1、BRITISH STANDARD BS 2556:1973 Incorporating Amendment Nos.1,2 and3 Specification for Hand and breast drills UDC 621.951.55BS2556:1973 This British Standard, having been approved by the MechanicalEngineering IndustryStandards Committee, was published underthe authorityof the Executive Boardon 31Octob
2、er1973 BSI 01-2000 First published January1954 First revision October1973 The following BSI references relate to the work on this standard: Committee referenceMEE/120/3, MEE/120 Draft for comment71/32388 ISBN 0 580 07967 8 Co-operating organizations The Mechanical Engineering Industry Standards Comm
3、ittee, under whose supervision this British Standard was prepared, consists of representatives from the following Government departments and scientific and industrial organizations: The Government departments and scientific and industrial organizations marked with an asterisk in the above list, toge
4、ther with the following, were directly represented on the committee entrusted with the preparation of this British Standard. Associated Offices Technical Committee Engineering Equipment Users Association* Association of Consulting Engineers* Gas Council* Association of Hydraulic Equipment Institutio
5、n of Civil Engineers Manufacturers Ltd Institution of Gas Engineers Association of Mining Electrical and Institution of Heating and Ventilating Mechanical Engineers Engineers British Compressed Air Society Institution of Mechanical Engineers* British Electrical and Allied Institution of Mechanical E
6、ngineers Manufacturers Association* (Automobile Division) British Gear Manufacturers Association Institution of Plant Engineers British Internal Combustion Engine Institution of Production Engineers Manufacturers Association London Transport Executive British Mechanical Engineering Confederation Mac
7、hine Tool Trades Association British Pump Manufacturers Association Ministry of Defence British Steel Industry* Ministry of Defence, Army Department Crown Agents for Oversea Governments National Coal Board* and Administrations National Physical Laboratory Department of Employment* (Department of Tra
8、de and Industry) Department of the Environment Process Plant Association Department of Trade and Industry* Railway Industry Association of Great Britain Department of Trade and Industry Royal Institute of British Architects National Engineering Laboratory Telecommunications Engineering Electricity C
9、ouncil, the Central Electricity Manufacturing Association Generating Board and the Area Boards Water-tube Boilermakers Association in England and Wales* British Railways Board Ministry of Defence, Navy Department Engineers and Allied Hand Tool Makers National Association of Tool Dealers Association
10、Post Office Federation of British Hand Tool Manufacturers Saw Manufacturers Association Furniture Timber and Allied Trades Union Society of British Aerospace Companies Ltd Light Trades Tool Association Society of Motor Manufacturers and Traders Amendments issued since publication Amd. No. Date of is
11、sue Comments 3273 June1980 4734 June1985 7729 July1993 Indicated by a sideline in the marginBS2556:1973 BSI 01-2000 i Contents Page Co-operating organizations Inside front cover Foreword ii Section 1. General 1 Scope 1 2 Classification and terms 1 3 Thread fits 2 Section 2. Hand drills 4 Materials 8
12、 5 Hardness 8 6 Gears 8 7 Dimensions 9 8 Accuracies 9 9 Thread 9 10 Assembly 9 11 Finish 9 12 Frame strength 10 13 Performance 10 Section 3. Breast drills 14 Materials 11 15 Hardness 11 16 Gears 11 17 Dimensions 12 18 Accuracies 12 19 Thread 12 20 Assembly 12 21 Finish 13 22 Frame strength 13 23 Per
13、formance 13 Figure 1 Typical hand drill (showing open type frame) 3 Figure 2 Typical breast drill 4 Figure 3 Typical malleable iron or steel open frame for hand drills 4 Figure 4 Typical cast iron frame for hand drills 5 Figure 5 Typical semi-closed frame for hand drills 5 Figure 6 Typical cast iron
14、 frame for breast drills 6 Figure 7 Typical aluminium alloy frame for breast drills 7 Figure 8 Diagram showing direct bending moment test 10 Table 1 Materials for hand drills 8 Table 2 Materials for breast drills 11 Publications referred to 14BS2556:1973 ii BSI 01-2000 Foreword This revision of BS25
15、56 has been undertaken on the authority of the Mechanical Engineering Industry Standards Committee in order to metricate the1954 edition. At the same time special attention has been given to the component parts so as to bring the standard in line with the latest developments within the industry. NOT
16、EAttention is drawn to the certification facilities offered by BSI; see the inside back cover of this British Standard. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with
17、 a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pagesi andii, pages1to14, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendmen
18、ts incorporated. This will be indicated in the amendment table on the inside front cover.BS2556:1973 BSI 01-2000 1 Section 1. General 1 Scope This British Standard specifies the dimensions, materials, assembly and quality of hand drills and breast drills. It relates to hand drills with a capacity up
19、 to8mm and breast drills with a capacity up to12.5mm. NOTEThe titles of the British Standards referred to in this standard are listed on page 14. 2 Classifications and terms For the purposes of this British Standard the following classifications and terms apply. 2.1 Hand drill (Figure 1). A tool hav
20、ing a chuck at one end designed for rotating straight shank twist drills and similar tools. It is operated manually through simple gearing and the necessary pressure is applied through the pressure handle. 2.2 Breast drill (Figure 2). A tool intended for similar purposes as a hand drill, but of larg
21、er capacity. The tool is operated manually and has two speed ratios, while the necessary pressure is applied through a pressure pad. 2.3 Components common to both types a) Frame. The component forming the foundation and bearings for the spindle, pinions and handle. b) Open type frame. A frame which
22、allows full access to the pinions (Figure 3, Figure 4 andFigure 6). c) Semi-closed frame. A frame which is formed to act as a guard to the pinions and gear teeth, which are thus partially enclosed (Figure 5 andFigure 7). d) Gear wheel. The bevel gear for driving the tool through the pinion (EinFigur
23、e 1 and5 inFigure 2). e) Gear spindle. The spindle on which the gear wheel is mounted (FinFigure 1 and22 inFigure 2). f) Driving arm. The strip carrying the driving handle and mounted on the gear and spindle (Sin Figure 1 and20 inFigure 2). g) Driving arm screw (TinFigure 1 and21 inFigure 2). h) Dri
24、ving handle. The handle attached to the driving arm by which the spindle and chuck are rotated (PinFigure 1 and17 inFigure 2). Driving handle spindle (QinFigure 1 and18 inFigure 2). Driving handle ferrule (RinFigure 1 and11 inFigure 2). j) Steady handle. The small handle fitted to the frame on the o
25、pposite side from the driving handle, for the purposes of steadying and assisting the action of the tool when in use (GinFigure 1 and10inFigure 2). Steady handle ferrule (HinFigure 1 and11 inFigure 2). Steady handle insert (JinFigure 1 and12 inFigure 2). k) Driving pinion. The pinion which is attach
26、ed to the chuck spindle and which takes the drive from the gear wheel (LinFigure 1 and9 inFigure 2). l) Pinion pin (MinFigure 1 and24 inFigure 2). m) Chuck. The normal unguided three jaw chuck for holding the drills and similar tools (UZ inFigure 1 and2529 inFigure 2). Chuck spindle (NinFigure 1 and
27、16 inFigure 2). Chuck adaptor (UinFigure 1 and25 inFigure 2). Chuck cap (VinFigure 1 and26 inFigure 2). Chuck pad (WinFigure 1 and27 inFigure 2). Jaw spring (YinFigure 1 and28 inFigure 2). Chuck jaws (ZinFigure 1 and29 inFigure 2). 2.4 Components peculiar to hand drills a) Idle pinion. The pinion at
28、 the handle end of a hand drill which acts as a guide and extra support to the gear wheel (DinFigure 1). b) Pressure handle. The handle (AinFigure 1) at the end of the frame opposite the chuck, through which pressure is applied when the tool is in use.BS2556:1973 2 BSI 01-2000 Pressure handle insert
29、 (BinFigure 1). Pressure handle ferrule (OinFigure 1). Body pin (IinFigure 1). Thrust pad (XinFigure 1). c) Thrust ball. The hardened steel ball through which the pressure from the pressure handle and frame is conveyed to the spindle and chuck (KinFigure 1). 2.5 Components peculiar to breast drills
30、a) Pressure pad. The curved plate at the end of the stem opposite to the chuck through which pressure is applied when the tool is in use. (1inFigure 2.) Pad screw (2inFigure 2). Stem: the bar connecting the pressure pad to the frame (3inFigure 2). Stem screw (4inFigure 2). b) Gear lock assembly. The
31、 pin and other components which form the mechanism for locking the gearing in the fast or slow position (7,8 and23 inFigure 2). c) Thrust bearing. The ball, washer and cone which form the thrust assembly (13,14,15 and19 in Figure 2). 3 Threads The threads used for the chucks and spindles shall be ma
32、nufactured to the tolerances for the medium fit inBS3643, or any which are equivalent. BS2556:1973 BSI 01-2000 3 Figure 1 Typical hand drill (showing open type frame)BS2556:1973 4 BSI 01-2000 Figure 2 Typical breast drill Figure 3 Typical malleable iron or steel open frame for hand drillsBS2556:1973
33、 BSI 01-2000 5 Figure 4 Typical cast iron open frame for hand drills Figure 5 Typical semi-closed frame for hand drillsBS2556:1973 6 BSI 01-2000 Figure 6 Typical cast iron frame for breast drillsBS2556:1973 BSI 01-2000 7 Figure 7 Typical aluminium alloy frame for breast drillsBS2556:1973 8 BSI 01-20
34、00 Section 2. Hand drills 4 Materials The components shall be manufactured from the materials listed inTable 1. Table 1 Materials for hand drills 5 Hardness The chuck jaws and any other case-hardened components made from steel shall be case hardened to a depth of0.25mm and heat treated to produce a
35、hardness within the range650750HV5. 6 Gears The tool shall be the type known as the double pinion,i.e. having both a driving and idle pinion. The gear ratio shall be within the range3.6 to1 and4 to1. The gear wheel teeth shall be produced by any one of the following processes: machine cut; precision
36、 cast; precision forged. Component Materials Open frame Any suitable material which complies with the frame strength criteria specified inclause12. Semi-closed frame Cast iron to BS1452, Grade12, or to BS1490,LM2, or malleable iron toBS309 orBS 310, or steel forging to any suitable specifications in
37、BS970-1. Pressure handle insert Gear spindle Steady handle insert Chuck spindle Driving handle spindle Driving arm screw Chuck adaptor Chuck cap Body pin Pinion pin Chuck pad Thrust pad Chuck jaws Any suitable steel specification inBS970 or any other suitable material of metal, plastics or fibreglas
38、s which satisfies the performance requirements for torque given in clause13 Idle pinion Driving pinion Chuck jaws (sintered) Any suitable steel specification in BS970-1 or from sintered metal conforming toBS2590-1 or any other suitable material of metal, plastics or fibreglass which satisfies the pe
39、rformance requirements for torque given in clause13 Gear wheel BS1452 Grade12, or any suitable steel specification inBS970 or any suitable sintered metal inBS2590 or any other suitable material of metal, plastics or fibreglass which satisfies the performance requirements for torque given in clause13
40、 Steady handle ferrule Pressure handle ferrule Driving handle ferrule Driving arm BS1449-1. Pressure handle Steady handle Driving handle Suitable hardwood or any other material which may be agreed between the purchaser and the manufacturer. The timber shall be straight grained and free from defects.
41、 Moisture content shall be not less than10% and not more than15%.BS2556:1973 BSI 01-2000 9 7 Dimensions The dimensions of the hand drill and its components shall be those given below. 8 Accuracies 8.1 Bearings. The accuracy of fit between the chuck spindle and front bearing shall be such that the ma
42、ximum possible clearance is0.06mm. 8.2 Assembly. The dimensional accuracy of all the components shall be such that the complete assembly functions efficiently and the total variation in reading of a dial indicator applied25mm in front of the chuck nose, on a test bar4.75mm diameter which is rotated
43、with the tool, shall not exceed0.5mm. 9 Thread The major diameter of the screw thread on the chuck and spindle when manufactured in accordance with BS3643 shall be not less than10mm. 10 Assembly Hand drills shall be fitted with a single ball thrust pad between the frame and the chuck spindle above t
44、he pinion, as indicated atK andX inFigure 1. Adequate provision shall be provided for the lubrication of the driving pinion bearing and the idle pinion. The driving handle spindle shall be shouldered and riveted securely and positively in position through the driving arm in order to withstand normal
45、 manual usage. The steady handle shall be attached to the frame by a screwed stud insert and shall be readily removable. The chucks shall be self-centering with three unguided jaws. Key type chucks may be fitted by agreement between the purchaser and the manufacturer. The pressure handle may be atta
46、ched to the body by means of an integral tang providing the drill complies with clauses8 and12. 11 Finish 11.1 General components. All the component parts of the hand drills shall be smoothly and neatly finished with all burrs and sharp corners removed. 11.2 Frame and gear wheel. The frame and gear
47、wheel (except for parts which are plated) shall be stove enamelled, epoxy powder coated or have a finish of equivalent quality and durability. 11.3 Gear wheel rim, chuck shell, driving arm. These components shall be nickel or chromium plated in accordance with the provisions of BS1224. Alternative f
48、inishes to the above, including being left bright, may be used by arrangement between the manufacturer and the purchaser. Maximum overall length with chuckclosed 335mm Pressure handle Minimum overall length110mm Minimum size of largest diameter30mm Driving arm Minimum length85mm Minimum width14mm Mi
49、nimum thickness2.5mm Front bearing Minimum length30mm Chuck spindle No part which is subject to torque shall be less in diameter than7.5mm Steady handle Minimum size of largest diameter30mm Minimum overall length50mm Driving handle Minimum size of largest diameter22mm Minimum overall length35.5mm Driving handle spindle Minimum diameter5.5mm stepped to4.75mm at riveting endBS2556:1973 10 BSI 01-2000 12 Frame strength To ensure adequate strength of open framed hand-drills, the finished fully machined frame shall be capable
