Company Description

AFRY erbjuder tjänster inom teknik, design, digitalisering och rådgivning. Vi är hängivna experter inom industri, energi- och infrastruktur, som skapar värde för kommande generationer. AFRY har en global räckvidd med djupa rötter i Norden. Tillsammans accelererar vi omställningen till ett mer hållbart samhälle.

Job Description

Detailed nonlinear analysis of bolted joints 

Background

Bolted joints provide a convenient and universal means of joining components and structures.  For bolted joints, the intent of the assembly process is to apply a torque to the fastener in order to generate sufficient clamp load such that the joint will maintain integrity over the intended usage and life of the component or system. The relationship between the applied torque and the clamp load is a function of fastener sizing and selection, and the tribological interactions at the sliding interfaces of the fastener.

Objective

Within the thesis project a detailed finite element model of a bolted joint should be developed in order to study the friction behaviour at the sliding interfaces, under head- and thread interfaces while tightening and loosening the fastener. The analysis should investigate the torque-angle-clamp behaviour during various phases of the operational life of a joint.  This includes the initial tightening of the joint, subsequent incremental tightening and loosening of the joint.

Methods

Initially a literature study should be conducted to find current industrial practice and existing methods for detailed bolt modelling and its tribological effects. Test results of torque-angle-clamp data should be studied to understand the physical behavior of the joint and to develop a representative FE model. Once an FE model is created, set up analyses to study how various parameters will affect the results. Since torsional stress and clamp load will be affected by change in parameter such as friction, clamping length and material characteristics.

Deliverables

A report containing:

• Literature study of bolted joints and its tribological effect

• Guidelines for FE modeling of a representative model with sliding behaviour

• Result of correlation with respect to torque-angle-clamp test data
• Result of friction variation studies regarding torsional stress and clamp load
• Discussion of results and implications to joint design

Qualifications

Master Programs: Applied Mechanics or equivalent

Additional Information

AFRY is a European leader in engineering, design, and advisory services, with a global reach. We accelerate the transition towards a sustainable society. We are 19,000 devoted experts in infrastructure, industry, energy and digitalization, creating sustainable solutions for generations to come.

In the department CAE & Vehicle safety, in Trollhättan, you will be part of the team that performs strength, durability and NVH analysis to develop the performance and attributes of vehicles and systems of the future. Our customers are both local and international.

Selection is ongoing with a deadline for applications.2025-10-31

Contact

Annika Aleryd, annika.aleryd@afry.com

Lisa Kilsmark, lisa.kilsmark@afry.com

At AFRY, we engineer change in everything we do. Change happens when brave ideas come together. When we collaborate, innovate technology, and embrace challenging points of view. That’s how we're making future. We are actively looking for qualified candidates to join our inclusive and diverse teams across the globe. Join us in accelerating the transition towards a sustainable future.