Oil Field Chain and Sprockets

API SPECIFICATION 7F

EIGHTH EDITION, NOVEMBER 2010 EFFECTIVE DATE: MAY 1, 2011

ERRATA, MAY 2013

REAFFIRMED, APRIL 2016

Special Notes

API publications necessarily address problems of a general nature. With respect to particular circumstances, local, state, and federal laws and regulations should be reviewed.

Neither API nor any of API's employees, subcontractors, consultants, committees, or other assignees make any warranty or representation, either express or implied, with respect to the accuracy, completeness, or usefulness of the information contained herein, or assume any liability or responsibility for any use, or the results of such use, of any information or process disclosed in this publication. Neither API nor any of API's employees, subcontractors, consultants, or other assignees represent that use of this publication would not infringe upon privately owned rights.

API publications may be used by anyone desiring to do so. Every effort has been made by the Institute to assure the accuracy and reliability of the data contained in them; however, the Institute makes no representation, warranty, or guarantee in connection with this publication and hereby expressly disclaims any liability or responsibility for loss or damage resulting from its use or for the violation of any authorities having jurisdiction with which this publication may conflict.

API publications are published to facilitate the broad availability of proven, sound engineering and operating practices. These publications are not intended to obviate the need for applying sound engineering judgment regarding when and where these publications should be utilized. The formulation and publication of API publications is not intended in any way to inhibit anyone from using any other practices.

Any manufacturer marking equipment or materials in conformance with the marking requirements of an API standard is solely responsible for complying with all the applicable requirements of that standard. API does not represent, warrant, or guarantee that such products do in fact conform to the applicable API standard.

Users of this Specification should not rely exclusively on the information contained in this document. Sound business, scientific, engineering, and safety judgment should be used in employing the information contained herein.

All rights reserved. No part of this work may be reproduced, translated, stored in a retrieval system, or transmitted by any means, electronic, mechanical, photocopying, recording, or otherwise, without prior written permission from the publisher. Contact the Publisher, API Publishing Services, 1220 L Street, NW, Washington, DC 20005.

Copyright © 2010 American Petroleum Institute

Foreword

Nothing contained in any API publication is to be construed as granting any right, by implication or otherwise, for the manufacture, sale, or use of any method, apparatus, or product covered by letters patent. Neither should anything contained in the publication be construed as insuring anyone against liability for infringement of letters patent.

Shall: As used in a standard, “shall: denotes a minimum requirement in order to conform to the specification.

Should: As used in a standard, “should” denotes a recommendation or that which is advised but not required in order to conform to the specification.

This document was produced under API standardization procedures that ensure appropriate notification and participation in the developmental process and is designated as an API standard. Questions concerning the interpretation of the content of this publication or comments and questions concerning the procedures under which this publication was developed should be directed in writing to the Director of Standards, American Petroleum Institute, 1220 L Street, NW, Washington, DC 20005. Requests for permission to reproduce or translate all or any part of the material published herein should also be addressed to the director.

Generally, API standards are reviewed and revised, reaffirmed, or withdrawn at least every five years. A one-time extension of up to two years may be added to this review cycle. Status of the publication can be ascertained from the API Standards Department, telephone (202) 682-8000. A catalog of API publications and materials is published annually by API, 1220 L Street, NW, Washington, DC 20005.

Suggested revisions are invited and should be submitted to the Standards Department, API, 1220 L Street, NW, Washington, DC 20005, standards@api.org.

iii

Introduction vi

1. Scope 1

2. Normative References 1

3. Roller Chain 1

   1. Chain Designation 1

   2. Heavy Series Chains 1

   3. Dimensions 2

   4. Chain Length Tolerance 2

   5. Tensile Strength 2

   6. Preloading 3

   7. Minimum Press-out Force 3

   8. Minimum Dynamic Strength 5

   9. Marking Requirements 5

Annex A (informative) Recommended Practice for Installation, Lubrication, and Maintenance

of Roller Chain Drives 6

Annex B (informative) Sprockets for Roller Chain 25

Annex C (informative) Use of the API Monogram by Licensees 27

Bibliography 30

Figures

1. Chain Assembly 2

2. Single and Multiple Chain Assemblies 2

1. Align Shafts 7

2. Align Sprockets 7

3. Mid-span Movement Diagram 8

4. Lubricant Flow into the Chain Joint 9

5. Application of Lubricant to Chain 10

6. Drip Feed Lubrication 12

7. Oil Bath Lubrication 12

8. Slinger Disc Lubrication 13

9. Oil Stream Lubrication 14

10. Typical Oil Retaining Chain Casing 15

11. Casing Clearance Wear Limit 15

12. Chain Casing Schematic 16

13. Approximation of Temperature Rise of a Chain Casing 16

14. Measurement of Chain for Wear Elongation 22

15. Worn Sprocket 23

1. Sprocket Types 25

2. Sprocket Tooth Profile 26

v

Tables

1. Chain Length Tolerance 3

2. Table of Standard Chain Capacities 4

1. Recommended Oil Viscosities for Various Temperatures 10

2. Lubrication Type for Chain Size and Speed 11

3. Required Oil Flow for Chain Drives 14

4. Roler Chain Drive Troubleshooting Guide 19

5. Chain Wear Elongation Limits 23

Introduction

This specification is under the jurisdiction of the API Subcommittee on Drilling Structures and Equipment.

The purpose of this specification is to provide standards for roller chains suitable for use in oil field drilling and producing operations.

Much of the engineering material pertaining to roller chains and sprockets was base on ASME B29.1 and the book Chains for Power Transmission and Material Handling, published by the American Chain Association. Additionally, portions of ASME B29.1 are requirements of this specification as referenced herein.

Some of the performance related characteristics of the chains that are contained in this document are specific to oil field chains and to their application to oil field drives. This information cannot be found in other publications and imposes performance testing that goes beyond the basic requirements found in any other standards or specifications.

A section on drive design has not been included in this edition of the specification due to the great variety of applications and the complexity of the subject drives.

Conversions of U.S. Customary Units (USC) to International System (SI) metric units are provided for reference only throughout the text of this specification in parentheses, e.g., 6 in. (152.4 mm). SI equivalents have also been included in all tables. Formulas and certain relationships are intentionally presented only in U.S. Customary Units to preclude any ambiguity between them and tabulated values. Conversion factors are provided below if SI equivalents are desired for the calculated unit values.

U.S. Customary Units are in all cases preferential and shall be standard in this specification. Products are to be marked in the units in which ordered unless there is an agreement to the contrary between the Purchaser and the Manufacturer.

The following formula was used to convert degrees Fahrenheit (F) to degrees Celsius (C):

°C = 5/9 (°F – 32)

vi

Oil Field Chain and Sprockets

1. Scope

   
   

   This specification covers the manufacture of the components for, and the assembly and packaging of, single and multiple strand, number 40 through 240, standard and heavy series roller chains for oil field applications, including chain designation, chain length tolerance, tensile strength specifications, pin and bushing press-out specifications, and dynamic test requirements.

   
   

   For informational purposes, Annex A provides recommendations for installation, lubrication, and maintenance of oil field chain drives and Annex B includes a basic description of roller chain sprockets.

   
   

2. Normative References

   
   

   The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.

   
   

   ASME1 B29.1, Precision Power Transmission Roller Chains, Attachments and Sprockets

   
   

   ASME B29.26, Fatigue Testing Power Transmission Roller Chain

   
   

3. Roller Chain

   
   

   1. Chain Designation

      
      

      Chain covered by this specification is identified by the designation shown in the following example and in more detail in ASME B29.1.

      
      

      
      

      1 6 0 H — 6

      
      

      Chain number

      
      

      Number of strands (not stamped on plates)

      
      

      Heavy series (omit on standard chain)

      
      

      Conventional chain with rollers (other digits indicate unique characteristics)

      
      

      
      

   2. Heavy Series Chains

Heavy series chains are made in ¾ in. (19.05 mm) and larger pitches and differ from standard series chains in thicknesses of link plates. Their value is only in the acceptance of higher loads during low-speed operation.

1 ASME International, 3 Park Avenue, New York, NY, 10016-5990, www.asme.org.

1