Hydrostatic Expansion & Porous Mass Audit Rigor
Every production batch undergoes 100% water-jacket volumetric expansion testing and destructive porous mass porosity verification under direct PESO inspection supervision.
100% Water-Jacket Hydrostatic Expansion Testing
Cylinders are pressurized in sealed water jackets to 250 kgf/cm² (for IS 7312 DA) or 70 kgf/cm² (for IS 3196 Part 2 High Test RG) to measure total and permanent volumetric expansion, enforcing a strict ≤10% permanent expansion limit.
Calcium Silicate Porous Mass Density & Crushing Audit
Destructive core sampling verifies that the monolithic calcium silicate mass achieves exact 90%–92% porosity and a minimum compressive crushing strength of ≥22 kgf/cm² for stable Acetone absorption.
100% Pneumatic Leakage Verification at Working Pressure
Fully assembled cylinders fitted with IS 3224 brass valves are submerged under water and pressurized with dry air/nitrogen at 12–40 kgf/cm² to ensure zero seam or valve thread bubble leakage.
Third-Party Validation & Heat Traceability
BTPS provides complete batch test certificates backed by TÜV SÜD ISO 9001:2015 audit trails and official PESO inspection logs.
JSW Steel Heat-Number & Ultrasonic Flaw Traceability
Every batch is cross-referenced with primary JSW Steel mill certificates (IS 6240 / IS 15914) and subjected to ultrasonic wall thickness and flaw detection before drawing.
TÜV SÜD ISO 9001:2015 & PESO Dispatch Authorization
Batch test logs are validated under TÜV SÜD ISO 9001:2015 quality standards (Cert Registration #99 100 23469) and approved by PESO officers for zero-failure field deployment.
Hydrostatic Test Pressures & Volumetric Expansion Limits
Detailed hydrostatic test parameters across BTPS industrial gas cylinder categories certified under BIS and PESO standards.
| Cylinder Category & Standard | Hydrostatic Test Pressure | Pneumatic Leak Test Pressure | Max Working Pressure | Max Permanent Expansion |
|---|---|---|---|---|
| DA Cylinders — Welded (IS 7312) | 53 kgf/cm² | 40 kgf/cm² | 16 kgf/cm² | ≤ 10% of Total Expansion |
| DA Cylinders — Seamless (IS 7312) | 250 kgf/cm² | 150 kgf/cm² | 16 kgf/cm² | ≤ 10% of Total Expansion |
| Standard RG Cylinders (IS 3196 Part 2) | 45 – 50 kgf/cm² | 12 kgf/cm² | 27.88 – 33.33 kgf/cm² | ≤ 10% of Total Expansion |
| High Test HT RG Cylinders (IS 15914 Steel) | 70 kgf/cm² | 12 kgf/cm² | 46.67 kgf/cm² | ≤ 10% of Total Expansion |
Monolithic Mass Core Sampling & Compressive Audits
To prevent hazardous acetylene gas decomposition, the porous mass filling inside DA cylinders must remain completely monolithic, void-free, and rigidly bonded to shell walls.
Our Belagavi quality control laboratory cuts open statistical sample cylinders from each autoclaving batch, extracting core samples to measure porosity, bulk density, crushing strength, and thermal safety space.
Porous Mass Audit Metrics
- Porosity Verification: Water displacement testing confirms exact 90%–92% capillary pore volume.
- Compressive Crushing Test: Hydraulic press core testing confirms ≥22 kgf/cm² crushing resistance.
- Top & Bottom Clearance Audit: Physical inspection confirms zero top/bottom mass settlement voids.
- Acetone Solvent Absorption: Tare weight checks verify correct solvent saturation volume.
X-Ray Radiography & Mechanical Weld Testing
Submerged Arc Welded (SAW) circumferential and longitudinal seams are subjected to rigorous non-destructive and destructive evaluation.
100% X-Ray Radiography
Radiographic inspection of welded seams detects internal micro-porosity, lack of penetration, or slag inclusions before stress relieving.
Thermal Stress Relieving
Welded shells pass through computerized normalizing furnaces to relieve residual drawing and welding stresses prior to hydro testing.
Tensile & Root/Face Bend Tests
Destructive coupon testing on Universal Testing Machines (UTM) confirms weld joint tensile strength equals or exceeds parent JSW steel.
Technical FAQ & Specifications
How is volumetric permanent expansion calculated during hydrostatic water-jacket testing?
How is volumetric permanent expansion calculated during hydrostatic water-jacket testing?
During hydrostatic testing, the cylinder is pressurized inside a water jacket, displacing water into a burette to measure total expansion. Upon pressure release, permanent volumetric expansion is calculated as a percentage of total expansion, which must not exceed 10% under IS 3196 and IS 7312 standards.
What specific destructive tests are conducted on the porous mass of Dissolved Acetylene cylinders?
What specific destructive tests are conducted on the porous mass of Dissolved Acetylene cylinders?
Sample cylinders from each batch are cut open to perform core extraction tests verifying 90%–92% porosity, bulk density, crushing strength (minimum 22 kgf/cm²), and complete absence of internal clearance or settlement voids per IS 7312.
Are individual cylinder hydrostatic test certificates provided with commercial batch shipments?
Are individual cylinder hydrostatic test certificates provided with commercial batch shipments?
Yes, every batch dispatched from our Belagavi plant is accompanied by an official Manufacturer’s Batch Test Certificate detailing individual cylinder serial numbers, tare weights, hydrostatic test pressures, permanent expansion values, and PESO inspection sign-offs.