Custom Seal Installation

MD&A Parts Division has been providing high-quality turbine-generator components to the power generation industry for more than two decades.  Our patented Guardian® packing rings and Vortex Shedder® spills, as well as our conventional steam turbine packing, are custom installed by trained MD&A Parts Division staff.  We provide all the necessary machine tooling and technical experience necessary to ensure a trouble-free installation.

Why Packing & Seal Installation is So Critical
Turbine seals prevent steam from leaking between the rotating and stationary components. Having excessive clearance due to either component distortion or through seal wear reduces turbine efficiency. Having clearances that are too tight, will result in turbine rubs and operational problems.

Installation of packing rings and seals by experienced turbine technicians is a key part of your outage. Skilled technicians can custom machine your replacement seals to best fit distorted components, and establish proper seal clearances. Having the proper tooling and skills enables MD&A to perform this work efficiently and with great precision.

The most common distortions are:

• Elliptical Bore Distortion- Turbine Diaphragms, Blade Rings, and glands cases frequently become elliptical from years of service. This changes the seal radial clearances, resulting in seal rubs and subsequent wear and increased seal clearances. Decreased sealing efficiency, decreases turbine efficiency and output. Using the distorted component dimensions, our technicians and Engineers design and manufacture the replacement seals to better accommodate the distortion. Our Seal technicians provide the final adjustment to accommodate the uneven distortion within the component and frequently make radial adjustments to offset minor component misalignment.
• Dishing Distortion of the Diaphragm- The axial relationship between seal teeth and the turbine rotor is critical to a smooth-running and properly sealed turbine. As a turbine ages, the interstage diaphragms/nozzles may creep axially due to differential steam pressures. This axial displacement changes the relationship between the stationary seal teeth and the rotor. If the change becomes too great, the rotor will rub the seal teeth, causing vibration and increased seal clearances. With consideration of “As Found” axial clearances, MD&A can custom make and fit packing to restore seal axial clearances.

CNC-Equipped Containerized Unit
MD&A not only provides precision design engineering of manufactured rings and seals but sends expert technicians with 20 to 30 years of experience in the field for installations and repairs.

Our crews arrive with a fully-equipped mobile containerized machine shop, complete with advanced CNC equipment, printer, computer, high-speed wireless access, and all necessary tools.

See our Onsite Seal Services Video here

Learn more about the other Steam Turbine Parts that MD&A offers.