How Closed Loop Sampling Systems Work

A closed loop sampling system creates a sealed circuit between your process line and the sample container, ensuring that the process fluid never contacts ambient air during extraction. The system typically consists of a sampling panel with isolation valves, a purge/vent circuit, and a sample cylinder connection point.

The operational sequence follows four steps: (1) Connection — the sampling assembly connects to a process tap via flange or threaded fitting; (2) Purging — process fluid flushes through the entire circuit to displace residual material; (3) Filling — the sample flows into the cylinder under controlled pressure; (4) Isolation — all valves close and the sealed cylinder is disconnected for lab analysis. The entire cycle takes 3-8 minutes depending on fluid properties and purge volume requirements.

For volatile streams (LPG, naphtha, gasoline), constant-pressure piston cylinders maintain the sample at process pressure, preventing light-end flash vaporization that would corrupt RVP and distillation analysis. For stable liquids (diesel, lubricants), standard stainless steel cylinders provide reliable service at lower cost.

Key Technical Specifications

ParameterTypical Range
Design Pressure2.0 - 6.4 MPa (Class 150 - 400)
Design Temperature-40 to +350 C
Wetted Material316L Stainless Steel (standard); Hastelloy C-276 (corrosive service)
Cylinder Volume150 mL - 4 L (standard: 500 mL, 1 L)
Connection StandardANSI B16.5 flange / NPT threaded / DIN
CertificationASME U-Stamp, PED 2014/68/EU, ATEX, GB/T 150

Common Applications

  • Oil Refineries: Crude feed sampling, gasoline blend stock, diesel, jet fuel, LPG, naphtha
  • Petrochemical Plants: Ethylene/propylene feedstocks, aromatics (BTX), polymer intermediates
  • Natural Gas Processing: NGL, condensate, rich/lean glycol, amine solutions
  • Pharmaceutical: Solvents, reaction intermediates, API precursors (GMP compliant)

Certifications & Standards Compliance

All Wanan sampling systems are manufactured under ASME U-Stamp certification at our Honghu, Hubei facility. Material traceability per EN 10204 3.1 is maintained throughout. For European installations, PED 2014/68/EU compliance is available. For explosive atmosphere installations, ATEX/IECEx certification is provided. Sour service (H2S) applications use NACE MR0175/ISO 15156 compliant materials.

Storage Tank Sampler

Storage Tank Sampler

Add to quote

Storage Tank Sampler - Sampling System | Wanan Technology
Storage Tank Sampler - Product Photo (Sampling System) | Wanan Technology
Storage Tank Sampler - Product Photo (Sampling System) | Wanan Technology

Related Products

Related products

FAQ

A closed loop sampler is a safety device used to collect liquid samples from pipelines or storage tanks without exposing operators to hazardous chemicals. Wanan closed loop samplers comply with API MPMS 8.2 standard and feature a sealed design that returns purge fluid back to the process, eliminating VOC emissions.

Wanan flame arrestors are certified to ISO 16852, ATEX (European Explosive Atmospheres Directive), and EN 12874 standards. We provide type test reports for IIA, IIB, and IIC gas groups. All products are manufactured in our ISO 9001:2015 certified facilities.

Yes. Wanan Technology is a registered qualified supplier for Sinopec, PetroChina, CNOOC (China), ExxonMobil, LukOil (Russia), ENI (Italy), KazMunayGas (Kazakhstan), and PDVSA (Venezuela), among others.

Wanan Technology has manufacturing facilities in Germany, USA, and China. We also have inventory and sales service centers in UAE to serve Middle East and global customers with fast delivery.

Wan’an Technology’s closed sampler is suitable for liquid sampling scenarios involving toxic and hazardous media in petrochemical, natural gas, oil refinery, and tank farm industries. It complies with API MPMS 8.2 standards, prevents operators from coming into contact with hazardous substances, and meets HSE environmental emission requirements.

A: Standard products ship within 2-4 weeks from order confirmation. Custom-engineered solutions typically require 6-8 weeks depending on specification complexity. For urgent projects, we offer expedited production upon request — contact our sales team with your timeline and we will work out a schedule.

A: Our products comply with major international standards including ISO 3170 (petroleum sampling), API MPMS 8.1/8.2, ATEX for explosive atmospheres, ASME, and EAC. DOT and TPED certifications are available for sample cylinders. We provide full certification documentation and material test certificates with every order.

A: Yes. We offer sample units for evaluation purposes. Upon approval, we ship one or two units so you can verify compatibility with your application, materials, and site conditions before committing to a volume order. Shipping costs may apply depending on destination.