Overview & Application

The 30m³ Underground Liquefied Petroleum Gas (LPG) Storage Tank is a stationary, subterranean, pressurized special piece of equipment. Engineered primarily for LPG storage and centralized gas supply systems, it is widely utilized in LPG distribution terminals, gasification stations, filling stations, industrial single-point gas supply systems, and centralized industrial park gas supply networks.

When searching for this specific configuration, users have already defined the volume and the underground installation method. Therefore, their core focus shifts from basic volumetric parameters to operational adaptability, valve pit and piping connection compatibility, underground anti-corrosion and anti-floating reliability, completeness of factory documentation, and the efficiency of field commissioning and acceptance. Consequently, the core value of this storage tank lies in its holistic compatibility with station processes and civil engineering, rather than just its standalone volume metric.

Process Integration & System Interconnection

Within a gas supply station process, the 30m³ underground LPG storage tank serves as the critical energy storage and pressure-stabilizing hub, primarily responsible for receiving liquid from transport tankers and maintaining stable medium storage. The equipment must seamlessly synchronize with the unloading system, liquid inlet/outlet and vapor return lines, valve pits/manifolds, downstream liquid/gas supply systems, pressure regulation and metering skids, and safety alarm interlocking systems to ensure the stable and continuous operation of the entire gas supply facility.

The operational control of the equipment revolves around four critical dimensions:

1. Optimized Piping Design: Refined layout for liquid unloading and vapor return lines to ensure smooth, stagnation-free medium transport.

2. Operational Matching: Perfect alignment between the downstream liquid/gas supply modes and the operating conditions of backend gas-consuming equipment.

3. Precision Monitoring: Accurate and stable tracking of core parameters such as liquid level and pressure.

4. Safety Compliance: Ensuring that safety accessories, such as emergency shut-off valves (ESVs) and vent/relief systems, are fully compliant and reliable.

These requirements are ultimately executed through the rational design of tank nozzle layouts, nozzle elevations, valve pit configurations, and instrument provisions, balancing operational efficiency with the ease of subsequent inspections, operations, and maintenance.

Scenario Matching & Selection Strategy

The 30m³ capacity is the mainstream standardized configuration for domestic LPG gas supply stations, catering to a vast array of scenarios. These include cylinder distribution and filling, commercial and residential centralized gas supply, industrial kiln/boiler fuel supply, thermal treatment/drying industrial heat sources, industrial park centralized networks, and emergency backup gas supply.

Since gas consumption loads, downstream processes, metering/regulation, and interlocking strategies vary significantly across different projects, the configuration of equipment nozzles, valves, and accessories cannot be universally standardized. Therefore, during the selection phase, it is vital to first clarify the station process flow and operational strategy before finalizing the nozzle and valve pit schemes. This proactive approach eliminates field modifications, schedule delays, and cost overruns at the source.

Structural Characteristics & Process Logic

This specification features a horizontal structure, which is the preferred configuration for underground LPG tanks due to its transport convenience, straightforward hoisting, mature burial technology, and highly stable operation. The equipment shell consists of a cylindrical body, dished heads, support saddles, and multi-functional nozzles. The interfaces are strictly configured based on a comprehensive process logic: “Inlet, Outlet, Return, Drain, Vent, Measure, and Inspect”. Standard interfaces include the liquid inlet, liquid/gas outlet, vapor return, vent, drain, monitoring ports, and a manway for inspection.

To adapt to underground environments, core valves, safety accessories, and instruments are centrally housed within a valve pit or riser well. This significantly enhances operational and maintenance convenience while mitigating construction and commissioning compatibility risks.

Underground Protection & Corrosion Prevention Engineering

Underground design is paramount to the long-term safe operation of the equipment, requiring simultaneous adaptation to both the medium characteristics and site-specific subsurface conditions. LPG is classified as a Category A flammable and hazardous medium, imposing stringent compliance requirements on equipment sealing, safety configurations, and explosion-proof designs. Furthermore, buried tanks endure long-term external stresses, including soil pressure, groundwater buoyancy, and surface dynamic loads. This complex operating environment demands exceptional structural protection performance.

During the engineering phase, a precise site survey must be conducted to assess soil cover depth, groundwater levels, and backfill material properties. Based on these insights, customized protection measures—such as anti-floating anchoring and foundation reinforcement—are configured. The external anti-corrosion system is tailor-made to match the soil corrosivity class and groundwater environment, ensuring the long-term integrity and reliable corrosion resistance of the protective coating. Compared to retrofitting after burial, aligning subsurface engineering parameters and optimizing protection schemes upfront yields substantial savings in construction and O&M costs while eliminating operational risks.

Construction Execution & Key Node Control

Project implementation demands seamless coordination between equipment installation and civil works into a unified construction plan. Upon site delivery, the equipment undergoes sequential inspections covering visual appearance, anti-corrosion coating integrity (spark testing), and nozzle orientation/elevation verification. It is cleared for burial only after passing all acceptance criteria.

The backfilling process strictly adheres to code standards, utilizing a layered compaction technique to prevent any damage to the anti-corrosion layer. Throughout the construction phase, focus is placed on verifying the anti-floating devices, valve pit layout, and interface maintainability. Stringent quality control is enforced at four critical milestones: Equipment Positioning, Backfill Compaction, Anti-Corrosion Re-Inspection, and Valve Pit Acceptance, ensuring a seamless project handover and successful commissioning.

Manufacturing Quality & Compliance Standards

As a pressurized special equipment, the 30m³ underground LPG storage tank is manufactured in strict accordance with national codes and industry standards. The production workflow enforces stringent quality gates on raw materials, welding quality, geometric precision, and pressure tightness. Critical pressure-retaining welds undergo mandatory non-destructive testing (NDT), followed by a comprehensive suite of factory tests, including hydrostatic and air-tightness testing, to guarantee compliant and stable performance.

Prior to dispatch, nozzle orientations, equipment markings, and accessory interfaces are verified to ensure precise alignment with the on-site piping network and valve pits. For customized projects, interface protocols, accessory brands, and data documentation delivery standards can be locked in during the ordering phase, enabling a seamless transition from manufacturing to acceptance and commissioning.

Customization & Technical Services

The equipment supports full project-specific customization. The nozzle layout can be optimized, valve pit turnkey solutions can be tailor-made, and exclusive anti-corrosion systems can be matched based on specific process requirements. Safety interlocks and remote monitoring systems can be integrated as needed, with dedicated extension interfaces reserved for emergency shut-offs, remote data acquisition (SCADA), and audio-visual alarms.

Depending on logistics and transport conditions, the equipment can be shipped as a fully assembled unit or in sections. Comprehensive technical support, including on-site installation briefings and technical guidance, is provided to help projects shorten construction timelines and achieve rapid, compliant commissioning.

Technical Specifications