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American Water Works Association Errata to ANSI/AWA C560-O0 --``,``-`-`,,`,,`,`,,`---

Standard for

Cast-Iron Slide Gates (December 2002)

On page 9, in the footnote, the equation should be

P = Cn2 E A ( r l l ) 2

On page 16, in the footnote, “AWWA C501” should read “AWWA C560”.

On page 17, in the subtitle,”AWWA C501” should read “AWWA C560”.

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American Water Works Association ANSVAWWA C560-O0 (Revision of ANSVAWWA (2501-92)

AWWA STANDARD FOR

CAST-IRON SLIDE GATES -

~

i

œ

n

American NeUonai Standards Institute

AM ERICAN WATER WORKS ASSOCIATION 6666 West Quincy Avenue, Denver, Colorado 80235

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Effective date: Oct. 1, 2001. First edition approved by AWWA Board of Directors June 26, 1941. This edition approved June 11,2000. Approved by American National Standard Institute, July 25,2001.

A W A Standard This document is a n American Water Works Association (AWWA) standard. I t is not a specification. AWWA standards describe minimum requirements and do not contain all of the engineering and administrative information normally contained in specifications. The AWWA standards usually contain options that must be evaluated by the user of the standard. Until each optional feature is specified by the user, the product or service is not fully defined. AWWA publication of a standard does not constitute endorsement of any product or product type, nor does AWWA test, certify, or approve any product. The use of AWWA standards is entirely voluntary. AWWA standards are intended to represent a consensus of the water supply industry that the product described will provide satisfactory service. When AWWA revises or withdraws this standard, an official notice of action will be placed on the first page of the classified advertising section of Journal AWWA. The action becomes effective on the first day of the month following the month of Journal AWWA publication of the official notice.

American National Standard An American National Standard implies a consensus of those substantially concerned with its scope and provisions. An American National Standard is intended as a guide to aid the manufacturer, the consumer, and the general public. The existence of an American National Standard does not in any respect preclude anyone, whether that person has approved the standard or not, from manufacturing, marketing, purchasing, or using products, processes, or procedures not conforming to the standard. American National Standards are subject to periodic review, and users are cautioned to obtain the latest editions. Producers of goods made in conformity with an American National Standard are encouraged to state on their own responsibility in advertising and promotional materials o r on tags or labels that the goods are produced in conformity with particular American National Standards. CAUTIONNOTICE: The American National Standards Institute (ANSI)approval date on the front cover of this standard indicates completion of the ANSI approval process. This American National Standard may be revised or withdrawn at any time. ANSI procedures require that action be taken to reaffirm, revise, or withdraw this standard no later than five years from the date of publication. Purchasers of American National Standards may receive current information on all standards by calling or writing the American National Standards Institute, 11W. 42nd St., New York, NY 10036; (212) 642-4900.

All rights reserved. No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopy, recording, or any information or retrieval system, except in the form of brief excerpts or quotations for review purposes, without the written permission of the publisher.

Copyright O 2001 by American Water Works Association Printed in USA

11 --``,``-`-`,,`,,`,`,,`---

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Committee Personnel The AWWA Standards Committee on Slide Gates, which reviewed and approved

this standard, had the following personnel at the time of approval: Henry H. Benjes Jr., Chair

Consumer Members R.J.Alberts, City of Pasco, Pasco, Wash. Ronald Arrington, US Bureau of Reclamation, Denver, Colo. K.D. Jones, City of Midland, Midland, Texas H.C. Suan, Edmonton Public Works, Edmonton, Ont.

General Interest Members C.S. Barger, Bloomington, Minn.

(AWWA)

H.H. Benjes Jr., HDR Inc., Austin, Texas

(AWWA)

Aivars Bergs, R.V. Anderson Associates Ltd., Willowdale, Ont.

(AWWA)

J.H. Cook, Carter & Burgess Inc., Fort Worth, Texas

(AWWA)

C.R. Dugan, Council Liaison, Board of Water and Light, Lansing, Mich.

(AMA)

P.J. Olson,* Standards Engineer Liaison, AWWA, Denver, Colo.

(AWWA)

Prod ucer Members P.E. Brunelle, Rodney Hunt Company, Orange, Mass. Carl Ingimundson, Armtec Water Control Products, Guelph, Ont. M.J. McCaig, Misco Rocky Mountain, Denver, Colo. G.M. Tuttle, Waterman Industries Inc., Exeter, Calif.

*Liaison, nonvoting

...

111 --``,``-`-`,,`,,`,`,,`---

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Contents All AWWA standards follow the general format indicated subsequently. S o m variations from this format may be found in a particular standard. PAGE

SEC.

PAGE

SEC.

Foreword

4

Requirements

I

Introduction ........................................ vii

4.1

Data to Be Provided by the Supplier.. 4

I.A

Background.........................................

vii

4.2

Data to Be Provided by the

1.B

History ................................................

vii

1.c

Acceptance ..........................................

vii

II

Special Issues ......................................

III

Use of This Standard ..........................

ix ix

1II.A

Purchaser Options and Alternatives. ix

1II.B

Modification to Standard .....................

x

IV

Major Revisions....................................

x

V

Comments .............................................

x

Manufacturer ....................................

4

4.3

Materials ...............................................

4

4.4

General Design .....................................

6

4.5

Manufacture........................................ 13

4.6

Installation and Field Testing ........... 14

5

Verification

5.1

Inspection .......... ........... ....................... 15

5.2

Test Procedures ..................................

6

Delivery

6.1

Marking ...............................................

16

6.2

Shipment .............................................

16

6.3

Affidavit of Compliance......................

16

Standard 1

General

1.1

Scope .....................................................

1

1.2

Purpose .................................................

1

1.3

Application ............................................

1

2

References ..........................................

2

3

Definitions..........................................

3

Appendix

A

Force Required to Actuate Cast-Iron Slide Gate ........................................

V

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16

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17

Foreword This foreword is for information only and is not a part of AWWA C560.

I. Introduction. I.A. Background. A cast-iron slide gate is a cast-iron, vertically sliding valve with metal (usually bronze or stainless steel) seating surfaces and adjustable metal (usually bronze or stainless steel) wedges. A slide gate is used at the end of a pipeline

or t o cover an opening in a wall. It is not an in-line valve. Slide gates are raised and lowered by means of a stem or rod using a manually operated screw stem hoist, an electrically driven screw stem hoist, or a hydraulic cylinder. Slide gates are mounted to a pipe flange, to a wall casting or thimble embedded in the concrete, or directly to the concrete wall with anchor bolts. I.B. History. The original AWWA standard for slide gates was approved as tentative in June 1941 and was referred to as sluice gates. The tentative standard was revised and approved in 1967 as AWWA Standard (3501. Revisions t o AWWA C501 include the following: Designation

Date of Approval

AWWA C501-41T

June 26, 1941

AWWA (3501-67

June 4, 1967

AWWA (2501-80

Jan. 28, 1980

AWWA C501-87

June 14, 1987

A W A C501-92

June 18, 1992

This edition of C560-O0was approved on June 11,2000. I.C. Acceptance. In May 1985, the US Environmental Protection Agency

(USEPA) entered into a cooperative agreement with a consortium led by NSF International (NSF) to develop voluntary third-party consensus standards and a certification program for all direct and indirect drinking water additives. Other Research Foundation (AWWARF) and the Conference of State Health and Environmental Managers (COSHEM). The American Water Works Association (AWWA) and the Association of State Drinking Water Administrators (ASDWA)joined later.

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members of the original consortium included the American Water Works Association

In the United States, authority to regulate products for use in, or in contact with, drinking water rests with individual states.* Local agencies may choose to impose requirements more stringent than those required by the state. To evaluate the health effects of products and drinking water additives from such products, state and local agencies may use various references, including

1. An advisory program formerly administered by USEPA, Office of Drinking Water, discontinued on Apr. 7, 1990.

2. Specific policies of the state or local agency. 3. Two standards developed under the direction of NSF, ANSIt/NSFS 60, Drinking Water Treatment Chemicals-Health Water System Components-Health 4.

Effects, and ANSVNSF 61, Drinking

Effects.

Other references, including AWWA standards, Food Chemicals Codex,

Water Chemicals Codex,§ and other standards considered appropriate by the state or local agency. Various certification organizations may be involved in certiS.ing products in accordance with ANSVNSF 61. Individual states or local agencies have authority t o accept or accredit certification organizations within their jurisdiction. Accreditation Annex A, “Toxicology Review and Evaluation Procedures,” to ANSUNSF 61 does not stipulate a maximum allowable level (MAL) of a contaminant for substances not regulated by a USEPA final maximum contaminant level (MCL). The MALS of an unspecified list of “unregulated contaminants” are based on toxicity testing guidelines (noncarcinogens) and risk characterization methodology (carcinogens). Use of Annex A procedures may not always be identical, depending on the certifier. AWWA (2560 does not address additives requirements. Thus, users of this standard should consult the appropriate state or local agency having jurisdiction in order to

1. Determine additives requirements including applicable standards.

*Persons in Canada, Mexico, and non-North American countries should contact the appropriate authority having jurisdiction. ?American National Standards Institute, 11 W. 42nd St., New York,NY 10036. SNSF International, 789 N. Dixboro Rd., Ann Arbor, MI 48105.

0 Both publications available from National Academy N.W., Washington, DC 20418.

...

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of Sciences, 2102 Constitution Ave.

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of certification organizations may vary from jurisdiction to jurisdiction.

2. Determine the status of certifications by all parties offering to certify products for contact with, or treatment of, drinking water.

3. Determine current information on product certification.

II. Special Issues. This standard has no applicable information for this section.

III. Use of This Standard. AWWA has no responsibility for the suitability user. Accordingly, each user of this standard is responsible for determining that the standard's provisions are suitable for and compatible with that user's intended application. 1II.A. Purchaser Options and Alternatives. The following items should be covered in the purchaser's specifications:

1. Standard used-that

is, AWWA C560,Standard for Cast-Iron Slide Gates

of latest revision.

2. Number of units required. 3. Size and type of closure-conventional or flush-bottom. 4. Any drawings and material specifications required of the supplier or of the manufacturer (Sec. 4.1and 4.2). 5. If test records must be viewed (Sec. 4.3.2).

6. Acceptable materials (Sec. 4.3.3).

7. Design head measured from surface of water to centerline of gate, in feet (metres), for the following:

a. Seating head. b. Unseating head. 8. Operating head measured from surface of water to centerline of gate, in feet (metres). 9. Length and shape of wall thimble or connecting device (Sec. 4.4.10).

10. Rising stem or nonrising stem (Sec. 4.4.7and 4.4.11). electric-motor-driven, or hydraulic-cylin-

11. Type of lift mechanism-manual,

der. If electric-motor-driven or hydraulic-cylinder, the purchaser should refer to ANSYAWWA (3540.

12. If an actuator stand is needed (Sec. 4.4.14).

13. If hydraulic or pneumatic actuators are specified, provide cylinder operating media and pressure (refer to ANSYAWWA C540,Standard for Power-Actuating Devices for Valves and Slide Gates).

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or compatibility of the provisions of this standard t o any intended application by any

14. Omission of stem covers (Sec. 4.4.14.6), if not required. 15. Leakage tests in the shop (Sec. 4.5.2.2)and in the field (Sec. 4.68,if required.

16. Inspection by purchaser, if required (Sec. 5.1). 17. Separate shipment of embedded items (Sec. 6.2). 18. Affidavit of compliance (Sec. 6.31,if required.

19. Definition of any special design and construction required for conditions beyond the scope of this standard, such as throttling service or downward acting gates, including intended operation frequency and duration. 20. Frequency of operation and special operating conditions, such as ice formation.

21. An installation-requirement drawing showing clearances, wall and floor thicknesses, details of wall pipe and thimble installation, and location of operator. 1II.B. Modification to Standard. Any modification t o the provisions, definitions, or terminology in this standard must be provided in the purchaser’s specifications.

IV. Major Revisions. Major revisions made t o the standard in this revision include the following:

1. Definitions for design and operating heads have been added (Sec. 3). 2. Material requirements for stem couplings and thrust nut and gate-actuator lift nuts have been added (Sec. 4.3.3.6and 4.3.3.7).

3. Sec. 4.4.11Stems and Stem Couplings has been revised.

4. Sec. 4.4.14Manual Lifting Devices has been revised.

5. Sec. 4.4.15Powered Lifting Devices has been added.

V. Comments. If you have any comments or questions about this standard, please call the AWWA Volunteer and Technical Support Group, (303)794-7711ext.

6283,FAX (303)795-7603,or write to the group at 6666 W. Quincy Ave., Denver, CO --``,``-`-`,,`,,`,`,,`---

80235.

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American Water Works Association

A N S V A W A C560-O0 (Revision of ANSVAWWA C501-92)

AWWA STANDARD FOR

CAST-IRON SLIDE GATES SECTION 1: GENERAL Sec. 1.1 Scope This standard describes vertically mounted, cast-iron slide gates designed for either seating head o r unseating head, or both, in ordinary water-supply service. The cast-iron slide gates have machined metal faces and machined adjustable wedging devices. The cast-iron slide gates may be used for square, rectangular, or round openings. They may be of the conventional-closure or the flush-bottom-closure type. This standard also describes manual slide gate actuator mechanisms together with standard accessories. Other actuator mechanisms, including electric or hydraulic mechanisms, are described in ANSI/AWWA C540 with an exception noted in

Sec. 4.4.15 of this standard.

Sec. 1.2 Purpose --``,``-`-`,,`,,`,`,,`---

The purpose of this standard is to provide the minimum requirements for castiron slide gates, including materials, general design, manufacture, testing, inspection, and shipment.

Sec. 1.3 Application This standard can be referenced in specifications for purchasing and receiving cast-iron slide gates and can be used as a guide for designing and manufacturing cast-iron slide gates. The stipulations of this standard apply when this document has been referenced and then only to cast-iron slide gates used in water supply service application.

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2 AWWAC560-O0

SECTION 2: REFERENCES This standard references the following documents. In their latest editions, they form a part of this standard to the extent specified within the standard. In any case of conflict, the requirements of this standard shall prevail. AISI* 1 1 1 7 4 t a n d a r d for Resulfured Carbon Steel. AISI 4140-Standard

for Alloy Steel.

AISI 8620-Standard

for Alloy Steel.

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ANSI? ASMES B16.1-Standard

for Cast Iron Pipe Flanges and Flanged

Fittings, Class 25, 125,250 and 800. ANSYASME B46.l-Standard

for Surface Texture (Surface Roughness, Wavi-

ness, and Lay). ANSVASTM D47l-Standard

Test Method for Rubber Property-Effect

of

Liquids. ANSYAWWA C540-Standard

for Power-Actuating Devices for Valves and Slide

Gates. ASTMPA36íA36M-Standard ASTM A48-Standard ASTM A126-Standard

Specification for Carbon Structural Steel.

Specification for Gray Iron Castings. Specification for Gray Iron Castings for Valves, Flanges,

and Pipe Fittings. ASTM A276-Standard

Specification for Stainless Steel Bars and Shapes.

ASTM A582/A582M-Standard

-

Specification for Free-Machining Stainless Steel

Bars, Hot-Rolled or Cold-Finished. ASTM B21-Standard ASTM B98-Standard

Specification for Naval Brass Rod, Bar, and Shapes. Specification for Copper-Silicon Alloy Rod, Bar, and

Shapes.

ASTM B138-Standax-d Specification for Manganese Bronze Rod, Bar, and Shapes.

*American Iron & Steel Institute, 1101 17th Street N.W., Washington, DC 20036. TAmerican National Standards Institute, 11W.42nd St., New York, NY 10036. $American Society of Mechanical Engineers, 345 E. 47th Ave., New York, NY 10017. §American Society for Testing and Materials, 100 Barr Harbor Dr., West Conshohocken, PA 19428-2959.

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CAST-IRON SLIDE GATES 3

ASTM B139B139M-Standard

Specification for Phosphor Bronze Rod, Bar, and

Shapes.

ASTM B 148-Standard Specification for Aluminum-Bronze Sand Castings. ASTM B5OWtandard Specification for Copper-Base Alloy Continuous Castings. ASTM B58A-Standard Specification for Copper Alloy Sand Castings for General Applications. ASTM Dll49-Standard

Test Method for Rubber Deterioration-Surface Ozone

Cracking in a Chamber. ASTM D2000-Standard Classification System for Rubber Products in Automotive Applications. ASTM F593-Standard

Specification for Stainless Steel Bolts, Hex Cap Screws,

and Studs. ASTM F594-Standard Specification for Stainless Steel Nuts. CDA* Copper Alloy Numbers. (NOTE:CA precedes alloy numbers defined by

CDA.) SSPCp SPG-Commercial Blast Cleaning.

O

SECTION 3: DEFINITIONS The following definitions shall apply in this standard:

Design head: Design head (seating or unseating) is the maximum

1.

differential head that will actually be applied to the gate under worse-case conditions.

2.

Manufacturer: The party that manufactures, fabricates, or produces

materials or products.

3. Operating head: Operating head is the highest differential head on the gate when it must be operated. 4.

Purchaser: The person, company, or organization that purchases any

materials or work to be performed.

*Copper Development Association, Greenwich Office Park 2, P.O. Box 1840, Greenwich, CT 06836-1840.

t Society for Protective Coatings, 40 24th Street, Sixth Floor, Pittsburgh, PA 15222-4656.

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SSPC SP10-Near-White Blast Cleaning.

4 AWWAC560-O0

5 . Supplier: The party that supplies material or services. A supplier may or may not be the manufacturer.

SECTION 4:

REQUIREMENTS

Sec. 4.1 Data to Be Provided by the Supplier When required, the supplier shall provide certified drawings and material specifications of the equipment to be supplied according to the provisions of this standard. The drawings shall be in sufficient detail for the purchaser to determine if the proposed equipment meets the specifications. The drawings shall show the dimensions of the gate opening.

Sec. 4.2 Data to Be Provided by the Manufacturer When required, the manufacturer shall submit, for acceptance by the purchaser, certified drawings showing the principal dimensions, general construction, and materials used for all parts of the slide gate and lift mechanism. All slide gates shall be manufactured and provided in accordance with these drawings after they have been accepted by the purchaser. The manufacturer shall also provide illustrated catalog data and parts schedules in sufficient detail to serve as a guide for assembly and disassembly of the gate and for ordering repair parts.

Sec. 4.3 Materials 4.3.1 Physical and chemical properties. The requirements of all AWWA,

ANSI, ASTM, CDA, or other standards referenced in this text shall govern the physical and chemical characteristics of the slide gate components. 4.3.2 Tests. Whenever slide gate components are to be made in conformance requirements or procedures shall be met by the manufacturer. "he records of these tests shall be made available if required by the purchaser. 4.3.3 Requirements. All materials designated in this standard, when used in slide gates produced according to this standard, shall conform to the requirements of the standards designated for each material listed. When reference is made t o any AWWA,

ANSI, ASTM,

CDA, or other standard, the latest revision of the standard

shall apply.

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with industry standards that include test requirements or testing procedures, these

CAST-IRON SLIDE GATES 5

Materials shall conform to the following specifications: 4.3.3.1 Thimble, frame, guides, slide, stem guides, and gear housing: Cast iron-ASTM

A126, class B; or ASTM A48, class 30.

4.3.3.2 Yoke and pedestal: Cast iron-ASTM class 30; or steel-ASTM

A126, class B; or ASTM A48,

A36.

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4.3.3.3 Gears: Steel-AIS1

8620, AISI 4140, or AISI 1117; bronze-ASTM

B148 (CA 952, CA 954, or CA 958), ASTM B584 (CA 865 or CA 867). 4.3.3.4 Bearings: Bronze-ASTM 4.3.3.5

Wedges: Bronze-ASTM

B148 (CA 954). B584 (CA 836,* CA 865,* CA 863,* or CA 873).

4.3.3.6 Stem Couplings: Bronze-ASTM B584 (CA 865,* CA 863,* or CA 873); stainless steel-ASTM

A582, type 303; or ASTM A276, type 302 or 304.

4.3.3.7 Thrust nut and gate actuator lift n u t Bronze-ASTM B584 (CA 865,* CA 863,* or CA 873), ASTM B505 (C95800). 4.3.3.8 Seating faces and stem guide: Bronze-ASTM

B21 (CA 464 or

CA482),* ASTM B138 (CA 675),* ASTM B98 (CA 651 or CA 655), ASTM B139 (CA 510); or ASTM B584 (CA 836, CA 865, CA 863 or CA 873); stainless steel-ASTM A276, type 302 o r 304. 4.3.3.9 Stem guide bushings: Bronze-ASTM

B584 (CA 932 or CA 873),

ASTM B98 (CA 651 or CA 653, or ASTM B139 (CA 510). 4.3.3.10 Stems: Stainless steel-ASTM

A582, type 303; or ASTM A276, type

302 or 304. 4.3.3.11 Anchor bolts and fasteners:

Stainless steel-ASTM

ASTM F594, alloy group 1 or group 2; or bronze-ASTM

B98 (CA 651 or CA 655).

4.3.3.12 Flush-bottom seal: Elastomeric materials-ASTM 4.3.3.13 Flush-bottom retainer bar: Cast iron-ASTM steel-ASTM

F593 o r

D2000.

A126, class B; stainless

A276, type 302 or 304; ASTM A582, type 303; bronze-ASTM

B98

(CA 651 or CA 655); or ASTM B138 (CA 675)*.

*Some materials described in the cited documents are subject to dealuminization o r dezincification in some waters. In the absence of specific provisions by the purchaser, any material listed above shall be acceptable. However, it is recommended that the purchaser prohibit the use of the materials identified as being subject to dezincification o r dealuminization unless experience has shown that dezincificationor dealuminization has not been a problem.

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6 AWWAC560-O0

Sec. 4.4 General Design 4.4.1 Frames. 4.4.1.1 Material. The frame shall be made of cast iron. It shall be of ample

O

section and cast in one piece.

4.4.1.2 Design. The frame shall be designed for the design head indicated

4

with a minimum safety factor of 5 with regard to tensile, compressive, and shear strength. All surfaces forming joints or bearings shall be machined. The frame shall

i

be machined on the rear face to bolt directly to the machined face of the wall thimble.

4.4.2 Slides. 4.4.2.1 Material. The slide shall be made of cast iron, with strengthening ribs where required and a reinforced section to receive the seating faces.

4.4.2.2 Design. The slide shall be designed for the design head indicated with a minimum safety factor of 5 with regard to tensile, compressive, and shear strength. The slide shall have tongues on each side extending the full length of the slide. The tongues shall be machined accurately on contact surfaces. Surfaces of the slide that come into contact with the seat facings and wedges shall be machined accurately. The maximum allowable clearance between the slide and the slide guide shall be

l/16

in.

(1.6mrn*). A thrust-nut pocket shall be provided above the horizontal centerline of 4.4.3 Seating faces. 4.4.3.1 Material. Seating faces shall be made of strips of rolled or extruded bronze or stainless steel. They shall be secured firmly in finished grooves in the frame and slide faces s o as t o ensure that they will remain in place, free from distortion and loosening, during the life of the slide gate.

4.4.3.2 Clearance. The seating faces shall be of ample cross section and ñnished so that the maximum clearance between the seating surfaces, with the slide in the closed position, shall be 0.004in. (0.102 mm).

4.4.4 Seals. 4.4.4.1 Material. Resilient seals for flush-bottom gates shall be extruded or molded natural or synthetic rubber. Reclaimed rubber shall not be used.

4.4.4.2 Design. The seal shall be designed t o provide for the minimum leakage as specified in Sec. 4.6.8.Seals shall be mounted on the slide or the frame

*Metric conversions given in this standard are direct conversions of US customary units and are not those specified in International Organization for Standardization (ISO) standards.

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O --``,``-`-`,,`,,`,`,,`---

the slide. The thrust-nut pocket shall be reinforced by ribs and drained.

CAST-IRON SLIDE GATES 7

and shall be held securely in place with a retainer bar bolted to the frame or slide, leaving an unobstructed flush invert. 4.4.4.3

Material tests. Rubber compounds shall be capable of withstanding

an ozone-resistance test when tested in accordance with ASTM D1149. The tests shall be conducted on unstressed samples for 70 hr at 104°F (40°C) without visible cracking in the surfaces of the test samples after the tests. Rubber compounds shall have less than 2 percent volume increase when tested in accordance with ANSI/ ASTM D471, after being immersed in distilled water at 73.4"F *2"F (23°C d o c )for 70 hr. 4.4.5 Guides. 4.4.5.1 Material. Guides shall be made of cast iron and bolted to the frame or cast integrally with it. Guides shall be machined on all bearing and contact faces. 4.4.5.2 Design. Guides shall be designed for the design head indicated with a safety factor of 5 for shear, compressive, and tensile strength. The guides shall be of such length as t o support at least one-half the vertical height of the slide when the slide is in the open position. Provisions shall be made to prevent lateral movement of bolted-on guides. They shall be capable of taking the entire thrust produced by water pressure and wedging action with a safety factor of 5 . Wedges or wedge facings shall be attached securely t o the guides at points where, in the closed position, they will make full contact with the wedging surfaces on the slide. The guides of self-contained gates shall be provided with pads for mounting the yoke. The pads shall be machined

t o a plane perpendicular to the movement of the gate slide. Self-contained gates shall be provided with a cast-iron or

structural-steel yoke designed to withstand the thrust of the floorstand or hoist when a 40-lb (178-N) effort is placed on the handwheel or crank with a safety factor of 5

based on the ultimate strength of the material used. The top of the yoke shall be machined to receive the operating mechanism. The pads on the yoke that contact those on the top of the guides shall be machined on contact faces and bolted to the guides. 4.4.7 Thrust nut. Each gate shall be provided with a thrust nut for connecting the stem to the slide. It shall be of ample design to withstand the thrust developed when a 40-lb (178-N) effort is placed on the handwheel or crank with a safety factor of 5 based on the ultimate strength of the material used. The thrust nut and slide shall be constructed to prevent turning of the thrust nut in the thrust-nut pocket in the slide. On rising-stem gates, the thrust nut shall be threaded and keyed

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4.4.6 Yoke.

8 AWWAC560-O0

or threaded and pinned to the stem. On nonrising-stem gates, the thrust nut shall be

threaded but not keyed or pinned t o the stem, so that the nut and slide can move up and down the stem as the stem turns.

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4.4.8 Wedging devices. All slide gates shall be equipped with adjustable side-wedging devices t o provide contact between the slide and fi-ame facings when the gate is in the closed position. All faces shall be machined accurately to give maximum ~

contact and wedging action. Wedges shall be fully adjustable and designed so that they will remain in the fixed position after adjustment. On all conventional closure gates wider than 24 in. (600 mm) that will be subjected t o unseating heads, top and bottom wedging devices shall be provided. Flush-bottom closure gates wider than

24 in. (600 mm) that will be subjected t o unseating heads shall be provided with top wedges.

4.4.9 Assembly bolts, studs, nuts, and anchor bolts.

All

assembly bolts,

studs, nuts, and anchor bolts shall be of a size and spacing as required t o provide for the design forces with a safety factor of 5 based on the ultimate strength of the material used. Bolting on circular flanged-back gates mounting to pipe flanges shall mate with class 25-lb (172-kPa) or class 125-lb (861-”a)

drilling as specified in

ANSVASME B16.1. For gates mounting t o thimbles, an adequate number of holes shall be provided in the flange on the back of the gate to prevent leakage under the design heads and t o resist the shearing action caused by closing and opening forces.

4.4.10 Wall thimbles. 4.4.10.1 Material. The wall thimble shall be made of cast iron and shall be provided by the gate manufacturer. The wall thimble shall provide a rigid mounting designed to prevent warping of the gate frame during installation.

4.4.10.2 Design. The cross section of the thimble shall be a pipe flange or shall be F-shaped or E-shaped with a suitable end for attaching to the connecting pipe. The front, or mounting flange, shall be machined and shall be drilled and tapped t o the same template used for its particular gate frame. A ring shall be cast on the periphery of the wall thimble to form a water stop and anchor ring in the concrete. The gate shall be attached to the wall thimble with bolts or studs as specified in Sec. 4.4.9.

4.4.10.3 Release of air. To permit entrapped air to escape as the thimble is being encased in concrete, holes shall be cast or drilled in each entrapment zone formed by the reinforcing ribs, flanges, and water stops. The holes shall be

(38 mm) in diameter and no more than 2 ft (600 mm) apart.

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IV2

in.

CAST-IRON SLIDE GATES 9

4.4.11 Stems und stern couplings. 4.4.11.1 Material. The stem shall be solid stainless steel. 4.4.11.2 Design. The operating stem shall be designed to withstand a manual actuator (or electric motor actuator in manual mode) tension load caused by the application of a 40-lb (178-N) effort on the crank or handwheel or a 50-ft-lb (68-N-m) torque on a wrench nut without exceeding one fifth of the ultimate tensile strength of the stem material. In compression, the operating stem shall be designed for a critical buckling compressive load assuming a 40-lb (178-N) effort on the crank or handwheel

or a 50-ft-lb (68-N-m) torque on a wrench nut with a safety factor of 2. The critical buckling load shall be determined by using the Euler Column formula,*where C = 2. Where hydraulic-cylinder lifts are used, the stem design force shall not be less than 1.25 times the output thrust of the hydraulic cylinder with a pressure equal to the maximum working pressure (not pressure relief valve setting) of the hydraulic fluid supply. Where electric-motor-driven actuators are used, the stem design force shall not be less than 1.25 times the output thrust of the unit in the stalled-motor condition. 4.4.11.3 Threads. Stem threads shall be machine cut or rolled and of the American Standard general purpose acme or stubacme type. The thread spacing shall be selected to work effectively with the lift mechanism used. On rising-stem gates with manual hoists, the top of the stem shall be provided with a stop collar t o be field adjusted according to the manufacturer’s instructions at the time of gate installation

to prevent over-closing of the gate. 4.4.11.4 Coupling. Where stems are provided in more than one piece, the different sections shall be joined together by solid couplings. The couplings shall be threaded and keyed or threaded and bolted and shall be of greater strength than the stem. 4.4.11.5 Inverted gates.

For all inverted-gate applications where the gate is

lowered t o open, a stop collar or other positive means shall be provided to prevent the loss of the slide from the guides. 4.4.12 Stem guides.

Bracket and floor-mounted stem guides (including both

the guide housing and the bracket) shall be constructed so that when properly

*Euler Column formula: P = Cxt2EA (rIO2, where P = axial load on stem, C defines end restraint conditions,E = modulus of elasticity, I = length or span between supports, r = radius of gyration, and A = area of stem.

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10 AWWA C560-O0

spaced, they will hold the stem in alignment and yet allow it enough play to permit easy operation. The inside diameter of the guide shall not be greater than ?/a in. (3 mm) larger than the outside diameter of the stem. The guides shall be spaced according to the manufacturer?s recommendations for each stem size. The length/ radius of gyration ratio (Zlr) shall not be greater than 200. The guides shall be adjustable relative t o the bracket. The bracket shall be adjustable relative to the wall to provide proper concentric alignment with the stem and shall be designed so that alignment will be maintained after adjustment. The guides shall be lined, and provisions shall be made t o hold the lining in place. Brackets shall be attached to the wall by anchor bolts sufficient t o prevent twisting or sagging under load. 4.4.13 Painting. 4.4.13.1 Cleaning and preparation.

Surfaces subject to submergence shall be

cleaned to SSPC SP10, dry and free from grease before painting in conformance with the paint manufacturer?s instructions. Other surfaces shall be cleaned to SSPC SP6, dry and free from grease before painting in conformance with the paint manufacturer?s instructions. After cleaning, the surfaces shall be primed and finish-coated in the rnanufact~rer~s shop with a high-solids epoxy coating or equivalent suitable for use in potable water. After painted surfaces are dry, the machined o r bearing surfaces and the holes, both plain and threaded, shall be coated with a protective grease until time of installation. 4.4.13.2 Thimble. The wall thimble shall have the same treatment described in Sec. 4.4.13.1, except for those surfaces in contact with concrete, which shall remain uncoated. 4.4.14 Manual lifting devices. 4.4.14.1 Operation. The manual lift mechanism shall have either a direct drive handwheel without reduction gearing, or shall be crank-actuated with either single- or double-reduction gearing, as necessary to meet lifting capacity required. The lift mechanism shall be sized to permit slide operation with an effort of not more than 40-lb (178-N) pull on the handwheernandcrank or 50-fi-lb (68-N-m) torque on the lift nut or input shaft, depending on the lift type. Maximum pull or torque t o start the slide in motion must not exceed one and one-half times this amount. All components of the lift mechanism shall be designed to withstand these input efforts

or torques with a minimum safety factor of 5 with regard to tensile, compressive, and shear strength.

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CAST-IRON SLIDE GATES

11

4.4.14.2 General design. The lift mechanism shall have a bronze lift nut threaded t o fit the operating stem. Tapered roller or ball thrust bearings shall be provided above and below the flange on the lift nut to take the thrust developed during gate operation. All bearings (and gears) shall be enclosed in a cast iron housing with oil seals and O-rings or mechanical seals used t o seal the unit. Fittings shall be provided so that all bearings (and gears) can be periodically lubricated. The

lift mechanism shall be supplied with a pedestal, torque tube, o r baseplate, machined and drilled for mounting the lift housing and ready for bolting to the operating floor, top wall mounting bracket, or gate yoke, as required.

4.4.14.3 Gear reduced lifts. The drive gears used in gear reduction lifts shall be made of steel and accurately machined, with cut teeth to provide smooth and proper operation. Input shafts shall be made of stainless steel and supported by tapered rollers o r other roller-type bearings designed to withstand the radial and thrust loads generated during operation. All geared lifts shall be suitable for operation using a portable motor apparatus.

4.4.14.4 Crankhandwheel. The crank shall be removable and fitted with a corrosion-resistant rotating handle. The maximum crank radius shall be 15 in.

(380mm), and the maximum handwheel diameter shall be 30 in. (760 mm). 4.4.14.5 Opening direction. The direction of wheel or crank rotation to open the gate shall be indicated on the lift mechanism. Single-speed actuators shall open counterclockwise. Two-speed actuators shall open counterclockwise for low mechanical-advantage gear ratio and open clockwise at the high mechanical-advantage gear ratio.

4.4.14.6 Stem cover. Each rising-stem unit shall be provided with a stem cover unless otherwise specified by the purchaser. The cover shall be made of galvanized steel pipe, or aluminum pipe, or a clear plastic pipe that will not discolor, crack, or become opaque for at least five years after installation. Slotted metal stem covers used to indicate a position shall have clear plastic windows. The cover shall be of sufficient diameter and length to permit full travel of the threaded stem without obstruction. The top of the stem cover shall be closed. The bottom end of the stem cover shall be vented, drained, and mounted in a housing or adapter plate for easy field mounting installation.

4.4.14.7 Indicator. Each actuator for rising-stem gates with a solid galvanized steel or aluminum pipe cover and all actuators for nonrising-stem gates shall be

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12 A W A C560-O0

provided with a dial or counter type position indicator to show the position of the gate at all times. The indicator shall be geared to the lift mechanism.

4.4.14.8 Dual actuators. All gates 48 in. (1,200 mm) and wider and having

O

widths greater than twice their height shall be provided with two lifting devices connected by a tandem shaft for simultaneous operation. Cross shafting shall be stainless steel. Flexible couplings shall be provided at each end of the cross shaftings.

4.4.14.9 Surface preparation. Surfaces shall be prepared in accordance with Sec. 4.4.13.1 and shall have a high-solids epoxy protective coating or equivalent applied. Coating does not have to be suitable for potable water unless the actuator is immersed.

4.4.15 Powered Lifting Devices 4.4.15.1 Speed of operation. The power actuator shall be designed to move the gate slide at a rate of 10-14 in./min (254-356 m d m i n ) under specified operating head conditions.

4.4.15.2 Finish. 1. Cleaning and preparation. Surfaces shall be prepared in accordance with Sec. 4.4.13.1.

2. Submerged surfaces or surfaces subjected to splashing. After cleaning, these surfaces shall be primed and finish-coated in the manufacturer’s shop with a

O

minimum two-coat high-solids epoxy coating or equivalent suitable for use in potable water. After painted surfaces are dry, all machined or bearing surfaces and the holes, both plain and threaded, shall be coated with a protective grease suitable for potable water until time of installation.

3. Exposed above-grade surfaces. After cleaning, these surfaces shall be primed and finish-coated in the manufacturer’s shop with a high-solids epoxy protective coating or equivalent suitable for outdoor exposure. The coating does not have to be suitable for potable water.

4.4.15.3 Electric motor actuators. Electric motor actuators shall be per ANSI/

AWWA (3540, Sec. 3, except as follows: 1. When in the handwheel mode of operation, the handwheel shall require a maximum 40-lb (178-N) pull on the handwheel or a 50-ft-lb (68-N-m) torque on the input shaft to operate the gate. Maximum pull or torque to start the slide in motion may not exceed one and one-half times this amount.

2. A mechanical dial position indicator will be required only for operators supplied with metal stem covers or when used on nonrising stem gates.

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CAST-IRON SLIDE GATES

13

4.4.15.4 Cylinder actuators. Cylinder actuators shall be in accordance with

ANSVAWWA C540, Sec. 4, with the exception of piston rods. All piston rods shall be 30,000 psi (206.8 MPa) minimum yield strength, type 303 or 304 stainless steel, hard chrome plated, 0.0005-in. (0.0127-mm)thick, and shall have a 20-micro-in. (0.000508mm) finish or smoother.

Sec. 4.5 Manufacture 4.5.1 Workmanship. All parts in the slide gate and accessories shall be machined accurately on mating and bearing surfaces. All like parts, except for the bronze seating surfaces, shall be interchangeable so that replacement parts can be provided at any time and attached in the field with a minimum of fitting, chipping,

or remachining. All parts shall conform t o the design dimensions and shall be free from defects in material and workmanship. All attaching bolt holes shall be drilled accurately to layout indicated on the drawings. 4.5.1.1 Castings. All castings shall be clean, sound, and without defects that could impair their function. 4.5.1.2 Seating finish. "he seating facings shall be machined to a finish of 63 micro in. (0.0016 mm) in conformance with ANSVASME B46.1. All mating surfaces, such as guides-to-frame and frame-to-wall thimble, shall be machined flat. 4.5.2 Shop testing. 4.5.2.1 Seat clearance check. Before final assembly, all seating and wedging surfaces shall be cleaned thoroughly of all foreign materials and final adjustments --``,``-`-`,,`,,`,`,,`---

made. With the gate fully closed, the clearance between seating faces shall be checked with a 0.004-in. (0.102-mm) thickness gauge. If the thickness gauge can be inserted between seating faces, the wedging devices shall be readjusted, or the gate slide or gate frame, or both, shall be remachined until insertion is no longer possible. In the event of remachining, clearances shall be checked again as stated above. 4.5.2.2 Performance tests. After completion, all seating and wedging surfaces shall be cleaned thoroughly of all foreign materials and final adjustments shall be made. "he slide gate shall then be shop-operated from the fully closed to the fully open positions to verify that the assembly is workable. A shop leakage test, meeting the requirements of Sec. 4.6.8, shall be made when specified in the purchaser's specifications.

NOTE: Shop leakage tests cannot be carried out for all types and sizes of gates. Purchasers should consult the manufacturers involved before specifying these tests.

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14 AWWA C560-O0

Sec. 4.6 Installation and Field Testing It shall be the purchaser’s responsibility to handle, store, and install the wall thimble or other connection device, gate, actuator mechanism, stem, stem guides, and accessories in accordance with the manufacturer’s drawings and recommendations. Warping the gate frame shall be avoided, and tolerances between seating faces shall be maintained. AU gates, thimbles, stems, and actuators shall be plumbed, shimmed, and aligned accurately. 4.6.1 Hole protection.

Tapped holes in thimbles shall be plugged for protection.

4.6.2 Surface protection.

During construction, the surfaces of the connecting

device and gate shall be covered or otherwise protected from concrete spillage, paint, oil, and debris. Any damage that occurs to the connecting device or gate in storage or handling shall be corrected prior to installation of the gate or operating and testing of the gate. 4.6.3 Thimble. Thimbles shall be positioned accurately and supported to

carefully braced both horizontally and vertically t o prevent distortion. Concrete shall be poured carefully to provide a good bond to the thimble without voids. Concrete shall be forced under the thimble up to the air-vent holes. 4.6.4 SZide.

After the entire assembly of manually actuated gates has been

installed, adjusted, and properly lubricated, each slide shall be operated for one complete cycle, open-close-open o r close-open-close. 4.6.5 Switch setting. After installation of gates with motor-actuated lift

mechanisms, torque switches shall be adjusted and limit switches set according to the manufacturer’s recommendations. The gate shall then be operated through one complete cycle, open-close-open or close-open-close. 4.6.6 Lift-mechanism storage. If hydraulic-cylinder lift mechanisms are to be

stored a t the jobsite for one month or longer, the cylinders shall be filled with oil by the purchaser at the storage site. If oil-filled cylinders are stored horizontally, they shall be rotated at least once per month. If electric lifting mechanisms are to be stored at the jobsite for one month or longer, provisions shall be made by the purchaser to energize the electrical enclosure strip heaters. 4.6.7 Cylinder. After installation of gates with hydraulic-cylinder lift mecha-

nisms, the alignment of the cylinder with the gate shall be checked by opening the gate before water is turned into the gate chamber. Binding or side thrust on the cylinder rod shall be eliminated to ensure proper cylinder operation and long life of

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prevent shifting during the pouring of the surrounding concrete. Thimbles shall be

CAST-IRON SLIDE GATES 15

seals. All connections shall be carefully checked for leaks. After proper alignment has been obtained and absence of leaks assured, the gate, submerged or subjected to normal operating heads, shall be checked through another complete cycle of operation, open-close-open or close-open-close.

4.6.8 Field leakage test.

A field leakage test may be performed by the

purchaser after installation of the slide gate. The manufacturer shall be notified of the test so as to allow sufficient time to enable a representative of the manufacturer to be present at the test site. After all adjustments have been made and the mechanisms properly lubricated, each gate slide shall be operated through one complete cycle as a final check on proper operation before starting the leakage test. Seating and unseating heads shall be measured from the top surface of the water to the center of the gate. --``,``-`-`,,`,,`,`,,`---

4.6.8.1 Seating head. Under the design seating head, the leakage shall not exceed 0.1 gpm per foot (2.07x 10-5 m3/s per metre) of seating perimeter.

4.6.8.2 Unseating head. Under the design unseating head, the leakage for heads of 20 ft (6m) or less shall not exceed 0.2 gpm per foot (4.14x

m3/s per

metre) of seating perimeter. For unseating heads greater than 20 ft (6 m), the allowable leakage shall not exceed the rate per foot (metre) of seating perimeter specified by the following equations: maximum allowable leakage (gallons per minute per foot of seating perimeter) = 0.10

+ 0.005 (unseating head in feet)

maximum allowable leakage (cubic metres per second per metre of seating perimeter) = 2.07 x

+ 3.40x io4

(unseating head in metres)

(Eq 2)

SECTION 5: VERIFICATION ~

Sec. 5.1 Inspection All work performed according to this standard shall be subject to inspection and approval by the purchaser or the purchaser’s agent. The purchaser or purchaser’s agent shall have access t o all places of manufacture where materials are being produced or fabricated or where tests are being conducted, and they shall be accorded

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16 AWWA C560-O0

full facilities for inspection and observation. Any slide gate or part that does not conform to the requirements of this standard shall be made satisfactory or shall be rejected and replaced.

Sec. 5.2 Test Procedures This standard has no applicable information for this section.

Sec. 6.1 Marking This standard has no applicable information for this section.

Sec. 6.2 Shipment Slide gates shall be complete when shipped. The manufacturer shall use all due and customary care in preparing them for shipment to avoid damage in handling or in transit. Particular care shall be taken t o make certain that the parts are completely closed and locked in position before shipment. Parts that are to be embedded in concrete may be shipped separately if requested by the purchaser. Slide gates 24 in. (600 mm) and larger shall be bolted securely or otherwise fastened to skids in such a manner that they may be safely handled.

Sec. 6.3 Affidavit of Compliance When required, the manufacturer shall provide an affidavit of compliance with all applicable provisions of this standard and with the purchaser’s specifications.

*Governmental marking, packaging, and shipping references reflect US requirements. Users of AWWA C501 in Canada, Mexico, and non-North American countries should verifi applicable local and national regulatory requirements.

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SECTION 6: DELIVERY*

APPENDIX A

Force Required to Actuate Cast-Iron Slide Gate This appendix is for information only and is not a part of AWWA C501. The maximum force required t o actuate a slide gate occurs during the unseating and raising of the weight of the slide. In the closing, or normally the downward motion of the gate, the weight of the stem and slide act in the direction of motion and reduce the force required. The force required to actuate the slide is, in part, empirically determined. The weight of the slide and stem, the head of water on the gate at the centerline of the opening, and the friction of the slide against the seats and wedges are required to calculate the force to open the gate. These factors are normally presented in the following manner:

F = 62.4 x f X Ax H

+ 1.5 x Pi + P2

([metric] F = 1000 x f x A x H

+ 1.5 x P1 + P2)

(Eq A.1)

Where: --``,``-`-`,,`,,`,`,,`---

F

= total maximum force required to open slide, lb (N)

f

= friction factor of slide against seat

A = area of gate opening, fi2 (m2) H = head of water at gate centerline, ft (m>

Pl P2

= weight of slide, lb (kg) = weight of stem, lb (kg)

The friction factor f between the slide and the seats may be taken as 0.35. The weight of the stem and slide should be obtained from the manufacturer of the gate. It has not been general practice to reduce the weight of the slide or stem because of the buoyant effect of the water. The force required to overcome the frictional effect of the wedges is accounted for by empirically assigning one half of the weight of the slide.

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18 AWWA C560-O0

Once released from the wedges, the force becomes

Fi = 62.4 x f X A x H + P i + Pz + P3 ([metric] F1 = 1000 x f x A x H

+ P1 + P 2 + P 3 )

(Eq A.2)

Where:

F1

= total maximum force required for sustained effort on the actuator, lb (kg)

p3

= 62.4 x H

x

a

x c,

lb

([metric] P3 = 1000 x H x a x c, N)

Where:

a = cross-sectional area of gate slide (gate width

x

bottom rib plan

dimension), ft2 (m2) c

= coefficient

P3 accounts for the aspiration downward force when the gate is slightly open. It is significant only on large gates and higher heads. The coefficient varies with the shape Óf the gate lip. Downward pull may be greater than the weight of the gate and under some conditions it may be negative, indicating an uplift. The c coefficient can range from less than O to more than 1.0. One manufacturer suggests a coefficient of 0.5 for bullnose shapes and 1.0 for standard bottoms.

The above forces are based on the use of a handwheel, crank, or electric-motor-actuated gate where the lift nut turns around a threaded rising stem or where the threaded stem turns inside a thrust nut on nonrising stem applications. When cylinder actuators are employed, it is suggested that the total forces calculated above should Be multiplied by a 1.3 safety factor when starting the gate from closed to open.

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Printed on recycled paper.

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