The quality mark pipe supports
The RAL quality mark "pipe supports" is awarded solely to products that fully fulfil the high requirements and standards of RAL quality assurance.
These requirements are defined in the Quality and Test Regulations RAL-GZ- 655.
Technical testing is carried out by an approved and independent test institute. Consequently, the technical details of quality assured pipe supports do not simply present subjective information provided by the manufacturer, but are verified by impartial test institutes. To ensure uniform across-the-board product quality, quality assured pipe supports are additionally subjected to regular inspections.
As a result, the quality mark "pipe supports" offers certainty and orientation when selecting a pipe support.
The following national and international test institutes are approved in accordance with RAL-GZ 655 and able to verify appropriate levels of experience in carrying out initial tests and monitoring inspections.
- Materialprüfanstalt (MPA) für das Bauwesen – Civil Engineering Materials Testing Institute, Braunschweig, Germany
- Kiwa Netherlands B.V., Rijswijk (NL)
Pipe supports are often mass produced products. It is hugely important that the desired product characteristics are reliably guaranteed even when large batch quantities are involved. Consequently, that means it is essential that the manufacturer's quality assurance programme is efficient.
That in turn means manufacturers of quality assured products must implement particularly effective, verifiable monitoring and inspection regimes. Before a pipe support is approved for an initial assessment, the manufacturer must prove his qualification and commitment to carry out effective in-house inspections. It is not possible to award any product of the manufacturer a quality mark without this proof. The manufacturer is also obliged to carry out these in-house monitoring and inspections regularly and correctly.
Trust & reliability
Effective quality assurance and in-house monitoring and inspections are certainly an important instrument for a manufacturer of premium products. However, this alone is not sufficient to be awarded the RAL quality mark "pipe supports". Implementing initial tests and regular external monitoring carried out by an accredited, independent test institute is an essential component of the quality assurance standard RAL-GZ 655.
This impartial assessment of the products effectively guarantees that the details contained in the manufacturer's catalogue are not simply the manufacturer's own subjective details, but are impartially examined, reliable and comparable details.
It is the combination of continuous in-house monitoring and inspections by the manufacturer and continuous monitoring by external institutes that create the basis for the trust that characterises the RAL quality mark.
A complete set of technical standards were drawn up that contain clear and unambiguous processes to determine the mechanical technical data of pipe supports. These guidelines are a core component of the quality assurance standard RAL-GZ 655 "pipe support" published by RAL, the German Institute for Quality Assurance and Certification. Prior to their publication the relevant specialist committees and working groups involved subjected these codes of practice to close scrutiny.
The described assessment procedures were recognised as proper and appropriate. The technical data determined on the basis of these procedures are reliable and comparable. The RAL quality mark "pipe supports" identifies products whose technical standard has been determined on the basis of these recognised procedures.Download quality mark RAL-GZ 655
Pipe clamps »
Pipe clamps are the heart of any pipe support. They are virtually omnipresent in the field of installation technology. Unfortunately, some decision makers make very little effort to look into the special features of pipe clamps.
The pipe clamp serves as a classic example to illustrate necessity for a uniform, reliable and comparable assessment.
Fundamentally, it is possible to determine two variables:
- clamp deformation under an imposed load.
- clamp failure under an imposed load.
The latter is the classic detail regarding pipe clamps. It is possible to observe both variables in a force-displacement curve:
Pipe clamp on a test stand
The classic assessment of a pipe clamp only takes its fracture behaviour into consideration. However, the fracture load can fluctuate from specimen to specimen. Even the method of taking this distribution into consideration can result in different technical data.
It is clear that manufacturer-specific procedures cannot provide comparable values. In addition to its fracture load, the expected deformation of a pipe clamp under an imposed load in particular is an extremely significant factor when determining fitness for purpose. Many traditional manufacturer assessment procedures do not take this deformation sufficiently into consideration or not at all.
The method used to determine the allowable load acting on a pipe clamp taking into consideration the fracture load and deformation is clearly defined in RAL-GZ 655 Part B. Proven and recognised statistical methods that take the distribution of values into consideration are applied. As a result the technical details of quality assured pipe clamps offer a particularly high level of certainty and fitness for purpose.
Mounting rails »
RAL-GZ 655 Part C summarises the relevant regulations that apply to mounting rails used to secure pipes. Mounting rails are the most versatile components used to secure pipes. They make it possible to implement widely different solutions for practically all pipe fixing tasks.
Using a mounting rail in professional solutions without knowledge of its mechanical characteristics is fundamentally not acceptable. The principle technical details of a mounting rail that must be known before it is installed are the material from which it is made, the yield point, moment of area values (moment of inertia) and details regarding moment of resistance.
Mounting rail accessories / connection designs
The availability of mounting rail accessories such as rail connectors and angle sections makes mounting rail solutions extremely versatile. Solutions on offer include complete construction systems, which means the interaction between the individual components is of particular significance.
RAL-GZ 655 Part D contains the relevant procedures to assess assembled combinations of components. When it is possible to describe combinations of connection types and the respective mounting rails using common technical data, the combinations are known as "connection designs". The relevant technical data of quality assured connection designs is determined by an impartial body based on this assessment standard.
In addition to the usual technical data two new values are determined for brackets awarded the quality mark pipe support: the yield moment and the associated maximum lever arm for design purposes factoring in the yield moment. Both values make it possible to quickly select a suitable product for installation on site.
Of course it is still possible to select a bracket on the basis of traditional calculation. However, when using brackets the substructure on which the brackets are mounted should always be taken into consideration. It is necessary to select appropriate, sufficiently sized fixing systems (e.g. wall plugs) depending on the substructure in question. The type of substructure can have a significant influence on the forces that need to be taken into consideration. The relevant assessment methods are contained in RAL-GZ 655 Part E.