Tee crotch


The EN 13480-3 scope is specified as ‘the design and calculation of industrial metallic piping systems, including supports. The design criteria, as laid out in clause 4, include the internal and/or external pressure amongst others

EN 10253-2 calculations

The dimensions standard EN 10253-2 (and also EN 10253-4) have further detailed the calculations of EN 13480-3. The EN 10253-2 calculations are based on the EN 13480-3 but tailored to the EN 10253-2 fittings.The fitting types are elbow, tee, reducer and cap. The calculations are now part of our E80 application.

There are cases with manhole blind flanges where the number of bolts are not enough for a proper leak tight connection with the flange at the storage tank side. The blind flange takes the shape as an ‘umbrella’ around the bolts.

This document is for discussion, comments and suggestions. The purpose is to demonstrate the dimensions of the 42” 150# flange in relation to bolt load requirements for leak tightness. The 300# flange is used to illustrate the differences and the cause for possible tightness problems in case a spiral wound gasket is used

This article informs about the letter sent from Red-Bag to the ASME B31.3 committee subgroup materials SG-D.


This document is for discussion, comments and suggestions. The purpose is to compare and validate the EN 10253-2/4 strength calculation in B.4.4 and B.5.3 with the EN 13480-3 Clause 8. The EN 10253-2/4 indicate that the calculations are based on the EN 13480-3. This document highlights possible differences.

There is sometimes confusion about the joint efficiency when you compare the ASME B31.1 and the ASME B31.3. The joint efficiency for the ASME B31.1 (2020) are included in the allowable stress values of Table A-1 (US Customary units). Be careful, because some tables are also available is SI or metric units.

EN 13480-3 Clause 7.2.3 Possible ambiguous result

Red-Bag is member of the CEN/TC 267/WG3 workgroup. This workgroup is responsible for the maintenance and improvements of the EN 13480-3 Industrial Piping and Pipelines standard.

Red-Bag is developer and provider of software for the calculation according the EN 13480-3. The software is used by Notified Bodies to assess the validity of the engineering calculations submitted by plant owners, engineering companies and manufacturers.

The international customer base is growing in all Spanish speaking countries including Spain in Europe and especially the countries in South America. Our goal is to provide easy communication for our customers. We are happy to announce that Red-Bag has an agent in Spain with whom customers can communicate in the Spanish language. Use this Spanish contact form to contact our agent.

Flange bolt unloading

Many of us have the impression that the bolt stress will go up when a flange pair in a pipe system is pressurized after assembly.

Red-Bag User Day May, 2019 took place in the new industrial location of RDM Rotterdam. We have had a successful start of the Technical Journey with a motivated group of participants.

We are happy to announce that our new address is:

Red-Bag BV
Klinknagelstraat 2
3089 JP Rotterdam

Tel.: +31(0)10 790 0062
New VAT nr.: NL859323808B01

All relevant contact and email addresses remain the same. Contact us at Esta dirección de correo electrónico está siendo protegida contra los robots de spam. Necesita tener JavaScript habilitado para poder verlo..

Red-Bag User Day April 12, 2017 - Delft  - The former industrial building of Lijm & Cultuur created a splendid technical environment for technical presentations and sharing experiences.

EN1591-1 Training

To get an impression of the software click here ...

Training skid of Dijkgraaf-Suport is being unloaded at the User Day site. We have received very positive feedback and will have more of these User Days in the future. We thank all participants and especially thank Peter Dijkgraaf and Cyril Wentzel for their excellent contribution.

Invitation User Day 2016

Red-Bag is conducting a user day on April 5, 2016 in Rotterdam. The registration is open for users of the Red-Bag software. The registration is closed, 2016.

The main purpose is to meet other colleagues and to share experience.

Design and engineering requires hands-on experience. The engineering calculations are difficult to assess without this experience. Although Red-Bag is a software company we believed this experience is crucial to giving adequate support to our customers. Red-Bag is finalizing the calculation software as per EN1591-2014. This calculation method is very detailed and complex. The Red-Bag software engineers together with engineers of Gasunie followed the course of flange management at Dijkgraaf-Support B.V. The images give an overview of the practical exercises supporting the theory as presented in the class room.

Red-Bag is conducting a training - November 16, 2016 in Delft.

We are happy to announce that the latest release of the Vessel & Exchanger Software version 8.4 August 2014 has been issued. The package will be send to our customers this week. Customers receive this software update as part of your maintenance contract.

Below listed are the major updates.

Fluor Netherlands is using the PCC software of Red-Bag for the calculation of their pipe class components. During the years Fluor has provided valuable feedback for the further development of the software and the cooperation has been successful ever since.