Skip to product information
1 of 12

PayPal, credit cards. Download editable-PDF and invoice in 1 second!

GB/T 3766-2015 English PDF (GBT3766-2015)

GB/T 3766-2015 English PDF (GBT3766-2015)

Regular price $175.00 USD
Regular price Sale price $175.00 USD
Sale Sold out
Shipping calculated at checkout.
Quotation: In 1-minute, 24-hr self-service. Click here GB/T 3766-2015 to get it for Purchase Approval, Bank TT...

GB/T 3766-2015: Hydraulic fluid power -- General rules and safety requirements for systems and their components

This Standard specifies general rules and safety requirements for hydraulic systems and their components used on machinery as defined by 3.1 in GB/T 15706-2012. This Standard deals with all significant hazards associated with hydraulic systems and specifies the principles to avoid those hazards when the systems are put to their intended use.
GB/T 3766-2015
ICS 23.100.01
J 20
Replacing GB/T 3766-2001
Hydraulic fluid power - General rules and safety
requirements for systems and their components
Issued by. General Administration of Quality Supervision, Inspection and Quarantine of the PRC;
Standardization Administration of the PRC.
Table of Contents
Foreword ... 3
Introduction ... 7
1 Scope ... 8
2 Normative references ... 8
3 Terms and definitions ... 10
4 List of significant hazards ... 10
5 General rules and safety requirements ... 11
5.1 General ... 11
5.2 Basic requirements for the design and technical specification of hydraulic systems ... 11
5.3 Additional requirements ... 13
5.4 Specific requirements for components and controls ... 16
6 Verification of safety requirements and acceptance testing ... 41
7 Information for use ... 42
7.1 General requirements ... 42
7.2 Final information for hydraulic systems on stationary industrial machinery ... 42 7.3 Maintenance and operating data ... 42
7.4 Marking and identification ... 45
8 Identification statement ... 47
Appendix A (Informative) List of significant hazards ... 48
Appendix B (Informative) Form for collecting hydraulic system and component data ... 51
Bibliography ... 60
Hydraulic fluid power - General rules and safety
requirements for systems and their components
1 Scope
This Standard specifies general rules and safety requirements for hydraulic systems and their components used on machinery as defined by 3.1 in GB/T 15706-2012. This Standard deals with all significant hazards associated with hydraulic systems and specifies the principles to avoid those hazards when the systems are put to their intended use.
Note 1. SEE Clause 4 and Appendix A for information related to significant hazards. The significant hazard noise is incompletely dealt with in this Standard. Note 2. Noise emission depends especially on the installation of hydraulic components or systems into machinery.
This Standard applies to the design, construction, installation, and maintenance of hydraulic systems and their components, also taking into account the following aspects.
a) Assembly;
b) Installation;
c) Adjustment;
d) Operation;
e) Maintenance and cleaning;
f) Reliability;
g) Energy efficiency;
h) Environment.
2 Normative references
The following documents are indispensable for the application of this document. For the dated references, only the versions with the dates indicated are applicable to this document. For the undated references, the latest version (including all the amendments) are applicable to this document.
GB/T 786.1 Fluid power systems and components - Graphic symbols and
circuit diagrams - Part 1. Graphic symbols for conventional use and data- processing applications (GB/T 786.1-2009, ISO 1219-1.2006, IDT)
GB/T 2878.1 Connections for hydraulic fluid power - Ports and stud ends with metric threads and O-ring sealing - Part 1. Ports (GB/T 2878.1-2011, ISO 6149-1.2006, IDT)
GB/T 2878.2 Connections for hydraulic fluid power - Ports and stud ends with metric threads and O-ring sealing - Part 2. Heavy-duty stud ends (S series) (GB/T 2878.2-2011, ISO 6149-2.2006, MOD)
GB/T 14039 Hydraulic fluid power - Fluids - Method for coding the level of contamination by solid particles (GB/T 14039-2002, ISO 4406.1999, MOD)
GB/T 14048.14 Low-voltage switchgear and controlgear - Part 5-5. Control circuit devices and switching elements - Electrical emergency stop device with mechanical latching function (GB/T 14048.14-2006, IEC 60947-5-
5.1997, IDT)
GB/T 15706-2012 Safety of machinery - General principles for design - Risk assessment and risk reduction (ISO 12100.2010, IDT)
GB 16754 Safety of machinery - Emergency stop - Principles for design (GB 16754-2008, ISO 13850.2006, IDT)
GB/T 17446 Fluid power systems and components - Vocabulary (GB/T
17446-2012, ISO 5598.2008, IDT)
GB/T 17489 Hydraulic fluid power - Particulate contamination analysis - Extraction of fluid samples from lines of an operation system (GB/T 17489- 1998, idt ISO 4021.1992)
GB/T 19671 Safety of machinery - Two-hand control device - Functional
aspects and design principles (GB/T 19671-2005, ISO 13851.2002, MOD)
GB/T 25133 Hydraulic fluid power systems - Methods of cleaning lines by flushing (GB/T 25133-2010, ISO 23309.2007, IDT)
ISO 1219-2 Fluid power systems and components - Graphic symbols and
circuit diagrams - Part 2. Circuit diagrams
5.2.2 Unintended pressures All related parts of the system shall be designed or otherwise protected against foreseeable pressures exceeding the maximum working pressure of a system or the rated pressure of any part of the system if the excessive pressure can cause a hazard.
Any system or part of a system may be disconnected and sealed, so that
trapped fluid can be subject to a pressure increase or decrease (e.g. due to the change in a load or the fluid temperature). If the change can cause a hazard, the system or the part of the system shall include means for limiting the pressure. The preferred means of protection against excessive pressure is to set one or more safety overflow valves (pressure-relief valves), to limit the pressure in all related parts of the system. Other means, such as pressure-compensator pump controls, may be used to limit main system operating pressure, provided these means can ensure safety under all operating conditions. Systems shall be designed, constructed, and adjusted to limit pressure surges and fluctuations. Pressure surges and fluctuations shall not cause hazards. Loss of pressure or pressure drop shall not expose persons to a hazard and shall not damage the machinery. Means shall be provided to prevent unacceptable pressure build-up where high external loads are reflected on actuators.
5.2.3 Mechanical movements
In stationary industrial machinery, mechanical movements, whether intended or unintended (e.g. effects from acceleration, deceleration or lifting/holding of masses), shall not result in a situation hazardous to persons.
5.2.4 Noise
In the design of hydraulic systems, the expected noise shall be taken into account, and noise generation shall be minimized at its source. Depending on the actual application, measures shall be taken to minimize the risks caused by noise. Airborne, structure-borne, and liquid-borne noise shall be considered. Note. For the design of low-noise machinery and systems, SEE GB/T 25078.1. 5.2.5 Leakage
If leakage (internal or external) occurs, it shall not cause a hazard.
a) minimizes the loss of hydraulic fluid;
b) for stationary machinery only, does not require the draining of the reservoir; c) does not necessitate an otherwise needless disassembly of adjacent parts. 5.3.3 Cleaning and painting During external cleaning and painting of machinery, sensitive materials shall be protected from incompatible liquids. During painting, areas that shall not be painted (e.g. piston rods, indicator lights) shall be covered and the coverings removed afterwards. After painting, all warnings and safety-related markings shall be visible and legible. 5.3.4 Preparation for transportation Identification of piping
Whenever it is necessary to dismantle hydraulic systems for transportation and where an incorrect reconnection can cause a hazard, the piping and
corresponding connections shall be clearly identified. The identification shall correspond to the data on all appropriate documentation. Packaging
All parts of the hydraulic system shall be packaged for transportation in a manner that can preserve their identification and protect them from damage, distortion, contamination and corrosion. Sealing and protection of openings
Exposed openings in hydraulic systems and components, in particular tubes and hoses, shall be protected during transportation either by being sealed or stored in an appropriately clean and closed container. Male threads shall be protected. Any protective device used shall be removed when reassembled. Handling facilities
Transport sizes and masses shall be consistent with the handling facilities available provided by the purchaser (e.g. lifting tackle, passageways, ground loading); SEE B.1.5. If necessary, the hydraulic system shall be designed such that it can be easily disassembled into subassemblies.
5.4 Specific requirements for components and controls
5.4.1 Hydraulic pumps and motors Adjustable stroke end stops
Means shall be provided to prevent loosening of adjustable external or internal stroke end stops. Piston stroke
The stroke lengths, including tolerances, if not specified in the relevant standard, shall be specified, depending on the application of the hydraulic system. Note. SEE JB/T 10205 for the tolerances of stroke lengths. Piston rods Material, finish and protection
Proper piston-rod material and finish shall be selected to minimize wear, corrosion and foreseeable impact damage.
Piston rods shall be protected against foreseeable damage from dents,
scratches, corrosion, etc.. Protective covers may also be used. Assembly
For assembly purposes, piston rods with threaded ends shall be provided with structures to apply counter forces by a wrench; SEE ISO 4395. Pistons shall be positively locked to piston rods. Maintenance of sealing devices and wear parts
Sealing devices and other wear parts that are intended to be serviced shall be easily replaceable. Air bleeding Location of air bleeds
Cylinders on stationary industrial machinery shall be mounted so that they are self-bleeding, or accessible external air bleeds shall be provided. Cylinders shall be installed with air bleeds uppermost. Where these requirements are not feasible, maintenance and service information shall be provided; SEE g), n), and r). Air vent ports
Cylinders with air-filled chambers shall have their air-vent ports designed or positioned to avoid hazards. The hydraulic cylinder shall be able to vent air without hazards by using the air-vent ports. Identification
Manifold assemblies and their components shall be labelled for reference in accordance with ISO 16874. When this is not possible, the identification shall be provided by other means. Electrically operated valves Electrical connections and solenoids Electrical connections
Electrical connections shall be in accordance with appropriate standards (e.g. GB 5226.1 or manufacturer standard) and be designed with the suitable
protection class (e.g. in accordance with GB 4208). Solenoids
Appropriate solenoids shall be selected (e.g. cyclic rate, temperature rating, voltage tolerance) so that they are capable of operating the valves at the specified conditions. Manual or other overrides
If it is necessary to operate an electrically operated valve when electrical power is not available, it shall be provided with means for an override. Overrides shall be designed or selected so that the risk of inadvertent operation is minimized; and they shall reset when the override control is removed, unless otherwise specified. Adjustments
When valves permit adjustments of one or more parameters, the following provisions may be incorporated, as appropriate.
a) Means for securing the adjustment;
b) Means for locking the adjustment, if required to prevent unauthorized change;
c) Means for preventing adjustment beyond a safe range.
5.4.5 Hydraulic fluids and conditioning components Hydraulic fluids Specification
b) shall maintain the fluid level at a safe working height and allow sufficient fluid access to supply lines during all operating cycles and operating
c) shall allow adequate space for thermal expansion and air separation of hydraulic fluid.
d) for hydraulic systems in stationary industrial machinery, shall be installed either over a pan, or equivalent device, of suitable capacity and
configuration in order to effectively collect major accidental spillage from the reservoirs [SEE also 5.2.5 and 5.3.1n)], or over all impermeable areas. Note. Design requirements in these cases can be subject to national legal provisions. e) shall be able to provide passive cooling to control the system fluid temperature; when passive cooling is not sufficient, active cooling shall be provided; SEE
f) shall provide a slow recirculating velocity of reservoir hydraulic fluid that allows for the release of entrained air and the precipitation of heavy
g) shall separate the return fluid from pump inlet lines by baffles or other means; if baffles are used, they shall not prevent thorough cleaning of the reservoirs, and shall not cause a fluid level difference between the suction zone and the return zone when the hydraulic system is operating normally. h) for hydraulic systems in stationary industrial machinery, shall be provided with bottom-supporting legs or members to raise the reservoir a minimum of 150 mm above the floor to facilitate handling, draining and heat
dissipation. Sufficient area for four legs or supporting members of
reservoirs shall be provided for foundation anchoring and levelling.
If the fluid reservoir is of the pressure-sealed type, the special requirements of that type shall be considered. Construction Spillage
Provisions shall be made to prevent spilled fluid from returning directly to the reservoir. Vibration and noise
Care shall be taken to prevent excessive structure-borne vibration and airborne noise, particularly when components are mounted in or directly to the reservoir. replaced by one person. The alternative inspection means, e.g. an
endoscope, are allowed.
b) Suction strainers, return diffusers and other replaceable internal reservoir components shall be easily accessible for removal or cleaning.
c) Reservoirs shall have means that they can be easily emptied in the
assembled position.
d) Reservoirs on stationary industrial machinery shall be shaped to allow complete draining of hydraulic fluid in the assembled position. Structural integrity
Reservoirs shall be designed to provide adequate structural integrity when they a) are filled to maximum capacity with the system fluid;
b) are subjected to positive and negative pressures caused by the withdrawal or return of fluid at rates required by the system under all foreseeable conditions;
c) support mounted components;
d) undergo transport.
If lifting points are provided on the reservoir for transporting, the supporting structure and attaching provisions shall be sufficiently robust to withstand the maximum expected handling force, including foreseeable impact and jerk, with no detrimental effect. The means of attachment shall be sufficiently strong and elastic to maintain secure restraint of the system parts mounted on, or attached to, the reservoir during handling and transport, with no damage or permanent deformation.
Pressure-sealed reservoirs shall be adequately designed for their maximum internal pressure during intended use. Corrosion protection
Any internal and external corrosion protection shall take into account
detrimental foreign contaminants, e.g. condensed water (SEE also Equipotential bonding
If required, equipotential bonding (e.g. grounding) shall be provided. Accessories When heaters are used, the heating power shall not exceed the manufacturer?€?s recommendations. If a heater is in direct contact with the hydraulic fluid, a low-fluid-level interlock may be provided. Thermal controls may be applied to maintain the desired hydraulic fluid temperature.
5.4.6 Piping system General requirements Dimensioning
Piping system conductor sizes and routing shall be designed taking into account the estimated fluid velocities, pressure drops and cooling requirements in all parts of the system under all anticipated operating conditions. It shall be assured that fluid velocity, pressure and temperature can be maintained within design limits throughout the system during all intended uses. Use of piping connections
The number of piping connections in the piping system shall be kept to a minimum, e.g. by use of bent tubing in preference to elbow connectors. Piping layout Tubes (i.e., rigid conductors) shall be used. Hoses may be used if required for accommodation of movements of parts, damping of vibration or reduction of noise. Piping shall be designed or guarded to discourage its use as a step or ladder. External loads shall not be imposed on the piping. Piping shall not be used to support components which can impose undue loads on the piping. Undue loads can arise from component mass, shock, vibration and pressure surges. Every connection to piping shall be sufficiently accessible to permit tightening with a torque wrench without, as far as feasible, disturbing adjacent piping or equipment. Design attention is particularly necessary where piping terminates in a cluster of connectors. Piping mounting and identification
Incorrect connections that can cause a hazard shall be avoided by identification of the tubes and hoses or by some other means.
Installation of hose assemblies shall
a) have the minimum length necessary to avoid sharp flexing and straining of the hose during assembly and operation; hoses shall not be bent at a radius smaller than the recommended minimum bending radius;
b) minimize torsional deflection of the hose during installation and use; c) be located or protected to minimize abrasive rubbing of the hose cover; d) be supported, if the weight of the hose assembly can cause undue strain. Protection against failure When failure of a hose assembly can constitute a whiplash hazard, the hose assembly shall be restrained or shielded by suitable means. If the failure of a hose assembly can constitute a fluid-ejection hazard or fire hazard, it shall be shielded by suitable means. If the above protection is not possible due to the intended mechanical movements, the information on residual risks shall be given. The information on residual risks may be used by the machine manufacturer for risk analysis and definition of necessary protective measures, e.g. technical measures such as the installation of piping explosion-proof valves or
instructions. Quick-action couplings The connection or disconnection of quick-action couplings under pressure shall be avoided. When such applications are unavoidable, quick- action couplings designed to connect or disconnect under pressure shall be used and detailed instructions for the operator shall be provided; SEE also Uncoupled quick-action coupling halves in a system under pressure shall be capable of either containing the full s...

View full details