GB/T 26148-2025 Safety specification for the use of manually operated high pressure waterjet equipment
1 Scope
This document specifies the composition and requirements of work teams, pre-operation preparations, operational procedures, and equipment maintenance for high pressure waterjet cleaning operations.
This document is applicable to high pressure waterjet cleaning operations with working pressures not less than 10 Mpa, with reference for waterjet mobile cutting and demolition operations.
2 Normative references
The following documents contain provisions which, through reference in this text, constitute provisions 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.
GB 14866 General technical specification for eye and face protector
GB/T 41513 Classification and terms for jet equipment
AQ 3018 Safety rules for works at the district of storage tank for dangerous chemicals
AQ 3026 Safety code for equipment repair in chemical manufactory
HG 30010 The safety code for hot work in workplace
HG 30011 The safety code for confined spaces in workplace
HG 30013 The safety code for working at heights in workplace
3 Terms and definitions
For the purposes of this document, the terms and definitions given in GB/T 41513 and the following apply.
3.1
high pressure pump
pressure source equipment used to increase water pressure and deliver high pressure water to the nozzle, with a working pressure range of 10 MPa to 100 MPa
Note: High pressure pumps typically adopt positive displacement plunger pump configurations to ensure constant flow rate at a given pump speed.
3.2
spray gun
handheld cleaning tool that controls high pressure water to form waterjet through nozzles
Note 1: It consists of a control valve, lance, and nozzle assembly (including one or multiple nozzles). The spray gun locking mechanism is shown in Figure 1.
Note 2: The spray gun is typically connected to the pressure regulating valve at the discharge end of the high pressure pump via the high pressure hose assembly.
Note 3: Spray guns can be classified by control valve type: When the valve is closed, system pressure drops to ambient level, and high pressure water is discharged to the atmosphere; when the valve is closed, high pressure water remains retained in the system.
[Source: GB/T 41513-2022, 4.3.6, modified]
Key:
1——Shoulder rest;
2——High pressure hose assembly;
3——Trigger guard;
4——Locking mechanism;
5——Control valve;
6——Trigger;
7——Lance;
8——Nozzle assembly;
Figure 1 Spray gun
3.3
flexible lance
waterjet tool formed by connecting the pump to the nozzle (spray head) via flexible pipe, controlled by a foot-operated valve
[Source: GB/T 41513-2022, 4.3.11, modified]
3.4
rigid lance
waterjet tool formed by connecting the pump to the nozzle (spray head) via rigid pipe, controlled by a foot-operated valve
[Source: GB/T 41513-2022, 4.3.12, modified]
3.5
high pressure hose
flexible pipe for transferring water between components of high pressure waterjet unit
3.6
high pressure waterjet unit
equipment that performs jetting operations through waterjets
Note: Solid particles or chemical additives may be added into the waterjet, and the temperature may also be risen. High pressure waterjet units are commonly used for engineering operations such as cleaning, coating removal (rust, paint, adhesives, etc.), fragmentation, and cutting. It generally consists of: high pressure water generation equipment (typically high pressure pump units or pressure intensifier units), control system [including safety pressure relief devices, pressure regulating valves (overflow unloading valves), control valves, electrical control cabinets, operator consoles], actuating mechanisms (components including spray guns, nozzles, abrasive jet assemblies, and feed mechanisms), and auxiliary systems (instrumentation, piping, mounting equipment, protective devices, etc.).
[Source: GB/T 41513-2022, 4.1.1, modified]
3.7
hose assembly
component consisting of high pressure hoses and corresponding end fittings
Note: Each end fitting of the hose shall be professionally crimped and pressure tested.
[Source: GB/T 41513-2022, 4.3.25, modified]
3.8
flex ring
short steel cable or looped wire connected to hose end fittings, designed to prevent whipping or uncontrolled movement of the hose end in case of sudden fitting failure or disconnection
Note: Also referred to as flexible restraint, safety lanyard, or safety coupling.
Example: See Figure 2.
Figure 2 Flex ring
[Source: GB/T 41513-2022, 4.3.27, modified]
3.9
hose safely shroud
flexible shroud installed over hose assemblies, typically covering end fittings or spray gun connections with specified length, designed to shield operators from high pressure water jet exposure during hose ruptures, threaded fitting failures, or leakage from drainage ports
[Source: GB/T 41513-2022, 4.3.26, modified]
3.10
feed device
specialized mechanical device for operating nozzle movement, enabling the nozzle to approach cleaning targets while achieving all or partial functions including nozzle feed and retraction inside pipes, as well as vertical, horizontal, tilted, rotational, and articulated arm movements during nozzle advancement in tanks
Note: Examples include robotic arms, manipulators, pipe rotators, and dedicated cleaning mechanisms.
[Source: GB/T 41513-2022, 4.3.28, modified]
3.11
operator
individuals who have undergone training and demonstrated competency in equipment installation, control, operation, and maintenance
3.12
cleaning field
entire field where cleaning operations are conducted, demarcated with warning signs and protective railings
3.13
reactive force
reactive force generated during waterjet formation by discharge components
3.14
anti-withdrawal device
device installed at pipeline access points to prevent pressurized nozzles attached to hose ends from being forcibly expelled from the pipeline during operation
Note: The outline drawing of anti-withdrawal device is shown in Figures 3 to 6.
1 Scope 2 Normative references 3 Terms and definitions 4 Composition and requirements of cleaning team 5 Pre-operation preparations 6 Operational procedures 7 Equipment maintenance Annex A (Informative) Color identification for distinguishing pressure levels of high pressure hoses Annex B (Informative) Safety protective equipment for high pressure waterjet cleaning operations Appendix C (Informative) Emergency response card for high-pressure injection injury Annex D (Informative) Safety checklist prior to high pressure waterjet cleaning operations
