37 Installation, assembly, repair and maintenance of Pressure generating machines and machine parts, testing plants, gas compressing and regulating installations, machines for the metal, and plastic industry as well as automotive industry, namely, machines tools for processing, cutting, carving, grinding, milling, measuring, and testing of metal, and plastic, machine tools for processing, cutting, carving, grinding, milling, measuring, and testing of metal, wood, and plastic, for use in the metal, wood, plastic, automotive, aviation, shipbuilding industries, as well as for systems testing for operational and fatigue testing, Mechanical systems and appliances for high-pressure adjustments, primarily comprised of valves, pressure intensifiers, switching devices, switch panels, at least one drive unit and devices and appliances for protection against overloading, all of the aforementioned systems and appliances being parts of machines, structural and replacement parts for the aforesaid mechanical systems and appliances being parts of machines, mechanical systems for generating pressure comprised of valves, pressure intensifiers, switching devices, switch panels, at least one drive unit and valves for protecting against overloading and structural and replacement parts of said mechanical systems for machines, mechanical systems for solidifying surfaces, namely, autofrettage systems being metalworking machines, primarily comprised of the pressure generation system, the test chamber and the electric control cabinet, and structural and replacement parts therefor, Testing apparatus, devices, and instruments, namely, machines for testing components and systems made of metals and plastics with regards to functionality, energy-efficiency, leak-tightness, burst pressure, fatigue strength, resilience to internal pressure under varying temperature conditions of the testing medium and environment, not for medical purposes, Test benches and test systems being research laboratory analyzers for testing hoses and housings, for endurance and pressure tests, for burst pressure tests, for manometer tests, for gas compressors and control systems, for burst pressure tests, for fittings tests, for manometer adjustments and for pressure tests, Impulse testing systems comprised of a pressure generating unit and a test chamber as well as sensors, control unit, software and interfaces for testing the strength and durability of components or systems under pulsing pressure, Pressure cycling testing systems comprised of a pressure generating unit and a test chamber as well as sensors, control unit, software and interfaces for testing the strength and durability of components or systems under cycling pressure, Systems comprised of electronic apparatus for testing compression, strength, hardness and tensile characteristics of industrial materials, for determining the service life strength of components with high pressure requirements, electrical couplings, Pipes and tubes and parts of pipes and tubes all made of steel, stainless steel and metal being structural parts of land vehicles, water vehicles, air craft, power stations, as well as being structural parts for apparatus for locomotion by land, air or water, namely, common rail sub-systems, injection lines, injectors, steering column, tubes for bicycle frames, turned parts of metal as mechanical structural parts of land vehicles, water vehicles, air craft as well as being structural parts for apparatus for locomotion by land, air or water, Fuel distribution rails and lines for use in motors of land vehicles, water vehicles, air craft as well as apparatus for locomotion by land, air or water, couplings and power transmission components for use land vehicles, water vehicles, air craft as well as apparatus for locomotion by land, air or water