Page 20 - Steam Turbines Design, Applications, and Rerating

Chapter
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Introduction

1.1 Why Mechanical Drive Steam Turbines
Are Applied
Dependability and versatility of equipment are vital to today’s process
plants, to pharmaceutical producers, mining interests, and a host
of other users including, of course, petroleum, petrochemical, and
chemical-process industries. Operating pressures and temperatures
are constantly rising; single-train capacities grow by leaps and bounds;
continuity of service becomes the vital force; and economics demands
longer and longer periods between overhauls.
Steam turbines are faithful partners to the process industries. They
have proved their basic reliability and today are showing a new versa-
tility by keeping pace with every demand for higher capacity, speed,
and reliability.
Wherever you look in the process industries, there are more mechan-
ical drive turbines; wherever you look, both horsepower and speed go
up, year after year. And wherever you look, technology advances are
being incorporated into modern steam turbines. Many manufacturers
deserve to be recognized for their ability to solve the tougher steam
turbine application problems. Through advanced planning, imagina-
tive research, persistent development, and painstaking evaluation,
engineers have in the last quarter of this century created a whole new
turbine generation: machines of sizes and speeds that were only
dreamed of a few decades ago. Multiflow exhausts, solid rotors, high-
speed bearings, taller last-stage blades (“buckets”), cam-operated valve
gear and controls, and other highly sophisticated control systems and
computerized designs are a few of the innovations that helped make
this progress.

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