1 Scope
This document specifies the requirements and methods for eliminating hazards or reducing risks in the design of the following categories of metal cutting lathes and turning centres.
Category 1:Manually controlled lathes without numerical control.
Category 2:Manually controlled lathes with limited numerical control.
Category 3: CNC lathes and turning centres.
Class 4: Single or multi-axis automatic lathes.
Note 1: See 3.4 for more detailed information on machine classification and 3.3 for mandatory and optional configurations of operating modes.
Note 2: The requirements of this document are generally applicable to all types of lathes. If some requirements apply only to a certain type of lathe, the type of lathe has been specified.
Note 3: Hazards arising from other metal cutting processes (e.g. grinding and laser machining) are described in other standards (see references).
The important hazards listed in chapter 4 of this document also apply to auxiliary equipment integrated into the machine tool (e.g. workpieces, tools and workholding devices, handling equipment and chip removal devices).
This document also applies to machines or turning units integrated into automatic production lines, where the hazards and risks are similar to those of a stand-alone machine.
This document includes essential information on safety to be provided by the manufacturer to the user. See Figure 2 in GB/T15706 - 2012 for a diagrammatic illustration of the responsibilities between the manufacturer and the user with regard to operational safety.
The user's responsibility is to identify certain hazards (e.g. fires and explosions) and to minimise the critical risk factors associated with them (e.g. centralised control of whether the exhaust unit is working properly).
Where other processes (milling, grinding, etc.) are involved, this document refers only to the basic content of the safety requirements; for further details, see the references.
This document applies to machines produced after the date of publication.
2 Normative references
The contents of the following documents constitute essential provisions of this document by means of normative references in the text. Among them, note the date of reference documents, only the date of the corresponding version applicable to this document; do not note the date of reference documents, its latest version (including all the revision of the list) applicable to this document.
GB/T 3766-2015 General rules and safety requirements for hydraulic drive systems and their components (ISO 4413:2010, MOD)
GB/T 3767-2016 Engineering method for the determination of sound power levels and sound energy levels of noise sources by acoustic sound pressure method for the approximate free field above the reflecting surface (ISO 3744:2010,IDT)
GB/T3768-2017 Acoustic sound pressure method for the determination of sound power levels and sound energy levels of noise sources using the simple method of enveloping the measurement surface above the reflecting surface (ISO 3746:2010,IDT)
3 Terms and definitions
The terms defined in GB/T 15706-2012,GB/T 16855.1-2018 and the following terms and definitions apply to this document.
3.1 General terms
3.1.1
Turning machine
A machine tool in which the workpiece is rotated with respect to a stationary tool as the main motion for cutting.
3.1.2
manual control
Each movement of the machine is started and controlled individually by the operator.
4 List of main hazards
4.1 General requirements
The manufacturer of the lathe should carry out a risk assessment of the machine according to the requirements of GB/T 15706-2012. The list of hazards and hazardous conditions in Table 3 is the result of the risk assessment of the lathes within the scope of this document according to Chapter 5 of GB/T 15706-2012, followed by the identification of hazards according to 5.4 of GB/T 15706-2012. The risk assessment assumes that risks are derived from all sources.
The risk assessment assumes that risks arise from all sources, including accidental start-ups. Risks arising not only from operators and others who may enter the danger zone are identified, but also from the various conditions that may arise during the machine's life cycle (e.g. commissioning, production, maintenance, repair and re-commissioning after maintenance). The analysis of the impact of control system failures is also included in the scope of the assessment.
In addition, users of this document (e.g. designers, manufacturers and suppliers) should pay particular attention to the following aspects when carrying out risk assessments of machine tools:
a) The intended use of the machine tool, including maintenance, adjustment and cleaning as well as reasonably foreseeable misuse (see 3.23 and 3.24 in GB/T 15706-2012);
b) identification of significant hazards associated with the machine tool.
5 Safety requirements and protective measures
5.1 General requirements
5.1.1 General rules
Lathes and turning centres shall comply with the safety requirements and/or measures in this chapter. Without going into deeper risks in this document, machine tools shall be designed in accordance with the basic principles in Chapter 5 of GB/T 15706-2012.
The requirements on how to reduce risks in design are described in chapter 6 of GB/T 15706-2012, and safety measures are described in 6.3 of GB/T 15706-2012.
5.2 Specific requirements for Chapter 4 mechanical risk factors 5.2.11 Class machine tools
The main protective measures for machine tools of category 1 (manual lathes without CNC functions) are as follows:
a) A movable chuck guard shall be provided to prevent or limit access to the rotating workpiece clamping device and to minimise the damage caused by the chuck jaws being thrown out. The design and construction requirements are described in 5.13. The guard shall be interlocked with the spindle operation [see 5.11 b) 1) The width of the guard shall cover the entire width of the chuck body. The guard should reach the outermost point of the normal chuck jaw extension. Excluding
The workpiece protrusion from the chuck is not included.
2) The minimum circumferential length should cover the centre line of the rotating workpiece clamping device.
6 Information on use
Note:See 6.4 in GB/T 15706-2012.
6.1 Marking
The lathe should be provided with a marking that complies with 6.4.4 in GB/T 15706-2012.
It shall contain at least the following elements:
a) clearly marked with:
The name of the machine, the manufacturer's full address and, if required, the legal representative;
"Lathe", series number or machine type, type of machine to which it belongs, size;
The factory number, if available
The date of manufacture, the year in which the machine was built.
b) Indicate the compulsory requirements to which it is subject [e.g. mandatory European Union safety (CE) certification].
c) For safe use:
Maximum speed limit of the spindle, r/min;
Maximum speed limit of the chuck, r/min, except when using an integral bar clamping chuck or a power chuck in accordance with GB/T 23290-2009
Horizontal lathes or machines used for bar processing, where it is likely that the bar stock or bar support will extend beyond the back end of the spindle or the bar feeder, should be protected by a warning message informing of the risk of shaking and throwing out;
Guards, protective devices and other components of the machine that are not permanently attached to the machine shall provide identifiable data and information in a conspicuous position;
If there is a risk of fire and/or explosion, the machine shall be suitably marked to indicate how to extinguish the fire.
6.2 Operating instructions
6.2.1 General requirements
The operating instructions shall comply with the provisions of 6.4.5 of GB/T 15706-2012 and contain all specific information about the lathe, which shall be provided to the user together with the machine.
The instruction manual shall include all information on transport, assembly/disassembly, operation, adjustment, maintenance, cleaning, etc., for the purpose of training or making the operator proficient and safe in the use of the machine at a later stage.
Appendix A (normative) Impact test methods for lathe guards
Appendix B (informative) Examples of impact test equipment and materials
Appendix c (informative) Calculation of direct impact energy
Appendix D (informative) Example of a safety function checklist
Appendix E (informative) Examples of exhaust (smoke) and fire suppression systems
Appendix F (informative) Example of interlocking guards performance level determination
Foreword
1 Scope
2 Normative references
3 Terms and definitions
4 List of main hazards
5 Safety requirements and protective measures
6 Information on use
Appendix A (normative) Impact test methods for lathe guards
Appendix B (informative) Examples of impact test equipment and materials
Appendix c (informative) Calculation of direct impact energy
Appendix D (informative) Example of a safety function checklist
Appendix E (informative) Examples of exhaust (smoke) and fire suppression systems
Appendix F (informative) Example of interlocking guards performance level determination
