Sealing member for mechanical seals

Patent metadata

Field	Value
Publication number	US-11835137-B2
Application number	US-201816647552-A
Country	US
Kind code	B2
Filing date	Aug 21, 2018
Priority date	Sep 19, 2017
Publication date	Dec 5, 2023
Grant date	Dec 5, 2023

Abstract

A sealing member for mechanical seals, which is a peroxide vulcanized molded article of a hydrogenated nitrile rubber having a bound acrylonitrile content of less than 20% and an iodine number of 20 mg/100 g or less. The sealing member for mechanical seals is obtained as a peroxide vulcanized molded article of a hydrogenated nitrile rubber composition comprising 0 to 5 parts by weight of carbon black, 20 to 100 parts by weight of silica, and 0.5 to 3 parts by weight of silane coupling agent, based on 100 parts by weight of hydrogenated nitrile rubber, and preferably further compounding 50 parts by weight or less of titanium oxide non-reinforcing filler. The obtained vulcanized molded article is to provide a sealing member for mechanical seals that can achieve desired LLC resistance, and that has excellent compression set characteristics, cold resistance, processability, hardness, etc.

First claim

The invention claimed is:

1. A static sealing member, which is a peroxide vulcanized molded article of a hydrogenated nitrile rubber composition comprising 20 to 100 parts by weight of silica and 0.5 to 3 parts by weight of silane coupling agent, based on 100 parts by weight of hydrogenated nitrile rubber having a bound acrylonitrile content of less than 20% and an iodine number of 20 mg/100 g or less,
wherein the static sealing member is
a cup gasket or
a bellows of a mechanical seal of a water pump.

2. The static sealing member for mechanical seals according to claim 1 , wherein the hydrogenated nitrile rubber composition, in which 5 parts by weight or less of carbon black is further compounded, is used.

3. The sealing member for mechanical seals according to claim 2 , which has a volume change rate of 4% or less after dipping in a 30 volume % LLC aqueous solution at 150° C. for 300 hours.

4. The static sealing member for mechanical seals according to claim 1 , wherein the hydrogenated nitrile rubber composition, in which 50 parts by weight or less of titanium oxide non-reinforcing filler is further compounded, is used.

5. The sealing member for mechanical seals according to claim 4 , which has a volume change rate of 4% or less after dipping in a 30 volume % LLC aqueous solution at 150° C. for 300 hours.

6. The sealing member for mechanical seals according to claim 1 , which has a volume change rate of 4% or less after dipping in a 30 volume % LLC aqueous solution at 150° C. for 300 hours.

Assignees

• Nok Corp

Inventors

• Abe Shunsuke
• Murakami Hideyuki

Classifications

• F16J15/3284 Primary

  characterised by their structure; Selection of materials · CPC title

• C08K3/04

  Carbon · CPC title

• C08K3/22

  of metals · CPC title

• C08K5/14

  Peroxides · CPC title

• C08L15/005

  Hydrogenated nitrile rubber · CPC title