PAT_liquid nitrogen specifications_7.25.2026.docx

LIQUID NITROGEN (LN2) STORAGE TANK SPECIFICATION SHEET

1. Scope & Application This document outlines the core structural and performance specifications required for procuring a high-capacity, dry-vapor liquid nitrogen storage tank system of a Mid-Capacity (Class 2 / Standard Height) performance requirements. It ensures optimal biological sample preservation without direct LN2 contact, minimal evaporation loss, and long-term vacuum stability.

2. Core Technical Specifications

2.1 Thermal Performance

· Operating Phase: Isothermal dry-vapor design utilizing a jacketed liquid nitrogen reservoir incorporated directly into the wall of the freezer unit. The storage chamber must remain completely free of bulk liquid nitrogen to eliminate direct sample submersion, cross-contamination, and safety risks associated with handling liquid nitrogen.

· Thermal Uniformity: Must maintain industry-standard temperature consistency throughout the storage area, achieving an average operating temperature of -193C or lower in the dry-vapor phase with a minimal internal temperature gradient.

· Insulation Type: Multi-layer high-performance vacuum insulation jacket separating the LN2 outer jacket wall and external environment.

2.2 Structural & Material Integrity

· Constructed Material: Heavy-duty, cryogenic-grade stainless steel construction.

· Form Factor & Mobility: Compact round space-saving design mounted on heavy-duty casters for ease of mobility.

· Lid & Gasket System: Features a counter-balanced, lockable lid with an advanced woven lid gasket design to ensure a tight thermal seal and increased interior visibility during sample retrieval.

· Piping & Tubing: Features integrated annular fill and sensor tube routing.

· Access & Neck Geometry: Wide neck opening (minimum 31.0 in. /787 mm) providing unrestricted sample access and maximum internal visibility while maintaining low thermal loss.

2.3 Storage & Configuration

· System Flexibility: Accommodates all standard industry rack systems (square or rotary/carousel configurations).

· Footprint Efficiency: Must match the internal usable space of standard liquid nitrogen freezers to ensure zero loss of usable storage volume.

· Class 2 Storage Racking Capacity: Must support up to 17 standard racks holding 13 boxes per rack (total minimum capacity of 221 boxes / 22,100 vials per unit).

2.4 Safety & Monitoring

· Automated Controller & Monitoring System: Comes equipped with an integrated microprocessing auto-fill and monitoring system featuring:

· Dual-temperature display monitoring.

· Automated LN2 level sensing and auto-fill triggering.

· Programmable high/low liquid level and temperature alarm thresholds.

· Operator Safety: Complete isolation of LN2 in the jacketed perimeter wall to eliminate splashing, cold-burn risks, or sample immersion hazards during operation.

· Pressure Management: Dual relief valves with explicit Maximum Allowable Working Pressure (MAWP) ratings to safely manage LN2 jacket pressure.

3. Salient Performance Characteristics: Mid-Capacity Dry-Vapor Cryogenic Freezer (Class 2 Baseline) (The following specifications establish the minimum technical and operational thresholds for this unit class)

3.1 Volumetric & Sample Capacities

· Minimum 2 mL Vial Storage Capacity: 22,100 vials (221 boxes total across 17 racks)

· Minimum 50 mL Cryobag Capacity: 1,120 bags

· Maximum LN2 Reservoir Capacity: 75 Liters

3.2 Dimensional Constraints & Footprint

· Maximum Exterior Dimensions (W X D X H):

· Width: 37.0 in. (939 mm)

· Depth: 48.0 in. (1,219 mm)

· Height: 47.5 in. (1,206 mm)

· Minimum Usable Interior Dimensions:

· Usable Diameter: 31.0 in. (787 mm)

· Usable Height: 29.0 in. (787 mm)

· Neck Opening Diameter: 31.0 in. (787 mm)