The Vertical Transportation Handbook E-Book

• Herausgeber: John Wiley & Sons
• Kategorie: Wissenschaft und neue Technologien
• Sprache: Englisch

Seitenzahl: 1007

Veröffentlichungsjahr: 2010

Beschreibung

This new edition of a one-of-a-kind handbook provides an essential updating to keep the book current with technology and practice. New coverage of topics such as machine-room-less systems and current operation and control procedures, ensures that this revision maintains its standing as the premier general reference on vertical transportation. A team of new contributors has been assembled to shepherd the book into this new edition and provide the expertise to keep it up to date in future editions. A new copublishing partnership with Elevator World Magazine ensures that the quality of the revision is kept at the highest level, enabled by Elevator World's Editor, Bob Caporale, joining George Strakosch as co-editor.

Leseprobe

Table of Contents

Title Page

Copyright

Preface

Acknowledgments

Contributors

1 The Essentials of Elevatoring

Early Beginnings

Elevator Safety Devices

Hydraulic Elevators

Elevatoring

Traction Elevators

Gearless Traction Elevators

Geared Traction Machines

Hydraulic Elevators

Escalators and Moving Walks

Dumbwaiters and Materials-Handling Systems

Handicapped Lifts

Study of Elevatoring

Modernization

2 The Basis of Elevatoring a Building

Early Population

Elevator Traffic

Pedestrian Planning Considerations in Elevatoring

Positioning of a Building's Vertical Transportation System

Modernization

3 Passenger Traffic Requirements

The Elevator Trip

Requirements Of Good Elevator Service

Calculating The Time Factors

4 Incoming Traffic

Introduction

Incoming Traffic Period Interval

Incoming Traffic Operation of Elevators

Down Traffic During Up-Peak

General Conclusions

5 Two-Way Traffic

Importance Of Two-Way Traffic Considerations

Two-Way And Interfloor Traffic Requirements

Sample Calculations

Elevator Operation During Two-Way And Interfloor Traffic

General Conclusions

6 Outgoing Traffic

Importance Of Outgoing Traffic

Outgoing Traffic Requirements

Calculations For Outgoing Traffic

Sample Calculations

Special Operations

General Conclusions

7 Elevator Operation and Control

Part I: General Overview of Computer Technology as Related to Elevator Operation

Part II: Operation and Control Systems

Operation Systems

Traffic Definitions and Operations

Special Operating Features

Adjusting Operation to Traffic

Advances in Operational Strategy—Artificial Intelligence

Needs for Future Development

About the Author

8 Space and Physical Requirements

Space for Elevators

Required Space

Overhead and Pit Requirements

Elevator Reactions

Additional Machine Room Considerations

Elevator Layouts

Special Layout Requirements

About the Author

9 Escalators and Moving Walks

Escalators Versus Moving Walks

Effective Application

Traffic-Handling Ability

Arrangement and Location

Space Requirements

Features Of Escalators And Moving Walks

Escalators Versus Elevators

Calculating Escalator Or Moving Walk Requirements

Application Of Escalators And Moving Walks

About The Author

10 Elevatoring Commercial Buildings

Definition

Population

Elevator Traffic in Commercial Buildings

Layout and Grouping of Elevators

Transfer Floors

Elevator Operation in Commercial Buildings

Typical Office Building Elevatoring

Rules of Thumb

Maximum Elevator Size in Office Buildings

Elevatoring Stores

Passenger Elevators in Garages

Professional Buildings

Merchandise Marts

Industrial Buildings

Summary

11 Elevatoring Residential Buildings

Population

Characteristic Traffic and Intensity

Calculating Elevator Requirements

Elevator Equipment and Layout

Hotels and Motels

Service Elevators

Sample Hotel Elevatoring

Apartments

Sample Calculations

Dormitories and Residence Halls

Senior Citizen Housing

Elevators in Residential Buildings

Elevators in Private Residences

Summary

12 Elevatoring Institutional Buildings

Definition

Population

Elevator Traffic in Institutional Buildings

Hospitals

Institutions For Long-Term Care

Secondary Schools, Universities, and Colleges

Courthouses

Jails

Museums, Exhibits, Sports Arenas, and Observation Towers

General

Operation

13 Service and Freight Elevators

Service and Freight Elevators

Freight Elevators

Elevator Design

Service Elevators

Operation of Service and Freight Elevators

Elevators in Industrial Plants

Elevators in Warehouses

Elevators in Garages and For Off-Street Loading

Other Freight and Service Elevator Considerations

Unusual Installations

About The Authors

14 Nonconventional Elevators, Special Applications, and Environmental Considerations

Nonconventional Elevator Applications

Multipurpose Buildings

SKY Lobby Elevatoring

Double-Deck Elevators

Observation and Outside Elevators

Inclined Elevators

Shipboard Elevators

Elevators in Mines

Industrial-Type Elevators

Rack and Pinion Elevators

Building Compression

Car Ride

Wind Effects and Building Sway

Stack Effect

Earthquake Design

Noise

Elevators in Problem Locations

Flooding

Trailer Truck Elevator

Parking Garage Elevator With Horizontal Carriage

Nonelevator Vertical Transportation

Summary

About The Author

15 Automated Materials-Handling Systems

Developing Technology

Automated Materials Handling in Public Buildings

Pneumatic Tube Systems

Selective Vertical Conveyor (SVC)

Electric “CAR on Track” Conveyor Systems

Tote Box Lifts

Automated Cart Lifts

Track Systems—Overhead

Track Systems—in-Floor

Automated Guided Vehicle (AGV) Systems

Pallet Lifts

Economics

Summary

About the Author

16 Codes and Standards

Introduction

History

Overview of Applicable Codes and Standards

Code Adoption

Enforcement Conflicts

Conflict Resolution

Code Coordination

Future Trends

Locating Codes and Standards

Conclusion

About the Author

17 Elevator Specifying and Contracting

Preparing to Bid

Specifications

Construction Specification Institute

Codes and Standards

Performance Criteria

Proposal Bidding

Negotiation

Establishing a Contract

Temporary Operation

Acceptance

New Installation Service

Actual Elevator Construction

Approvals

Delivery Scheduling

Relation of Elevator Work to Other Trades

Changes and Alterations

Contract Completion and Acceptance

Elevator Modernization

Summary

About the Author

18 Economics, Maintenance, and Modernization

Cost

Return on Investment

Vertical Transportation Arrangements

Equipment Selection

Elevator Maintenance and Repair

Proposals for Elevator Maintenance

Elevator Modernization

Equipment Survey

Specifications

Safety and Liability

Role of the Consultant

Use of Maintenance Management Software

Summary

Acknowledgments

About the Author

19 Traffic Studies and Performance Evaluation Using Simulation

Introduction

Quantifying Traffic Demand

Traffic Analyzers

Manual Traffic Surveys

Sample Results for Office Buildings

Application of Simulation

Conclusions

Acknowledgments

About The Author

20 The Changing Modes of Horizontal and Vertical Transportation

Introduction

Scissor Jacks

Accelerating Moving Walks

Escalators: Transit Stations

Elevator-Transit Stations

People Movers

Skywalks

Cable-Driven People Movers

Automated People Movers

Water Towers

The Future

About the Authors

Appendix: Literature on Elevators and Escalators

Index of Tables and Charts

Index of Examples

Subject Index

This book is printed on acid-free paper.

Copyright © 2010 by John Wiley & Sons, Inc. All rights reserved

Published by John Wiley & Sons, Inc., Hoboken, New Jersey

Published simultaneously in Canada

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Library of Congress Cataloging-in-Publication Data

The vertical transportation handbook / George R. Strakosch, Robert S. Caporale, editors. – 4th ed.

p. cm.

Includes index.

ISBN 978-0-470-40413-3 (cloth); ISBN 978-0-470-91971-2 (ebk); ISBN 978-0-470-91972-9 (ebk); ISBN 978-0-470-91973-6 (ebk); ISBN 978-0-470-94981-8 (ebk)

1. Elevators. 2. Escalators. I. Strakosch, George R. II. Caporale, Bob.

TJ1370.V476 2010

621.8′77–dc22

2010005154

Preface

It is hard to believe how much the vertical transportation industry has changed since the first edition of Vertical Transportation was published in 1967. Back then the industry was dominated by the major manufacturers and installers, Otis being the most prominent of all. The United States was the major source of equipment, and only Otis was worldwide. I was fortunate to be part of the changes that have taken place. My own career—from Otis to the consulting firm of Jaros, Baum & Bolles, to Elevator World, and, finally, on my own—has been a reflection of some of these changes. In the early years consultants were a minor factor, but that started to change in the 1970s. Competition among manufacturers started to change as companies such as Haughton and Dover gained substantial shares of the market. Otis and Westinghouse dominated the escalator market, but Montgomery and Peelle made inroads. Elevator contractors and suppliers started to take a substantial share of the low-rise and specialized market, and consultants became a factor.

Regarding the latter, I feel I helped the rise of consultants, since they now had a guidebook. The mystery of elevatoring became available knowledge, and the first edition of Vertical Transportation was the source. I was delighted, and somewhat put out, when part of my book was entered as an exhibit in a court case without my being given any credit. I also realized how limited my book was and, in the early 1980s, I decided to update it. Being a consultant myself, I could see where additional knowledge was needed and became cognizant of the changes in the industry that were taking place. I also had the benefit of meeting many of the diverse agencies from both the buyer and seller sides. During my tenure at Jaros, Baum & Bolles, I can safely say that I was involved in many of the major buildings planned or built from 1977 to 1987. It was an exciting time for me, and much of the experience is reflected in the second edition of Vertical Transportation.

Joining Elevator World in 1987 gave me a chance to substantially expand my knowledge of the elevator industry. One of my first chores was to review and classify most of the articles published on various aspects of the industry since Elevator World started publication in 1953. The result was the four-volume “Educational Package” currently available and further expanded. That experience led to the recognition of the need for an expanded educational effort to benefit both the suppliers and buyers of equipment and services. After consultations with Bill Sturgeon, the publisher of Elevator World, and Bob Jacobs, chairman of the board, we decided that seminars were a good way to initiate an educational effort.

Two 8-hour seminars were developed, one for purchasers, specification writers, and users of elevators and escalators and the other for suppliers, installers, and service providers. Written material and slides covering subjects such as equipment choice, application, space requirements, layout development, the various types of operation and control, and forms of service contracts were also prepared. Once we were ready to go, we picked six cities and did a mass mailing both to the Elevator World subscribers and to individuals in various organizations. Our initial seminar was in Boston in March of 1988 and, after expanding our chosen cities to 10, we concluded the series in Los Angeles in December of 1989.

The seminar series gave us a number of collateral results. The need for written educational material expanded, and more literature was required to feed that need. The seminar series was developed into a manual, and other publications, both readily available and newly produced, became popular. We learned that seminars, as such, were too costly and that distance learning was a more effective way to go. A review of the current Elevator World Educational Publications Catalog will attest to the expansion that developed.

I started to receive requests for private consulting and, by mutual agreement, reduced my time with Elevator World. This also gave me the opportunity to consider expanding Vertical Transportation to reflect the current state of the elevator and escalator “art.” (I'm sure anyone totally involved in the field will agree that it is both an art and a science.) I realized that the technicalities of the industry had changed so that specialists needed to be enlisted to cover many aspects. The third edition of Vertical Transportation was a result of the input of these specialists, and I assumed the role of editor. The industry now had a “handbook,” and the effort of the many contributors is greatly appreciated.

The third edition was published in 1998 and became The Vertical Transportation Handbook both to reflect the input of the many experts in the field and to update the status of the industry. The basics remained, with minor updates, and they have withstood the test of time. It continued to show the technology of elevators and people's unchanging reactions to elevators—and they still fret about how long it takes after they push the button before an elevator responds.

For the fourth edition we were fortunate to be able to call upon the same experts, with minor exceptions, to update their contributions. They were also asked to address any changes in their areas that have taken place in the past 10 or more years. Regretfully, one of our contributors, Wayne Gilchrist, has passed away, while some others are joined by younger counterparts and continue to contribute their knowledge to the various chapters. The readers and users of the book will benefit from their input.

Acknowledgments

I am most fortunate to have Bob Caporale as my associate editor for the fourth edition. Bob and I have been friends and associates since I first met him when I joined Jaros, Baum & Bolles in 1977. As editor of Elevator World he brings the most up-to-date view of the elevator industry that anyone can, and his help and efforts are one of the main reasons the fourth edition was possible. I will be eternally grateful.

When I entered the elevator industry as a construction helper in 1946, little did I realize that I would be writing this. It was a job that evolved into a career, and I can honestly say I enjoyed most of the time I have spent in its various aspects. To use a hackneyed saying, I've enjoyed the ups and downs and wouldn't trade one moment of the time.

My appreciation is extended to the many people in the industry who have supported my efforts to record the many aspects of the proper application of elevators and escalators. My special appreciation goes to my wife and family, who have helped me create what I feel is my legacy.

GEORGE R. STRAKOSCH

This fourth edition of The Vertical Transportation Handbook would not have come to fruition were it not for Mouse! Mouse was a big guy who stood 6 feet 4 inches tall, and was one of my best high school buddies, with whom I not only spent much of my teenage years but went on to college with as well. Struggling through the first two years of what in the 1960s was for us young guys a grueling mechanical engineering curriculum, Mouse left school and went to work full time as a draftsman at Jaros, Baum & Bolles (JB&B), an engineering firm in downtown New York City. When I confided in Mouse that my studies were killing me as well, he suggested that I “come on down!” and apply for a job at what we later learned was one of the finest mechanical/electrical engineering companies in the world. After a successful interview with Cal Kort (6 feet 8 inches tall), who not only did the first cut on interviews for the company but also ran the elevator department, I was hired to start work on the world's tallest buildings and largest construction project to date, the twin towers at the World Trade Center. This turned out to be the start of my 45-year career in the elevator industry.

I was blessed to have been pointed in this direction and taken under the wing of Cal Kort and those who succeeded him at JB&B—most of whom, though not nearly as tall as Cal, were truly giants in the elevator industry. Bill Lewis succeeded Cal Kort and brought George Strakosch (6 feet 3 inches) on board, and I literally worked alongside George for 10 years. I had the incredible opportunity to serve my apprenticeship with the previously mentioned leading elevator industry engineers, as well as Chet Chrobot of Otis Elevator Company and Joe Montesano of Westinghouse Elevator Company, who were their companies' sales engineers assigned to work with JB&B and therefore visited us often. It was these folks—in addition to numerous elevator field engineers, mechanics, and adjusters from all of the major elevator companies—that I spent days and in some cases weeks with, on major projects all over the world, and from whom I learned the intricacies of elevator system design, operation and control, testing, and inspection. As a draftsman, project designer, and NAESA-certified Qualified Elevator Inspector (QEI) for JB&B, I absorbed all of the knowledge that I could from those elevator industry people who surrounded me day after day. I am indebted to all of the people I worked for and with, and in particular to George Strakosch, not only for the knowledge that he imparted to me but especially for the bond that he was instrumental in nurturing between Bill Sturgeon and me. Working for and with these giants of the elevator industry has been a blessing for me, and it is because of all these people that I have been able to be a part of the development of this fourth edition of The Vertical Transportation Handbook.

In 1993, after holding engineering positions at DTM Consulting and Syska and Hennessy Engineers, I was hired by Bill Sturgeon to come on board as the associate editor of Elevator World Magazine. This was something that in my wildest 1960s and '70s dreams I could never have imagined to be possible…but here it was. After working with—and being so significantly influenced by—the brightest minds in the elevator industry, I was now going to be working for another giant: Bill Sturgeon, one of the most intelligent men that I have ever encountered, and from whom I was to learn not only more about the elevator business but also about the publishing of magazines, books, and journals. And as he often said he would, Bill taught me “how to lead the orchestra!” “Being an editor,” Bill often stated, “is like being the conductor of an orchestra. A conductor strives to bring out the best in the musicians before him while taking little credit for doing so. Our job,” Bill used to say, “is to make those that write for ELEVATOR WORLD sound and look good, and this is the most satisfying job that anyone can have.” And he was right! I owe much to Bill Sturgeon, who not only taught me how to lead the band but also allowed and encouraged me to expand my horizons and learn from all of those that I encountered in my life.

When the time came for George Strakosch to update the third edition of The Vertical Transportation Handbook, he asked a number of us in the industry to assist him with this project by editing some of the chapters of the previous edition. George had spent years on the first two editions and had done more than the yeoman's share of the work; therefore at that time, for us, it was just a matter of editing and, where necessary, updating and expanding each of our sections.

It is often said that the hardest part of writing is completing the opening sentence, and anyone who writes regularly knows just how true this is. Well, George hadn't just given us opening sentences to work with but entire chapters, and 10 of us gratefully agreed to provide the needed assistance. Not only because we loved the elevator industry but also because, as does everyone who knows him, we loved George! He has always been there to help us and has always done so with an open heart and a smile on his face. This project was truly a labor of love for us all and one that was very satisfying as well.

Much gratitude for this work is also due to the following individuals, without whom the third and consequently this fourth edition of The Vertical Transportation Handbook would not have been possible.

Ed Donoghue, often referred to as “The Code God,” for his work throughout his career on elevator and escalator codes and standards and for the fine work he has done on the material on this subject.

George Gibson, the mechanical engineer extraordinaire in our industry, for his chapter updates on the mechanical design aspects of elevators in general and special-application elevators in particular.

Wayne Gilchrist, who, although he is no longer with us, is still one of my dearest friends. In my mind I turn to him often for guidance, as if he were still physically at my side…which sometimes I think he is. His previous work on the chapter “Automated Materials-Handling Systems” was so thorough for the third edition that it didn't need to be updated for this latest edition. Thanks, Wayne…!

Jon Halpern, our brilliant electrical engineering guru, who provided the updates on elevator operation and control.

Len LeVee, the nicest guy you ever want to meet and a fine elevator man, who did the previous work on the economics, maintenance, and modernization of elevator systems.

Joe Montesano, tough as nails when he needs to be, but with the heart and soul of a saint, who updated the chapter on elevator specifications and contracts.

Nick Montesano, my adopted brother, who loves everything elevators and most things escalators, always gets the job done, and does so with precision and thoroughness—and also brings more fun to the job than anyone could ever imagine. Nick took over the task of updating the chapter “Economics, Maintenance, and Modernization” from Len LeVee, who retired from the industry prior to our starting work on the fourth edition of this book.

Al Saxer, the elevator maintenance and modernization master, who pulled together the third-edition chapter “Service and Freight Elevators.”

Hank Peelle, another one of the nicest guys I know and an extraordinarily intelligent engineer, who, like the two generations before him, has dedicated his career to looking after the well-being of freight elevators and freight elevator doors. Hank updated Al Saxer's previous chapter on service elevators and added an extensive amount of new material to his section on freight elevators.

Davis Turner, whose brilliance is only surpassed by his sense (and often nonsense) of humor, who has been not only a tremendous help to me in my day-to-day work at Elevator World, but who is also an incredibly bright engineer, mathematician, and philosopher. Dave has looked after the escalator work in the third and fourth editions of this book, and we are forever grateful to him for his assistance and for his goofy sense of humor.

Jim Fortune, a true twenty-first-century visionary, who has not only traveled the world over but also designed the elevator systems in some of the world's most remarkable high-rise and super-tall buildings. Jim is a world-renowned expert on the conceptual analysis of super-tall buildings and their elevator systems. His additions to the chapter on the changing modes of vertical transportation reflect his involvement in this important aspect of our industry and his ability to remain on the cutting edge of elevator technology and building design.

Richard Peters, developer of elevator traffic analysis and simulation software, who has become a leading authority on the subject of elevator performance.

Bill Sturgeon is only listed following the others because his is the final chapter in the book. Bill has been my good friend for over 20 years and my mentor for over 15 years and has taught me not only a tremendous amount about the elevator industry from a trade publication editor's perspective but also so much about life in general. He has been an inspiration to me, and I can't thank him enough for all of the encouragement that he has given me, to always do the best that I can and to use all aspects of my conscious and subconscious mind to accomplish tasks. Thank you, Bill, for handing the ball off to me and not only letting me run with it but also constantly encouraging me to take it into the end zone.

This work could also not have been completed without the support of Elevator World's publisher, Ricia Hendrick, and the assistance of the magazine's special projects manager and research associate, Monica Tapper. Thank you, Ricia and Monica, for your support and help on this project.

And to George Strakosch I have to say that I have been truly blessed to have you in my life. Thanks for taking me under your wing and teaching me how to fly without getting in anyone's way. You showed me and so many others how to share knowledge and understanding with others and to always be there to provide inspiration and help to those around us. And for this I will be forever grateful. And a special thanks for having the confidence in me to let me assist you with this important elevator industry project.

And of course thanks to Mouse, who got me into this mess! Thanks, Big Guy.

ROBERT S. CAPORALE

Contributors

ROBERT CAPORALE, Editor

Elevator World Magazine

354 Morgan Avenue, P.O. Box 6507

Mobile, AL 36606

EDWARD A. DONOGHUE, Edward A. Donoghue Associates, Inc.

1677 County Route 64, P.O. Box 201

Salem, NY 12865-0201

JAMES FORTUNE, Fortune Consultants, Ltd.

2102 Mechanic Street

Galveston, TX 11788

GEORGE GIBSON, G. Gibson & Associates

555 Deer Pass Drive

Sedona, AZ 86351

WAYNE A. GILCHRIST, deceased, formerly of the Translogic Corporation

JON HALPERN, Jon B. Halpern & Associates, LLC

49 Hidden Ridge Drive

Syosset, NY 11791

LEN LEVEE, retired, formerly of Len Levee & Associates

JOSEPH MONTESANO, DTM Elevator Consulting

120-02 14th Road

College Point, NY 11356

NICHOLAS J. MONTESANO, DTM Elevator Consulting

120-02 14th Road

College Point, NY 11356

HANK PEELLE

The Peelle Company

373 Nesconset Highway

Hauppauge, NY 11788

DR. RICHARD PETERS, Peters Research Ltd.

Boundary House

Missenden Road

Great Kingshill, Bucks HP15 6EB, UK

AL SAXER, retired, formerly of Otis Elevator

38 Schoville Road

Avon, CT 06001

WILLIAM C. STURGEON, Founder and Editor Emeritus

Elevator World Magazine

354 Morgan Avenue, P.O. Box 6507

Mobile, AL 36606

DAVIS L. TURNER, Davis L. Turner & Associates

27615 Belmonte

Mission Viejo, CA 92692

1

The Essentials of Elevatoring

Early Beginnings

Since the time man has occupied more than one floor of a building, he has given consideration to some form of vertical movement. The earliest forms were, of course, ladders, stairways, animal-powered hoists, and manually driven windlasses. Ancient Roman ruins show signs of shaftways where some guided movable platform type of hoist was installed. Guides or vertical rails are a characteristic of every modern elevator. In Tibet, people are transported up mountains in baskets drawn by pulley and rope and driven by a windlass and manpower. An ingenious form of elevator, vintage about the eighteenth century, is shown in Figure 1.1 (note the guides for the one “manpower”). In the early part of the nineteenth century, steam-driven hoists made their appearance, primarily for the vertical transportation of material but occasionally for people. Results often were disastrous, because the rope was of fiber and there was no means to stop the conveyance if the rope broke.

Figure 1.1 A very early type of vertical transportation.

In the modern sense, an elevator1 is defined as a conveyance designed to lift people and/or material vertically. The conveyance should include a device to prevent it from falling in the event the lifting means or linkage fails. Elevators with such safety devices did not exist until 1853, when Elisha Graves Otis invented the elevator safety device. This device was designed to prevent the free fall of the lifting platform if the hoisting rope parted. Guided hoisting platforms were common at that time, and Otis equipped one with a safety device that operated by causing a pair of spring-loaded dogs to engage the cog design of the guide rails when the tension of the hoisting rope was released (see Figure 1.2).

Figure 1.2 (a) Otis's demonstration, Crystal Palace, New York, 1853. (b) Otis's patent sketch for a safety device (Courtesy Otis Elevator).

Elevator Safety Devices

Although Otis's invention of the safety device improved the safety of elevators, it was not until 1857 that public acceptance of the elevator began. In that year the first passenger elevator was installed in the store of E. V. Haughwout & Company in New York. This elevator traveled five floors at the then breathtaking speed of 40 fpm (0.20 mps).2 Public and architectural approval followed this introduction of the passenger elevator. Aiding the technical development of the elevator was the availability of improved wire rope and the rapid advances in steam motive power for hoisting. Spurring architectural development was an unprecedented demand for “downtown” space. The elevator, however, remained a slow vertical “cog” railway for quite a few years. The hydraulic elevator became the spur that made the upper floors of buildings more valuable through ease of access and egress. Taller buildings permitted the concentration of people of various disciplines in a single location and caused the cities to grow in their present form during the 1870s and 1880s.

Hydraulic Elevators

The hydraulic elevator provided a technological plateau for quite a few years; it was capable of higher rises and higher speeds than the steam-driven hoist-type elevator, limited by its winding drums (). The hydraulic elevator also evolved from the direct ram-driven elevator to the so-called geared or roped hydraulic () capable of speeds of up to 700 fpm (3.5 mps) and rises of 30 or more stories. The cylinder and sheave arrangement was developed to use multiple sheaves and was mounted vertically for the higher rises. The 30-story building did not appear until after 1900, well after steel-frame construction was introduced, but the hydraulic elevator served practically all of the 10- to 12-story buildings of the 1880 to 1900 era.