AVET Series / Hydrostatic Cylinder Testing / ISO 6406 · IS 8451 / Noida · India

AVET · 1.5× WORKING PRESSURE

Automatic Volumetric Expansion Test System, precision hydrostatic testing at 1.5× working pressure.

The AVET fills a high-pressure gas cylinder with water, pressurizes it to 1.5 times its working pressure, and automatically measures elastic and permanent volumetric expansion — the definitive test for whether a CNG, Oxygen, Hydrogen, Nitrogen, CO2, Argon, or SCBA cylinder remains safe for continued service or must be scrapped.

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Automatic Volumetric Expansion Test System — control panel cabinet with dual pressure gauges and instrumentation rack, Neometrix hydrostatic cylinder test machine

Fig · 01 Installed configuration — control & pump cabinet with dual pressure gauges and instrumentation rack

Testing performed in compliance with:

ISO 6406 EN 1968 ASME BPVC · VIII IS 8451

Test Pressure

1.5×WORKING P.

Pass / Fail Limit

10% PERM. EXP.

Cylinder Types

7GAS CLASSES

Frame

SSSTAINLESS

Standards

6+ISO/EN/ASME/IS

Overview

10% permanent expansion is the line between safe and scrap.

Hydrostatic testing is the most reliable and widely accepted method for verifying the strength and expansion characteristics of gas cylinders under high pressure. This automatic volumetric test system exists to make that determination automatically, repeatably, and safely — every time.

Automatic Volumetric Expansion Test System — control cabinet with pressure gauges beside instrumentation rack, outdoor industrial installation by Neometrix

Fig · 02 Control & pump cabinet with instrumentation rack — site installation

The AVET is a high-precision hydrostatic testing solution designed to assess the structural integrity and safety of high-pressure gas cylinders used across automotive, industrial gas storage, medical, aerospace, and defence applications. It operates by filling the cylinder with water, pressurizing it to 1.5 times its working pressure, and measuring elastic and permanent expansion to determine its usability.

Cylinders tested to the ISO 6406 permanent expansion criterion, with permanent expansion of 10% or less, are deemed safe. Those exceeding this threshold are scrapped for safety reasons.

The system features automated data acquisition, customizable pressure settings, and a self-lubricating pump system, ensuring high accuracy, operational efficiency, and minimal maintenance. With a robust stainless steel frame and advanced safety mechanisms, it supports a wide range of gas cylinders, including CNG, Oxygen, Hydrogen, Nitrogen, CO2, Argon, and SCBA cylinders — fully compliant with global safety standards.

Working Principle

One formula. Zero ambiguity.

The Automatic Volumetric Expansion Test System operates using the hydrostatic expansion testing method, where a gas cylinder is filled with water and subjected to high pressure. This test identifies leaks, deformities, or structural weaknesses before a cylinder is refilled with gas.

Expansion Measurement Formula

The percentage of permanent expansion is calculated using the formula:

% Permanent Expansion = [(A − C) / (A − B)] × 100

A = Initial water volume inside the cylinder
B = Water volume when the cylinder is pressurized
C = Final water volume after releasing the pressure

Pass / Fail Criteria & Test Pressure

If permanent expansion is 10% or less, the cylinder is approved for further use.
If permanent expansion exceeds 10%, the cylinder fails the test and must be scrapped for safety reasons.
Per Government of India (GOI) Cylinder Rules, the test pressure of every cylinder must be 1.5 times its working pressure.
This ensures the cylinder can withstand extreme conditions beyond normal operating pressure, significantly reducing risks of leaks, explosions, and catastrophic failures.

Key Features

Built for accuracy, built for uptime.

Every subsystem is designed to remove operator variability from the test result while keeping the machine safe to run in a working test bay.

Feature · 01

Precise Expansion Measurement

Uses hydrostatic expansion testing to measure elastic and permanent expansion of high-pressure gas cylinders precisely.

Feature · 02

Automatic Pass / Fail

Applies 1.5× working pressure as test pressure; cylinders with over 10% permanent expansion are automatically failed.

Feature · 03

Wide Cylinder Coverage

Tests CNG, Oxygen, Hydrogen, Nitrogen, CO2, Argon, and SCBA cylinders in both metal and composite construction types.

Feature · 04

Inherently Safe Design

Generates no heat, flame, or sparks; fully enclosed operator-safe housing eliminates fire and explosion hazards.

Feature · 05

Automated Data Acquisition

Minimizes human errors, ensuring consistent and reliable expansion measurement results across every test cycle.

Feature · 06

Self-Lubricating Pump

Needs no external air-line lubrication, reducing maintenance and ensuring long-term durability of the pump system.

Feature · 07

Stainless Steel Frame

Provides corrosion resistance and a compact footprint for easy installation in industrial test facilities.

Feature · 08

Variable Cycling Speed

Infinitely variable cycling speed customizes flow rate without adverse effects from continuous stop/start operations.

Gallery

Product views.

Installed and workshop photography of the Automatic Volumetric Expansion Test System control cabinet, instrumentation rack, and internal manifold assembly.

AVET control cabinet and instrumentation rack in factory floor

AVET control cabinet with pressure gauges, outdoor installation

AVET instrumentation rack, outdoor site view with palm trees

AVET control cabinet and rack, angled warehouse view

AVET internal manifold assembly with pressure transducers, open cabinet interior

AVET control cabinet and instrumentation rack, outdoor shed

AVET control cabinet and instrumentation rack, composite render view

AVET internal manifold and solenoid valve assembly, open cabinet close-up

Applications

Where cylinder integrity cannot be assumed.

01Gas cylinder testing & requalification / certification facilities

02Industrial gas storage & distribution — Oxygen, Nitrogen, Hydrogen, CO2, Argon, Helium

03Automotive & transportation — periodic testing of CNG and Hydrogen fuel cylinders

04Petroleum, oil & gas — high-pressure storage cylinders in refineries and gas transport

05Aerospace & defence — Oxygen and Nitrogen cylinders used in military aircraft and spacecraft

06Medical & healthcare facilities — hospital oxygen cylinder safety compliance

07Firefighting & safety equipment — SCBA cylinder testing for firefighters and rescue teams

Compliance

Every tested cylinder, audit-ready.

The AVET is engineered to meet global safety standards, ensuring that every tested cylinder complies with international quality and safety benchmarks.

ISO 6406	Periodic Inspection & Testing of Gas Cylinders
EN 1968	European Standard for High-Pressure Cylinder Testing
DOT CFR-49	US Department of Transportation Gas Cylinder Regulations
ASME BPVC — Section VIII	Boiler & Pressure Vessel Code
IS 8451	Indian Standard for Gas Cylinder Testing
GOI Cylinder Rules	Government of India Gas Cylinder Testing Rules
CGD Compliance	City Gas Distribution requirements for CNG & industrial gases

Configurations

Available to match your test bay.

The AVET is available in multiple configurations to cater to varying industrial testing needs.

Config · 01

Customizable Pressure Ranges

Supports low, medium, and high-pressure cylinders across a wide operating envelope.

Config · 02

Multi-Cylinder Testing

Available with single or multi-cylinder testing chambers for higher throughput.

Config · 03

Advanced Automation & Data Logging

Touchscreen control panel with real-time monitoring and automated test-report generation.

Config · 04

Adjustable Cylinder Holders

Clamps and holders adjust to accommodate different cylinder sizes and diameters.

Downloads

Catalog & GA drawing.

Design / General Arrangement

Download

FAQ

Common questions.

Q01What is the Automatic Volumetric Expansion Test System?

The Automatic Volumetric Expansion Test System (AVET) is a precision hydrostatic testing solution designed and manufactured by Neometrix Engineering Pvt Ltd, India. It fills a gas cylinder with water, pressurizes it to 1.5 times its working pressure, and measures elastic and permanent volumetric expansion to determine whether the cylinder is safe for continued use.

Q02Who manufactures the Automatic Volumetric Expansion Test System?

The AVET is designed and manufactured by Neometrix Engineering Pvt Ltd, a leading test equipment manufacturer based in Noida, India.

Q03What industries use the Automatic Volumetric Expansion Test System?

The AVET is used across gas cylinder testing and certification facilities, industrial gas storage and distribution, automotive and transportation, petroleum/oil and gas, aerospace and defence, medical and healthcare, and firefighting and safety equipment sectors.

Q04Is the Automatic Volumetric Expansion Test System customizable?

Yes, Neometrix offers customized versions of the AVET tailored to specific pressure ranges, cylinder types, single or multi-cylinder testing chambers, and customer-specified requirements.

Q05Does the Automatic Volumetric Expansion Test System comply with relevant standards?

Yes, the AVET is designed to comply with ISO 6406, EN 1968, DOT CFR-49, ASME Boiler & Pressure Vessel Code Section VIII, IS 8451, and Government of India (GOI) gas cylinder testing rules, along with customer-specified requirements.

Q06What are the key features of the Automatic Volumetric Expansion Test System?

Key features include automated data acquisition, a self-lubricating pump system, infinitely variable cycling speed, a robust stainless steel frame, and a fully enclosed operator-safe housing that generates no heat, flame, or sparks.

Q07Which cylinder types can the Automatic Volumetric Expansion Test System test?

The AVET tests CNG, Oxygen, Hydrogen, Nitrogen, CO2, Argon, and SCBA (Self-Contained Breathing Apparatus) cylinders, in both metal and composite construction types.

Q08What is the pass/fail criteria used by the system?

If the measured permanent expansion is 10% or less, the cylinder is approved for further use. If permanent expansion exceeds 10%, the cylinder fails the test and must be scrapped for safety reasons.

Q09What after-sales support does Neometrix provide?

Neometrix provides comprehensive after-sales support including installation, commissioning, operator training, preventive maintenance, and on-site service for the Automatic Volumetric Expansion Test System.

Q10How can I get a quotation for the Automatic Volumetric Expansion Test System?

You can request a quotation by contacting Neometrix Engineering Pvt Ltd through the website at https://neometrixgroup.com/products/automatic-volumetric-expansion-test-system or by calling +91-7777-876-876.

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