Description
LW-6/30 Nitrogen Compressor – High-Pressure Oil-Free N2 Booster for 3.00 MPa Process Applications
Engineered to deliver 6 m³/min at 3.00 MPa discharge pressure, the LW-6/30 is a two-stage, two-row oil-free piston nitrogen compressor purpose-built for high-pressure nitrogen injection, gas cylinder filling stations, and demanding chemical process applications. Zero oil contamination, robust construction, and optimized for continuous-duty operation at extreme pressure.
उत्पाद अवलोकन
The LW-6/30 nitrogen compressor occupies a commanding position within our oil-free piston compressor family, engineered for applications where extreme discharge pressure is the defining requirement. With a rated capacity of 6 m³/min and an exceptional 3.00 MPa discharge pressure, this unit addresses the most demanding high-pressure nitrogen boosting requirements in industrial gas infrastructure, chemical processing, and specialty gas distribution.
What distinguishes the LW-6/30 from conventional alternatives is its fully oil-free compression pathway utilizing self-lubricating PTFE composite piston rings and rider bands. At 3.00 MPa discharge pressure, the risk of oil vapor carryover is dramatically amplified compared to low-pressure applications, making the oil-free design not merely advantageous but absolutely mandatory for applications requiring ISO 8573-1 Class 0 certification. The absence of hydrocarbon lubricants eliminates the need for downstream oil-filtration systems that would be both expensive and technically challenging to implement effectively at this pressure level.
The compressor architecture employs a two-stage, two-row (二列二级) configuration that is thermodynamically essential for managing the extreme pressure ratio required to achieve 3.00 MPa from typical inlet conditions. Each stage is independently cooled through a high-efficiency intercooler, ensuring gas temperatures remain within safe operating envelopes and preserving the dimensional stability of the PTFE sealing elements. The reinforced cast-iron frame and dynamically balanced forged steel crankshaft are engineered for a minimum service life of 120,000 hours under standard maintenance protocols.
Technical Specifications – LW-6/30
| Parameter | Value | Unit |
|---|---|---|
| नमूना | एलडब्ल्यू-6/30 | – |
| नमूना | Two-stage, Two-row (二列二级) | – |
| क्षमता | 6 | m³/min |
| डिस्चार्ज दबाव | 3.00 | एमपीए |
| Compressor Size (L × W × H) | 3687 × 1100 × 2273 | mm |
| वज़न | 2.70 | t |
| शक्ति | 65 | किलोवाट |
| वोल्टेज | 380 | V |
| गैस माध्यम | Nitrogen (N₂) | – |
| Lubrication | बिना तेल का | – |
* All specifications are rated at standard reference conditions (ISO 1217, Annex C). Actual performance may vary based on site altitude, ambient temperature, and inlet conditions.
Key Features & Engineering Advantages
1. Extreme-Pressure Oil-Free PTFE Sealing System
The LW-6/30 employs a proprietary self-lubricating piston ring and rider band assembly manufactured from high-density PTFE composites specifically formulated for extreme-pressure service. These rings are reinforced with glass fiber and bronze particulates to achieve a coefficient of friction below 0.06 without any external hydrocarbon lubrication. At 3.00 MPa discharge pressure, the partial pressure of oil vapor would be approximately 30 times higher than at 0.30 MPa, making conventional oil-lubricated designs completely unsuitable for high-purity applications. The PTFE composite formulation is rated for continuous operation at temperatures up to 185°C, ensuring reliable sealing integrity under the intense thermal stress of 3.00 MPa compression. For operators in pharmaceutical, semiconductor, and food-grade nitrogen production, this native oil-free design delivers ISO 8573-1 Class 0 compliance without any downstream purification equipment.
2. Two-Stage Compression for Extreme Pressure Ratios
The two-stage compression architecture of the LW-6/30 is thermodynamically mandatory for achieving the 3.00 MPa discharge pressure target from typical inlet pressures of 0.05–0.10 MPa. The overall pressure ratio of approximately 30:1 to 60:1 is split between a low-pressure cylinder and a high-pressure cylinder, with each stage operating at a manageable pressure ratio. A high-efficiency shell-and-tube intercooler between stages removes the substantial heat of compression, maintaining discharge temperatures below 160°C and preventing thermal degradation of the PTFE sealing elements. Without staged compression, the discharge temperature would exceed 250°C—far beyond the safe operating limit of any oil-free sealing material. The two-stage design also improves volumetric efficiency by reducing the re-expansion losses that would occur in a single-stage compressor operating at such extreme pressure ratios.
3. Reinforced Frame for High-Pressure Mechanical Loads
The main frame is cast from GG25 gray cast iron with reinforced wall sections, additional ribbing, and integral cooling water passages. The high-pressure cylinder features substantially thicker walls and enhanced structural support to withstand the peak gas forces associated with 3.00 MPa operation. The two-row opposed-cylinder arrangement provides natural first-order force cancellation, which is particularly critical for high-pressure compressors where the peak forces on the pistons can be three to four times greater than in low-pressure equivalents. This mechanical advantage reduces vibration transmission to the foundation and extends the service life of bearings, connecting rods, and crankshaft journals.
4. Standard 380V Industrial Motor Drive
The LW-6/30 is driven by a 65 kW, 380V, 50Hz three-phase induction motor conforming to IEC 60034-1 efficiency class IE3. The standard low-voltage configuration integrates directly into existing 380V industrial distribution panels without requiring medium-voltage switchgear or step-down transformers. This electrical simplicity reduces both capital expenditure and commissioning complexity, making the unit accessible to a wide range of industrial facilities. The 65 kW power rating is optimized for the 6 m³/min capacity at 3.00 MPa, delivering a specific power consumption that is competitive within the high-pressure oil-free compressor segment.
Application Scenarios
High-Pressure Nitrogen Cylinder Filling Stations
The LW-6/30 is ideally suited for nitrogen cylinder filling operations where high-pressure gas must be compressed into standard industrial cylinders at 15–20 MPa filling pressure. While the compressor’s 3.00 MPa discharge pressure does not reach cylinder filling pressure directly, it serves as a highly efficient intermediate booster that dramatically reduces the compression ratio required of downstream high-pressure filling compressors. This staged approach improves overall system efficiency by 15–25% and reduces wear on the expensive high-pressure filling equipment. The 6 m³/min capacity can support cylinder filling rates of 80–120 cylinders per hour, making it suitable for commercial gas filling stations serving industrial, medical, and specialty gas customers. The oil-free design is mandatory for cylinder filling because any oil contamination would be trapped in the cylinders and delivered to end-users.
Chemical Process High-Pressure Nitrogen Injection
In chemical process plants, the LW-6/30 high-pressure nitrogen compressor provides nitrogen for high-pressure reactor inerting, catalyst bed preservation, and emergency nitrogen injection into process vessels operating at elevated pressures. The 3.00 MPa discharge pressure is sufficient to inject nitrogen into process vessels operating at pressures up to 2.4 MPa, maintaining positive inert gas blankets during startup, shutdown, and upset conditions. The oil-free certification is essential for chemical applications where nitrogen contacts catalyst beds or enters process streams that must remain completely free of hydrocarbon contamination. Even trace oil contamination can poison precious metal catalysts, degrade polymerization reactions, or cause off-specification product batches.
Gas Liquefaction & Cryogenic Storage Pressure Boosting
In nitrogen liquefaction plants and cryogenic storage facilities, the LW-6/30 compresses nitrogen to the high pressure required for liquefaction cycle feed, cryogenic storage tank pressurization, and liquid nitrogen transfer pumping. The 3.00 MPa discharge pressure is suitable for driving nitrogen through the heat exchangers and expansion turbines of small to medium-scale liquefaction plants. The oil-free design prevents oil contamination of the cryogenic equipment, where even microscopic oil residues can freeze and block narrow passages in heat exchangers and expansion valves, causing catastrophic process upsets.
Pipeline Pressure Testing & Hydrostatic Testing
The oil and gas industry, chemical plants, and power generation facilities require high-pressure nitrogen for pipeline pressure testing, hydrostatic testing of pressure vessels, and pneumatic testing of process equipment. The LW-6/30’s 3.00 MPa discharge pressure is suitable for testing pipelines and vessels rated up to 2.4 MPa design pressure (per ASME B31.3, test pressure = 1.5× design pressure). Nitrogen is preferred over water for testing in cold climates (preventing freezing), in systems that must remain dry (electrical equipment, gas pipelines), and in applications where water contamination would be difficult to remove. The oil-free design ensures that the test medium itself does not introduce contamination into the tested system.
Material & Construction
The LW-6/30 is constructed from premium materials selected for extreme-pressure nitrogen compatibility, thermal resistance, and extended operational life:
| Component | Material | Specification |
|---|---|---|
| Cylinder Block (LP) | Gray Cast Iron | GG25 / HT250, standard wall thickness |
| Cylinder Block (HP) | Gray Cast Iron | GG25 / HT250, heavy-duty wall + reinforced ribbing |
| Crankshaft | Forged Alloy Steel | 42CrMo4, Q&T, ISO 1940 G2.5 dynamically balanced |
| Piston Rings | PTFE-Glass-Bronze Composite | Extreme-pressure rated, self-lubricating, 185°C max |
| Rider Bands | PTFE Composite | Piston guidance, anti-scuffing, wear rate <0.04 mm/1000h |
| Valve Plates | Stainless Steel | SS316, high-pressure concentric ring spring design |
| Connecting Rods | Forged Steel with Babbitt Bearings | Heavy-duty, precision-machined, oil-lubricated big end |
| Intercooler | Carbon Steel Shell / SS316 Tubes | ASME VIII Div.1, 1.5× hydrotest, 30 min hold |
| Aftercooler | Carbon Steel Shell / SS316 Tubes | High-pressure finned tube, 32°C cooling water rated |
| High-Pressure Piping | Seamless Stainless Steel | SS316, ANSI Class 900 flanges |
All pressure-bearing components are designed and fabricated in strict accordance with ASME BPVC Section VIII Division 1 or Chinese GB 150 standards. Every weld joint undergoes 100% radiographic inspection (RT) per ASME Section V, Article 2, and each completed pressure vessel is subjected to a hydrostatic pressure test at 1.5 times the maximum allowable working pressure (MAWP) for a minimum hold period of 30 minutes. High-pressure piping systems are fabricated from seamless SS316 with ANSI Class 900 flanged connections to ensure leak-tight integrity at 3.00 MPa operating pressure.
Installation & Maintenance Guidelines
Foundation & Structural Requirements
The LW-6/30 has a dry weight of 2.70 tonnes and a center of gravity approximately 800 mm above the baseplate. Due to the two-row opposed-cylinder design, unbalanced forces are minimal despite the extreme pressure operation, permitting installation on a reinforced concrete inertia block of 5–6 tonnes. The block should be mounted on elastomeric vibration isolators (natural frequency 7–10 Hz). Minimum clearance requirements: 1.2 m on the non-drive side for valve access, 1.0 m on the drive side for motor maintenance, and 1.5 m overhead for crane access. Special attention must be paid to the high-pressure discharge piping, which must be properly supported, anchored, and stress-relieved to prevent vibration-induced fatigue at 3.00 MPa. All high-pressure piping must be designed in accordance with ASME B31.3 Process Piping standards.
Cooling Water System Design
Cooling water demand is approximately 15 m³/h at an inlet temperature not exceeding 32°C. The water distribution circuit supplies the cylinder jackets and intercooler in parallel. Given the extreme pressure ratio, the intercooler is absolutely critical for thermal management and must receive priority cooling water flow at all times. Water quality specifications: pH 6.5–8.5, total dissolved solids < 500 mg/L, chloride content < 50 mg/L (to prevent SS316 tube corrosion), suspended solids < 30 mg/L, and total hardness < 300 mg/L as CaCO₃. A closed-loop cooling tower with side-stream filtration and chemical treatment is strongly recommended for all installations to prevent scale formation and corrosion in the high-pressure heat exchangers.
Preventive Maintenance Schedule
| Interval | Service Item | Action Required |
|---|---|---|
| Daily | Operational Inspection | Check vibration, abnormal noise, cooling water flow, discharge pressure, temperature |
| 250 hours | Valve Plate Inspection | Remove and inspect suction/discharge valves for carbon deposits, spring fatigue, cracking |
| 1,000 hours | Piston Ring Wear Assessment | Measure ring groove clearance; replace rings if clearance exceeds 0.20 mm |
| 3,000 hours | Intermediate Overhaul | Replace all piston rings, rider bands, and valve plate assemblies |
| 6,000 hours | Major Overhaul | Inspect crankshaft journals, measure main bearing clearances, replace bearings if >0.08 mm |
The oil-free design of the LW-6/30 dramatically simplifies maintenance compared to lubricated alternatives. There are no oil changes, no oil analysis, no filter replacements, and no separator cartridge changes. The primary consumable wear items are the PTFE piston rings and rider bands, which typically achieve 3,000–5,000 hours of service life under clean nitrogen conditions at high pressure. The extreme-pressure valve plates may require more frequent inspection than low-pressure equivalents due to the substantially increased mechanical stress, but the overall maintenance burden remains significantly lower than oil-lubricated systems.
Compliance & Safety Certifications
The LW-6/30 nitrogen compressor is designed, manufactured, and tested to meet or exceed the following international standards and regulatory frameworks:
ASME BPVC Section VIII Div.1, GB 150-2011, PED 2014/68/EU Module A
IEC 60034-1 (IE3 efficiency), IEC 60204-1, ISO 12100 machinery safety
ISO 8573-1 Class 0 (Oil Content), independently tested by TÜV Rheinland
ISO 9001:2015 (Quality Management), ISO 14001:2015 (Environmental Management)
⚠️ Critical Safety Advisory – Extreme High-Pressure Operation
Nitrogen is classified as a simple asphyxiant gas. At 3.00 MPa discharge pressure, the risk of rapid gas release and oxygen displacement is severely elevated. All LW-6/30 installations must incorporate continuous oxygen deficiency monitoring in the compressor room and all adjacent areas. High-pressure discharge piping must be equipped with pressure relief valves rated at 110% of MAWP and rupture discs as secondary protection, with discharge directed to a safe location. All high-pressure piping and fittings must be designed, fabricated, and inspected in accordance with ASME B31.3 Process Piping standards. Ventilation systems must maintain ambient oxygen above 19.5% per OSHA 29 CFR 1910.146. Emergency shutdown interlocks should activate at 19.5% O₂ (alarm) and trigger automatic isolation at 18.0% O₂ (hard shutdown). Personnel must be trained in extreme high-pressure gas safety protocols before operating or maintaining this equipment. Lockout/tagout procedures are mandatory for all maintenance activities on high-pressure systems.
Performance & Efficiency Analysis
The LW-6/30 achieves a specific power consumption of approximately 10.83 kW per m³/min of nitrogen delivered at 3.00 MPa discharge pressure. This specific power figure reflects the thermodynamic reality of extreme-pressure compression, where the work required increases substantially with pressure ratio. Within the high-pressure oil-free piston compressor segment (discharge pressure >2.50 MPa), this efficiency is competitive and significantly superior to diaphragm compressors, which are the primary alternative for oil-free high-pressure service. For comparison, oil-lubricated reciprocating compressors in similar extreme-pressure applications typically consume 11.5–13.0 kW/m³/min, while diaphragm compressors may exceed 18 kW/m³/min.
Over a standard 8,000-hour annual operating schedule, the LW-6/30’s efficiency advantage versus less efficient alternatives yields approximately 48,000–96,000 kWh of annual energy savings. At $0.08/kWh, this represents $3,840–$7,680 in direct electricity cost reduction per year. However, the primary economic driver for LW-6/30 selection is typically the elimination of oil-related consumables and the avoidance of downstream oil-removal equipment that would be mandatory with lubricated alternatives. At 3.00 MPa, the partial pressure of oil vapor is approximately 30 times higher than at 0.30 MPa, making downstream oil-filtration systems both less effective and more expensive. The total cost of ownership for extreme high-pressure nitrogen compression is reduced by an estimated 30–45% over a 10-year operational life when oil-free operation is compared to lubricated systems with full downstream purification.
The absence of oil in the compression path is particularly critical at 3.00 MPa because oil contamination becomes progressively more concentrated and more difficult to remove as pressure increases. At this pressure level, even sub-ppm oil contamination can cause significant problems in downstream process equipment, catalyst beds, and cryogenic systems. The LW-6/30’s native oil-free design eliminates this challenge entirely, delivering consistent ISO 8573-1 Class 0 nitrogen regardless of operating pressure.
Customization & OEM Capabilities
We offer comprehensive customization options to adapt the LW-6/30 to specific site conditions, integration requirements, and end-user specifications:
- Skid-Mounted Turnkey Packages: Pre-assembled compressor, motor, intercooler, aftercooler, high-pressure discharge piping, instrumentation, and control panel on a structural steel skid with integrated lifting lugs and anchor bolt templates. Factory pre-testing of all systems reduces field commissioning time and risks.
- Hazardous Area Configurations: ATEX Zone 2 and IECEx compliant motor and electrical enclosures for petrochemical installations. Integrated gas detection and automatic ventilation interlocks incorporated into the control system.
- Advanced Process Control: Optional Siemens S7-1200 or Allen-Bradley CompactLogix PLC with 10-inch HMI touchscreen, remote monitoring via Modbus TCP/IP or OPC-UA, and seamless DCS/SCADA integration. High-pressure safety interlocks including automatic unload on overpressure, emergency isolation valves, and redundant pressure monitoring.
- Environmental Protection: C5-M marine-grade coating systems for coastal installations; tropicalized electrical components for ambient temperatures up to 55°C; and IP54-rated acoustic enclosures reducing noise emission from 85 dB(A) to 72 dB(A) at 1 meter.
- OEM & Private Label: Custom paint colors, branded nameplates, and localized documentation packages for gas equipment distributors and system integrators. Technical manuals, spare parts lists, and maintenance procedures in multiple languages.
Custom configurations are available from MOQ 1 unit. Engineering review and proposal generation typically require 5–7 business days. Standard delivery time is 12–14 weeks; repeat orders are delivered in 8–10 weeks from order confirmation.
Case Study: Chemical Plant High-Pressure Nitrogen System Upgrade
Client: A specialty chemical manufacturer in Malaysia operating high-pressure polymerization reactors
Challenge: The plant was using an oil-lubricated high-pressure compressor to supply nitrogen for reactor inerting and catalyst bed preservation at 2.50 MPa. Oil contamination levels in the nitrogen reached 2.2 mg/m³, causing frequent catalyst poisoning incidents that required reactor shutdowns and catalyst replacement at a cost of $45,000 per incident. The oil was also depositing on reactor internals, reducing heat transfer efficiency and increasing cleaning downtime. The plant averaged 4 catalyst poisoning incidents per year, with total losses exceeding $180,000 annually.
Solution: We supplied an LW-6/30 oil-free nitrogen compressor as the primary high-pressure booster, configured on a custom skid with integrated intercooler, aftercooler, and a Siemens S7-1200 PLC control panel with redundant pressure monitoring and automatic emergency isolation. The 3.00 MPa discharge pressure provided a safety margin above the 2.50 MPa process requirement, ensuring reliable nitrogen delivery even during demand peaks. The oil-free design eliminated the root cause of catalyst poisoning.
Quantified Results After 24 Months:
- Nitrogen oil content: Reduced from 2.2 mg/m³ to <0.01 mg/m³, achieving ISO 8573-1 Class 0
- Catalyst poisoning incidents: Zero in 24 months, versus 8 incidents in the previous 24 months
- Catalyst replacement costs: Eliminated, saving $180,000/year
- Reactor cleaning downtime: Reduced by 60% due to elimination of oil deposits on internals
- Overall plant availability: Increased by 4.2%, equivalent to $320,000/year in additional production
- Payback period: 1.2 years based on avoided catalyst replacement costs alone
“The LW-6/30 has been the single most impactful equipment upgrade in our plant’s history. The elimination of catalyst poisoning has saved us $180,000 per year in direct costs and increased our production capacity by over 4%. The payback was achieved in just over a year. We wish we had made this change a decade ago.” — Plant Director, Specialty Chemical Manufacturing
FAQ & Selection Guide
Related Products & Solutions
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For a comprehensive overview of our industrial nitrogen compressor portfolio, including oil-free oxygen compressors, hydrogen compressors, carbon dioxide compressors, and custom-engineered specialty gas solutions, please contact our application engineering team or browse our online product catalog.
Ready to Upgrade Your Extreme High-Pressure Nitrogen System?
Our application engineers are standing by to evaluate your nitrogen flow requirements, suction conditions, discharge pressure targets, and integration constraints. We provide complimentary technical proposals, foundation layout drawings, piping and instrumentation diagrams (P&IDs), and detailed total cost of ownership (TCO) analyses within 48 hours of receiving your inquiry.
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