Preheating & Welding
Controlled heat for secure welds
Our range of services in the field of switchgear and power distribution
Professional preheating before and during welding is a crucial factor for the quality and safety of a welded joint with many materials and components.
GRUBE offers high-performance solutions for the controlled preheating of pipelines, tanks, welds, and industrial components. Depending on the material, component geometry, and technical requirements, different electrical heating methods are used.
Through precise and uniform temperature control, we create optimal conditions for the subsequent welding process – directly at the customer's site, on construction sites, during overhauls or within complex industrial plants.
Why is preheating important when welding?
Reduction of thermal stresses
Smaller temperature differences between the weld zone and the base material can reduce the formation of critical stresses.
Controlled cooling rate
Welding creates thermal stresses in the material due to the locally very high temperatures and subsequent cooling. At the same time, the material's properties can change, particularly in the weld area and the heat-affected zone.
Reduced risk of cold cracking
Controlled temperature management plays a particularly important role in high-strength and crack-prone steels.
Improved welding conditions
Defined preheating and interpass temperatures support reproducible welding processes.
Fulfillment of technical specifications
Temperature control can be carried out according to welding instructions, material requirements and project-specific specifications.
Preheating with electrical resistance heating
Electrical resistance heating allows for targeted heat application directly at the component.
Flexible heating elements are attached to pipes, welds, flanges, tanks, or other components according to their geometry. Suitable thermal insulation reduces heat loss and promotes a more homogeneous temperature distribution.
The process is particularly suitable for local heat treatments and can also be used flexibly with complex geometries.
Depending on the project, GRUBE takes over the complete technical implementation – from the preparation and installation of the heating elements to temperature measurement and monitoring of the preheating process.
Preheating with induction
Efficient heat input for demanding applications
In addition to resistance heating, inductive preheating can be a particularly efficient method for the controlled heating of metallic components.
In induction heating, heat is generated directly within the material. This allows components to be brought to the required temperature quickly and precisely.
Especially for pipelines, larger wall thicknesses and recurring welding processes, the method offers interesting possibilities in terms of speed, controllability and energy input.
Preheating of pipelines and welds
Pipelines are among the classic areas of application for controlled preheating.
Depending on the diameter, wall thickness, material, and welding process, the heating elements are positioned around the intended welding zone. The required temperature can be monitored via multiple measuring points.
This allows not only the necessary preheating temperature, but also the required interpass temperature during welding to be controlled.
Typical areas of application include power plants, refineries, petrochemicals, plant engineering, pipeline construction and industrial production facilities.
Temperature control during welding
The decisive factor is not simply reaching a certain temperature.
The temperature must be correct where it is required for the welding process.
GRUBE therefore relies on controlled temperature measurement and regulation. Depending on the project requirements, several measuring points can be used on the component.
This allows preheating temperature, interlayer temperature and temperature profile to be monitored and documented if necessary.
Preheating for power plants and petrochemicals
Especially in power plant construction, refineries and petrochemical plants, high demands are placed on welded joints.
Large wall thicknesses, demanding materials, and defined welding and heat treatment processes require precise temperature control.
GRUBE supports new construction, maintenance, repair and overhaul projects with mobile solutions for preheating and subsequent heat treatment.
Preheating and PWHT from a single source
Preheating often doesn't end with the final welding pass in demanding welding tasks.
Depending on the material, wall thickness and technical specifications, further heat treatment may be necessary after completion of the welding work.
GRUBE therefore combines Pre-Heating and Post Weld Heat Treatment (PWHT) into a comprehensive heat treatment concept.
This enables a controlled process from the preparation of the welding point through preheating and monitoring of the welding process to the subsequent heat treatment.
PRE-HEATING → WELDING → PWHT
One contact person for the entire thermal process.
Preheating directly on your construction site
Our systems are designed for mobile use. This allows heat treatments to be carried out directly where welding is taking place.
Whether it's a power plant, refinery, petrochemical plant, pipeline project, tank construction or industrial overhaul – our teams and facilities can be deployed on-site on a project basis.
Even components that are difficult to access and complex geometries can be processed with appropriately adapted heating and insulation concepts.
More than 50 years of experience in heat treatment
Since 1974 , Wärme- und Glühtechnik GRUBE GmbH has stood for professional industrial heat treatment.
Today, our experience is combined with modern plant, measurement and control technology as well as a highly qualified team.
Our customers benefit from:
More than 50 years of experience · international project experience · mobile PWHT · resistance annealing · induction annealing · mobile annealing furnaces · high-performance measurement and control technology · qualified specialists · 24-hour personnel service
Experience, technology and controlled processes
Professional preheating means more than simply heating a component.
Crucial factors are the right heating technology, suitable positioning of the heating elements, sufficient insulation, and controlled and traceable temperature management.
GRUBE combines many years of experience in industrial heat treatment with high-performance technology and flexible solutions for a wide variety of operating conditions.
Your project. Our heat treatment.
Do you need assistance with preheating pipes, containers, or other components before welding?
Speak to our specialists.
Together we develop a suitable solution for material, component geometry, welding process and the respective project requirements.
