Better Tools for the Job: Specifications for Hand Tools and Equipment - Softcover

Armstrong, William

 
9780903031714: Better Tools for the Job: Specifications for Hand Tools and Equipment

Inhaltsangabe

These simple specifications, although originally applied to the Kenya road program, are equally applicable to labour-intensive projects in other countries.

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Better Tools for the Job

Specifications for Hand Tools and Equipment

By William Armstrong

Practical Action Publishing Ltd

Copyright © 1980 Intermediate Technology Publications
All rights reserved.
ISBN: 978-0-903031-71-4

Contents

Acknowledgements, 4,
1. Introduction, 5,
2. Specifications, 6,
3. Tool Handles, 7,
4. Wheelbarrows, 8,
5. Tractors and Trailers, 9,
6. Procurement, Stores, and inspection, 11,
7. Maintenance in the field, 12,
Detailed Specifications:,
105 Shovel, 14,
106 Plain Jembe (Hoe), 16,
107 Wheelbarrow (TU Model), 18,
108 Fork Jembe, 22,
109 Crowbar, 24,
110 Trailer (5 tonne tipping), 25,
111 Panga, 28,
112 Mattock, 30,
113 Shovel Handle, 33,
114A Jembe/Fork Jembe Handle, 34,
114B Pick/Mattock Handle, 35,
114C Axe Handle, 36,
114E Sledgehammer Handle, 37,
115 Axe, 38,
116 Pickaxe, 40,
117 Spreader (Rake), 42,
118 Rammer, 43,


CHAPTER 1

Introduction


The simple specifications for hand tools and equipment contained in this publication and the various notes relating to them were developed in connection with the Kenya Rural Access Roads Programme. This programme is a Government of Kenya (Ministry of Works) project supported by the World Bank, the British Government, USAID, and certain other Governments. Started in 1975, the plan was to build some 15,000 kilometres of simple unsealed roads in remote parts of the country using labour intensive methods during an approximate 10 year period. It is anticipated that over 10,000 people will be employed at the peak. Besides helping to reduce unemployment the programme has socio/economic merits in opening up remote areas, thus stimulating agricultural production and aiding education and medical care.

It will be appreciated that such a project calls for the use of very large quantities of hand tools such as shovels, jembes, etc., and simple equipment such as wheelbarrows. At the outset of the RARP the quality of these items was, in general, very poor leading to breakages, supply difficulties, and low productivity in the field. The basic reason for this very unsatisfactory situation was the practice of buying tools and equipment by tender at the lowest quoted price, resulting in the provision of tools of poor design which lacked strength and durability.

Regrettably this same policy of buying at lowest tender price is common in many developing countries, and results in similar unsatisfactory performances when the tools and equipment are put to work in the field.

Attached to the Kenya MOW in Nairobi was a Technology Unit which among other functions worked intensively on the upgrading of tool and equipment quality. By the end of 1978 this work had drawn to a successful conclusion and the simple specifications and other data in this book record the information developed, so that it is now available for labour intensive projects of many types in other countries.

It may be added that insofar as the Kenya RARP is concerned, work done on tool and equipment improvement and the use of these specifications when buying has been a major factor in eliminating shortages, reducing wear and breakages in the field, and increasing productivity. Thus the work has been cost effective and hand tools and equipment are no longer a delaying factor in the programme.

CHAPTER 2

Specifications


The full list of simple specifications 1 05-118 is given in the contents section at the beginning of the book.

It should be emphasised that these simple specifications are not intended to replace the more detailed national or international specifications such as BSS, SAE, etc, nor do they cut across the work performed by any Bureau of Standards. Rather, they represent practical and manageable information (together with simple drawings) which can be used commercially for buying, inspection, and testing, thus ensuring that the various items procured will be durable and give good productivity in service.

In order to obtain good quality durable hand tools the use of steel to reasonably controlled specifications is essential. The strength and behaviour of steel depends on its chemical composition (and heat treatment where relevant), and for this reason the required chemical composition of the steel forms part of each hand tool specification.

In the absence of a local steel industry much of the steel will have to be imported, a situation which applies particularly to the special alloy steel needed, for example, for axe manufacture (Specification 115).

At first sight the inclusion of chemical compositions in the specifications might appear to involve complications in the form of analysis for inspection purposes. Fortunately, however, there is a good correlation between the strength of steel and its hardness, and it is for this reason that hardness figures are included in each hand tool specification. The equipment needed for hardness checking (covering only 0.2% of items received – see section 6) is fairly simple and inexpensive and may be located in the store's facilities. Briefly, the checking process consists of pressing a diamond or hardened ball into the steel with a definite load. The diameter of the indentation gives the required correlation with the strength of the steel, based on standard tables.

Thus the need for chemical analysis can be reduced to occasional random checks, probably carried out at the local university, or similar institution.

It will be noted that each specification calls for the tool to be marked clearly with the specification number and the manufacturer's name and/or trademark. These points are important for keeping track of tools in the field and discouraging the introduction of low grade non-specified items.

CHAPTER 3

Tool Handles


Experience in several developing countries has indicated that a very large proportion of the problems encountered with hand tools in the field (on road, irrigation, and construction projects, for example) arise from the use of handles made from cheap unseasoned softwood, coupled with poor manufacturing quality. Breakages, loose tool heads, and unsatisfactory grips are typical problems, leading to poor productivity and waste of time.

This is surprising since suitable hardwoods are widely available, seasoning can be carried out naturally if kilns are not in use, and there appears generally to be adequate manufacturing capability either by machine, or, in rural areas, by manual methods.

Thus the manufacture of tool handles to specification is a vital and relatively easy step in the upgrading of hand tool quality and productivity in the field. The cost increase for a "specified" handle as compared with a "cheap" handle is modest, and no other single step can return such high dividends in terms of cost effectiveness and productivity as the manufacture of tool handles to specification from seasoned hardwood.

It is for this reason that specifications 113, 114A, 114B, 114C, 114E, covering handles for various types of tools are included in this publication.

Suitable hardwoods will have specific gravity 0.66-0.80 after seasoning and will preferably be long grained. Seasoning should be to a moisture content of 20% maximum, either by kiln or natural means. Natural seasoning may take about seven weeks. In view of the very large variety of hardwoods in different parts of the world it is recommended that the selection of appropriate types for tool...

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