Installing Mechanical Seals

INSTALLING MECHANICAL SEALS.

By Er. Laxman Singh Sankhla B.E.Mech., Chartered Engineer Jdh!"r, India Mail I#$ laxman%%%&''()yah.c.in INSTALLING MECHANICAL SEALS.

Prior to the installation installation of a Mechanical Seal Cartridge Cartridge it is important important to check  the following: •

The Stuffing Box is clean and free from dirt, sand and burrs etc.

•

The Pump Shaft and Stuffing Box Bore are concentric.

•

The land !ace is s"uare to the Pump Shaft.

The The proc proced edur uree for for chec checki king ng the the s"ua s"uare rene ness ss and and Shaf Shaftt to Stuf Stufffing ing Box Box eccentricit# is accomplished b# the use of $ial Test Test indicators. This is illustrated  below:

DIAL TEST INDICATORS CONNECTED TO THE PUMP SHAFT

%n# eccentricit# between the Pump Shaft and the Stuffing Box will result in runout of the Seal !ace and Seat during operation. &xcessi'e runout (more than ).))* inches or + microns- will result in premature Seal failure. %n# significant outofs"uareness ().))* inches or + microns- between the Pump Shaft and land !ace will cause an une'en axial loading of the Seal Seat and !ace. This will result in premature Seal failure. The $ial Test /ndicators ($T/0s- are mounted on the Pump Shaft. /n the abo'e diagram the Plunger T#pe $T/ is placed against the land !ace. The 1e'er  T#pe $T/ is placed within the Stuffing Box Bore. %s the Pump Shaft is rotated an# eccentricit# or outofs"uareness is recorded. %n# excessi'e eccentricit# or outofs"uareness must be eliminated before the Mechanical Seal can be installed. This is usuall# achie'ed b# unbolting the Pump Bearing 2ousings and re dowelling the housings in the correct location.