Representative Sampling—Engineered by Welker

From refined products to natural gas and crude oil, Welker designs and manufactures standards-compliant sampling systems—automatic sample pumps, probes, constant pressure cylinders, and containers—so your analysis reflects the true composition of your product.

Why Representative Sampling Matters

Accurate measurement depends on a representative sample. Welker systems help reduce bias, protect light ends, and prevent phase changes so your quality control, custody transfer, and regulatory reporting are backed by defensible data.

Built to Standards & Best Practice

• ASTM D4177 – Automatic sampling of petroleum & petroleum products.
• ISO 3171 – Automatic pipeline sampling of petroleum liquids.
• ASTM D4057 – Manual sampling of petroleum & petroleum products.

Sampling Solutions by Process Fluid

Welker offers end-to-end sampling—from extraction to containment—tailored to your product, pressure class, and operating environment.

Natural Gas

Sampler, probes, and sample conditioning for analysis and measurement quality.

Crude Oil

Automatic pipeline sampling and constainers for BS&W, density, and composition checks.

Light Liquid

Represetnative samples from variable streams with appropriate extraction and control.

Refined Products

Gasoline, diesel, jet fuel. Proportional batch sampling and composite collection for custody transfer.

LNG

Capture representative samples from cryogenic streams designed to maintain phase stability, minimize boil-off, and deliver accurate analysis for liquefied natural gas.

Featured Sampling Products

Engineered components that form the backbone of reliable, representative sampling programs.

Samplers

Any probe, any process. Fixed or retractable designs for gas and liquid applications.

Constant Pressure Cylinders

Precision-honed bores for sample integrity; select models DOT-rated for compliant transport.

Containers

Engineered to meet industry standards, Welker containers ensure representative samples remain stable and uncompromised during handling and transport.

Industires & Use Cases

Engineered components that form the backbone of reliable, representative sampling programs.

Refineries & Terminals

Batch and custody transfer sampling for finished fuels, blends, and additives.

Midstream & Pipelines

Automatic sampling and conditioning for metering, compliance, and audits.

Utilities & Power

Natural gas sampling for analysis, odorization, and measurement assurance.

Labs & Inspection

Containers and cylinders designed for integrity through transport and testing.

Quality in Every Detail

Welker's sampling expertise, in-house engineering, and meticulous manufacturing to every system . From precision-honed cylinders to reliable sample pumps and probes, we build equipment that stands up to the field—and stands behind your measurements.

• Application-specific materials and finishes
• Traceable documentation & serial identification
• Factory testing and inspection

Support & Services

Let's Build a Turnkey Sampling Solution

Share your process fluid, flow/pressure, and compliance needs—Welker will provide you a turnkey solution built specifically for your application.