Pressure packings and oil wipers

CNGS Piston rod packing

STASSKOL manufactures piston rod packings for a wide variety of applications. For CNG (LPG) filling station compressors, a new gas-tight piston rod packing “Compressed Natural Gas Solution” has been developed, which has significantly lower leakages than the standard piston rod packing.

The BOSS oil wiper packing has also been included in the piston rod packing, but the high gas-tightness is due to the new design principle. Instead of the standard gapped sealing ring pairs, highly elastic sealing lips are used. The sealing lips consist of the special PTFE compound SK301, which was developed and manufactured at the in-house Material Center. The SK301 combines excellent tribological properties and high elasticity. In order to work against wear, the sealing lips were developed constructively resistant to deformation. With the CNGS, STASSKOL has placed an exceptional gastight packing on the market, which effects highly efficient compression because of minimum leakages, i.e. more standard cubic meters’ methane yield per kW of gas fed. Super gastight – super savings – super compact!

AIRS Piston rod packing

STASSKOL manufactures piston rod packings for a wide variety of applications. A special packing was developed for air applications, the AIRS – Air Solution, which differs optically clearly from the standard.

The individual packing cups are assembled in a packing casing, which also includes the gas-tight cooling circuit. To keep the installation space of the entire unit as small as possible, the sealing cartridge is installed directly in the cylinder head without a separate packing flange. Three of the patented STASSKOL single sealing rings are combined with a pressure breaker ring. Complemented by the PTFE material specially developed for air operation, this design guarantees an outstanding service life.

LESS Static pack

A compressor relieves pressure via the piston rod packing after shutdown. The installation of a static pack LESS (Low Emision Sealing Solution) prevents the escape of process gas into the atmosphere during machine downtime, therefore avoiding any leakages, and resulting in a zero emission system.

After compressor shutdown, the static pack is activated via a controlled supply of process gas; therefore, an additional gas source is not needed.

Intermediate packing

In reciprocating compressors the compression chamber is sealed against the distance piece by means of a piston rod packing. 100% sealing efficiency is technical not possible even in case of piston rod packings with a buffer gas system there is a possibility that process gas is able to enter the first distance piece.

Therefore, when compressing flammable, explosive or toxic gases the compressor layout usually includes a double distance piece and the two distance pieces are separated by so-called intermediate packing. This avoids the formation of a dangerous gas mixtures. Intermediate packings can be classified into purge, non-purged and buffered versions.

SOSS – Standard Oil Sealing Solution

The SOSS – Standard Oil Sealing Solution – can be used in compressors of a horizontal, vertical or angled design. The packing are exclusively applied in crosshead machines.

Oil wiper rings are made of white bronze, gray cast iron, bronze, white metal or PTFE.

The figure shows the SOSS in combination with a buffer gas unit.

BOSS – Balanced Oil Sealing Solution

The BOSS – Balanced Oil Sealing Solution – is an innovative scraper design. These oil wiper packing is characterized by a high scraping efficiency and tightness that avoids direct oil passage and overflowing process gas from the intermediate distance piece.

The non-metallic oil wiper packing combines two 3-piece main scrapers, a tension ring and a pre-scraper. The scrapers are made of PTFE an PEEK materials produced in-house. Due to the materials the piston rod is preserved.

The BOSS was already registered for a patent.