GNR Shanghai Oil-free SF6 gas compressors

Oil-free SF6 gas compressors built for critical service

Weiyang is a manufacturer of SF6 gas maintenance equipment. GNR oil-less compressors are developed for the exacting requirements of safe, reliable industrial gas compression service: SF6 gas, helium, hydrogen and noble gases, with no oil contamination and no cooling water.

Oil-free by design

Up to four oil-free single acting cylinders on an S type crosshead crankcase, with a gas-tight design and special sealing.

Air-cooled throughout

Heat exchanger, compression cylinders and crankcase are all air cooled, so no cooling water circuit is needed on site.

Who buys them

Switchgear makers, utilities, EPC contractors and OEMs, including CEPRI, ABB (Beijing), Mitsubishi Group and ALSTOM (Suzhou).

Configurable pressures

Standard configurations when they fit, tailored compressor and control design when they do not.

Product Range

Three machines, one oil-free platform.

The Numbers Behind the Factory

4Standard compressor models
6–80Nm³/h covered by the standard range
2.2–22kW motor range
0Drops of oil in the gas path

Industries We Supply

Where these compressors are used, and what each sector actually needs from them.

Knowledge Centre

Reference material for engineers specifying gas handling equipment.

How an Order Runs

  1. Send the duty point

    The gas, the flow required, and the suction and discharge pressures.

  2. Standard model or tailored design

    We say which of the four standard machines fits, or design the compressor and controls to the duty if none does.

  3. Build and test

    Oil-free cylinders on an S type crosshead crankcase, gas-tight and air cooled throughout, tested before despatch.

  4. Field support

    Machines are built to be serviceable in the field rather than returned to a workshop.

Frequently Asked Questions

Why does an SF6 compressor have to be oil-free?

Because oil carried into the gas contaminates it, and SF6 is expensive and tightly regulated. Once oil is in the gas the recovered charge is no longer usable as it stands, which defeats the purpose of recovering it.

Do these compressors need cooling water?

No. Heat exchanger, compression cylinders and crankcase are all air cooled, so there is no water circuit to install, freeze-protect or maintain at the site.

What if my duty point is outside the standard chart?

Then the compressor and control design are tailored to it. Rounding up to the next catalogue machine wastes power and makes recovery at low suction pressure harder, so it is not the right answer.

Can the same machine handle helium or hydrogen?

The platform covers SF6, helium, hydrogen and noble gases, but the sealing and materials are specified for the gas you name. Tell us which gas at the enquiry stage rather than after the machine is built.

Send us your duty point

Tell us the gas, the flow you need and the suction and discharge pressures. If a standard model fits we will say so; if it does not, the compressor and control design are tailored to the duty.