Gaskets and Seals for Pulp and Paper Applications

From a fluid sealing perspective, pulp and paper manufacturing can be characterized as severe service, involving the use of aggressive chemicals, caustic fluids and high temperatures and pressures. Gaskets and seals for pulp and paper applications must be capable of servicing these demanding conditions. This blog describes how CRG can assist pulp and paper manufacturers to successfully address their fluid sealing needs and challenges.

Pulp and paper mills, depending upon their end product and manufacturing process, can have unique needs. Some mills produce a variety of end products and work in batch mode. Others produce a more limited product mix and use continuous digesting and processing to produce their products. The fluid sealing needs of each type of mill can therefore be quite different.

Given this fact, CRG can work with individual mills to optimize the supply of fluid sealing products. We can work with mill purchasing and stores to ensure that the supply of product is both economical and reliable and, at the same time, assist plant engineering and maintenance with material and gasket selection and installation guidance and training. Our objective in all cases is to reduce the incidence of gasket failures and problems, streamline the supply process, and enhance process performance and safety.

Some examples of fluid sealing products that CRG can supply to pulp and paper mills include the following:

Gaskets and seals from Tealon**®** sheet. Tealon® sheet from Teadit is an excellent material choice for applications involving strong caustic fluids and aggressive chemicals. In hot compression tests, gaskets produced from Tealon® sheet outperformed those made from skived PTFE. In these tests, the skived PTFE gasket showed a very high leak rate, losing 60% of its initial pressure by the end of the test. In comparison, the Tealon® gasket lost only 6% of its initial pressure by the end of the test and showed a leak 10 times less than that of the skived PTFE gasket. This superior performance can translate into reduced costs and improved equipment uptime and availability. Tealon® sheet is available in a range of styles from which CRG can fashion gaskets and seals to suit specific applications and equipment.

Gaskets and seals from GR1700 sheet. Teadit GR1700 – SIGRAFLEX APX2 Hochdruck is a multilayer, high-strength gasket sealing sheet designed for high-temperature applications. Gaskets made from GR1700 sheet perform particularly well in critical applications due to their high mechanical strength and the blow-out resistance, working pressure resistance up to 3600 psi (250 bar), excellent chemical resistance, very low cold or hot relaxation, and the maximum permissible gasket stress.

Compression packing. CRG supplies Teadit compression packing to service pulp and paper applications. Styles that we often supply for pulp and paper applications include the following:

  • Style 2002 packing is manufactured from pure carbon yarn, which is interlock braided and impregnated with proprietary lubricants and graphite particles which fill voids, block leakage, and act as a break-in lubricant. The end product has a low coefficient of friction and tends to wear more evenly than most braided packings.

  • Style 2007 packing is an interlock braid, utilizing TEADIT’s EG8G-S PTFE/graphite yarn and a high temperature break-in lubricant. EG8G-S yarn is formed from expanded PTFE in which fine particles of pure graphite have been encapsulated. The resulting packing combines the chemical resistance of PTFE with the heat dissipation characteristics of graphite, thus allowing much higher shaft speeds than conventional PTFE packings.

  • Manufactured by an advanced method of braiding and construction, packing Style 2020 offers excellent performance in pulp and paper applications. Due to the technological edge of its filament, that contains a special additive encapsulated by pure PTFE, and this constructive feature offers excellent heat dissipation, which is usually generated by the sealing system. The result is excellent sealability, particularly when compared with other PTFE packings.

  • Style 2777 packing is a high-performance packing that is well suited to applications where graphite impregnation may not be acceptable. It can handle steam, water, acids and other chemical and solvent applications. This style has multiple uses in chemical plants and pulp and paper mills, and is regularly used in rotating and reciprocating pumps, washer journals, liquor pumps, refiners and digesters.

  • Style 2030 is braided from meta-aramid yarn, each strand impregnated with PTFE-dispersion during the braiding process, and lubricated with an inert mineral oil. The high mechanical strength of the meta-aramid fiber, combined with the elaborate braiding process, results in a soft and pliable packing with excellent mechanical and chemical resistance. Because of the low coefficient of friction, shaft wear is largely avoided, even at high shaft speeds. No excessive heat build-up between the packing rings and the turning shaft; the packing runs cool, remains soft and flexible, resulting in longer service life. Style 2030 is recommended for all kinds of pumps, mixers, agitators, reactors, etc. for the chemical industry, pulp and paper, sewage plants, and many more. It is suitable for use with a wide variety of media in many different processes, including water, sewage, steam, solvents, chemicals, acids and caustics, as well as general service applications where a mechanically strong packing is required.

If you are seeking gaskets and seals for pulp and paper applications, or are interested in finding out how CRG can address your fluid sealing needs, our sales teams will be delighted to speak with you.

To find out more, please contact our sales department directly at