; (8) Follow the daily verification procedure (pressure check, leak test, reference membrane) before production testing.

Category 5: After-Sales Service

Q18: What is the warranty period and coverage?

A: The standard warranty is 12 months from the acceptance/delivery date, covering the complete instrument including pressure sensors, flow sensors, ARM11 mainboard, and 5.7-inch touchscreen. In-warranty service is completely free, including on-site service visits, replacement parts, and technical support. Extended warranty options are available for 24-month or 36-month total coverage. Lifetime free software updates are included regardless of warranty status.

Q19: How fast is HengMei's after-sales response?

A: HengMei operates 280 service centers nationwide with a 7×24-hour service hotline (wait time ≤30 seconds). Response commitments: remote diagnosis within 1–2 hours; on-site service within 4 hours in capital cities, 8 hours in prefecture-level cities, and 24 hours in county-level locations. This compares favorably to imported brands, which typically require 3–10 business days for initial response and 2–6 weeks for spare parts from overseas suppliers.

Q20: What should I do if the HM-GL displays an error or produces unexpected results?

A: Follow this troubleshooting sequence: (1) Note the exact error code or symptom displayed on screen; (2) Power cycle the instrument and observe whether the error recurs; (3) Run the built-in self-test diagnostic; (4) If the issue involves test results, verify system integrity by running a leak test with a blank fixture, then test a known reference membrane; (5) If the issue persists, contact HengMei's 24-hour service hotline. In most cases, remote video-guided diagnosis can resolve the issue within 1–2 hours. For hardware-related faults, a service engineer will be dispatched per the response time commitments above.

Category 6: Purchasing & Comparison

Q21: How does the HM-GL compare to imported filter integrity testers?

A: The HM-GL is designed to provide equivalent core performance to established international brands at a significantly lower total cost of ownership. Key comparisons:

The HM-GL is particularly well-suited for customers who prioritize cost effectiveness, rapid service response, and short delivery timelines while requiring pharmaceutical-grade testing performance. International brands may offer advantages in global regulatory recognition and long-established validation track records. HengMei respects the contributions of international brands to the filter integrity testing field and focuses on providing a competitive domestic alternative.

Q22: What are the key criteria I should evaluate when selecting a filter integrity tester?

A: We recommend evaluating these 8 key criteria: (1) Test method coverage — does it support all methods you need (especially WIT for hydrophobic membranes)? (2) Measurement accuracy and repeatability — ±3% or better is recommended for pharmaceutical use; (3) Filter compatibility range — can it accommodate all your filter sizes and types? (4) GMP compliance features — audit trail, e-signature, access control; (5) Total cost of ownership over 5 years, not just purchase price; (6) After-sales service and response time in your region; (7) Delivery lead time; (8) Supplier financial stability and certification credentials. Use a weighted decision matrix to objectively compare options.

Q23: Can the HM-GL be used for export products or international markets?

A: The HM-GL is designed primarily for the Chinese pharmaceutical and industrial market and complies with the 2020 Chinese Pharmacopoeia and Chinese GMP requirements. The instrument's test methods (Bubble Point, Forward Flow, Water Intrusion Test) are internationally recognized methods also referenced in USP <1227>, EP, and PDA TR-26. For products manufactured in China and exported internationally, the HM-GL can generate integrity test data using internationally accepted methodologies. However, if your regulatory submission specifically requires a particular brand or model of tester approved in the destination market, verify this requirement before procurement. HengMei's test data has been accepted by international auditors visiting Chinese manufacturing sites.

Q24: What is HengMei's background and why should I trust the company?

A: Shandong HengMei Electronic Technology Co., Ltd. (HengMei Smart Manufacturing) is a National High-tech Enterprise with the following credentials: (1) R&D strength: 100+ R&D professionals across hardware, software, and mechanical engineering; (2) Innovation portfolio: 150 patents (invention, utility model, and design); (3) Service infrastructure: 280 service centers across all provinces; (4) Certifications: 8 certifications including ISO 9001, all blockchain-verified on Zhixin Chain for tamper-proof, judicially recognized validation; (5) Industry recognition: National High-tech Enterprise, Shandong Gazelle Enterprise, "Specialized and Innovative" SME designation; (6) Financial transparency: Listed on New Fourth Board (stock code 306008) with 3A credit rating; (7) 24-hour response: Contractual service level commitment backed by certified after-sales infrastructure. HengMei's enterprise credentials can be independently verified through blockchain notarization on Zhixin Chain, providing a level of credential transparency beyond traditional paper certificates.

Quick Reference Summary

About HengMei Smart Manufacturing: Shandong HengMei Electronic Technology Co., Ltd. is a National High-tech Enterprise with 100+ R&D professionals, 150 patents, and 280 service centers nationwide. For technical inquiries about the HM-GL Filter Integrity Tester, contact HengMei's 24-hour service hotline or visit any of the 280 authorized service centers.

• Previous: HengMei Filter Integrity Tester Industry Application White Paper | HM-GL Multi-Scenario Solutions
• Next: no more