LNG Tank Insulation Pillar Recess Gaps
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing heat-insulating elements for liquefied natural gas (LNG) tanks face challenges in managing thermal contraction, leading to stress and potential damage due to differential thermal expansion between the insulation material and the structural components, which can compromise the integrity and efficiency of the insulation.
Innovation Solution
The design incorporates a heat-insulating element with a thermal insulation lining made of a material capable of contracting more than its environment, such as low-density polyurethane foam, and features load-bearing pillars with recesses that allow for differential thermal contraction, accompanied by a flexible stuffing element to absorb deformations, ensuring the insulation remains effective and intact.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the thermal insulation lining is made of a material capable of significant thermal contraction (such as low-density polyurethane foam), then the thermal insulation performance is improved, but differential thermal contraction between the insulation material and structural components causes stress and potential damage
Solution Approach 1:
The thermal insulation lining is divided into multiple modular heat-insulating elements, each comprising independent pillars and insulation blocks. This segmentation allows each module to contract independently during thermal shrinkage, reducing stress concentration and preventing structural damage while maintaining effective thermal insulation performance.
Solution Approach 2:
The cross-sectional dimensions of the pillars are deliberately designed to be smaller than the recesses in which they are engaged at normal temperature, creating intentional gaps. These gaps accommodate thermal contraction by allowing the insulation material to shrink without generating excessive stress, thus preserving both insulation effectiveness and structural integrity.
2Force
If rigid pillars with fixed cross-sectional dimensions are used to bear compressive forces, then the load-bearing capacity is improved, but the rigid structure cannot accommodate thermal deformation of the insulation material
Solution Approach 1:
The connection between pillars and recesses transitions from a fixed rigid connection to a dynamic adjustable connection. The intentional dimensional mismatch creates gaps that allow the structure to adapt dynamically during thermal contraction, enabling the rigid pillars to maintain load-bearing capacity while accommodating thermal deformation through relative movement.
Solution Approach 2:
The design preemptively accounts for thermal contraction by creating gaps between pillars and recesses before thermal loading occurs. This preliminary design feature prevents stress buildup by allowing thermal deformation to occur within the available clearance, thereby protecting the rigid pillar structure from damage while maintaining compressive strength.
3Adaptability or versatility
If the cross-sectional dimension of pillars is reduced to allow thermal contraction gaps, then the adaptability to thermal deformation is improved, but the load-bearing capacity of individual pillars is reduced
Solution Approach 1:
Rather than using fewer large pillars, the design segments the load-bearing function across multiple smaller pillars. Each pillar has reduced cross-sectional dimensions to create thermal gaps, but the collective arrangement of multiple pillars distributes and maintains the required total load-bearing capacity, achieving both thermal adaptability and structural strength.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This solution effectively manages thermal contraction, reducing stress and maintaining the insulation's integrity, thereby enhancing the thermal performance and longevity of the insulating barrier in LNG tanks.
Implementation Method 1
a material capable of contracting more than its environment, when cooling, for example in a low density non-structural polyurethane foam
Implementation Method 2
The stuffing element is made of a material that is much less rigid than the thermal insulation lining so as to itself absorb most of the deformations induced by the different thermal contraction between the rigid structure and the thermal insulation lining
Data Source
AI summary
A lagging element suited to the creation of an insulating barrier in a sealed and insulating tank the lagging element comprising a flat cover panel, a thermal insulation lining (10) arranged parallel to the cover panel and load bearing elements which extend through the thickness of said thermal insulation lining from the cover panel to react compressive loadings, the load bearing elements comprising a plurality of pillars (4) the cross section of which is small in comparison with the dimensions of the cover panel and which are fit into recesses (11) in the thermal insulation lining and are fixed to the cover panel, in which, at normal temperature, a cross-sectional dimension of each pillar is smaller than a corresponding dimension of the recess in which the pillar is fitted. Application to the manufacture of a tank wall with a membrane for storing or transporting LNG.