Solving a Critical Application with Competence and Promptness

Connessioni & Tenute, a certified Fluid Connectors Parker distributor and assembler, supplied 600 connected, labelled, tested and packaged flexible hose pipe kits for the entire vehicle fleet of a well-known bus manufacturer. The analysis of the problem, study of the application and delivery of the supply were completed at record speed: less than two months.

by Silvia Crespi

A bus on fire is a sight we would never want to be faced with again. The memory of a couple of accidents that occurred in Milan in 2018 is still fresh, bringing to the forefront the theme of public transport conditions and their maintenance, two essential aspects for the health of both passengers and bus drivers. In both cases the fire broke out from the engine compartment, but the vehicles had just been re-tested. A careful analysis allowed to circumscribe the cause of the damage: as a result of vibrations and heat, the flexible hose pipes conveying the coolant were damaged, causing a loss of fluid on electrical components which, in turn, generated the short circuit, triggering the fire. To solve the problem, the manufacturer of the vehicles turned to a specialist in the field: Connessioni & Tenute, a company based in Pero, on the outskirts of Milan. Founded over thirty-five years ago as a company specialized in the supply of fittings for rigid and flexible hose pipes, today the company is a certified Fluid Connectors Parker distributor and assembler, capable of supplying sample hoses for both mobile and industrial applications. Connessioni & Tenute can rely on a ParkerStore, a point of sales dedicated to anyone having an immediate requirement to replace automation components or flexible hoses which may be manufactured immediately and to sample specifications.
Connessioni & Tenute can also provide the Hose Doctor service for maintenance assistance at the customer’s premises. Connessioni & Tenute is also active in the hydraulic and pneumatic sectors. The company supplies plants, such as hydraulic power units, for the most varied sectors: steelmaking, plastic and rubber processing, sheet metal machining to name but a few. “Our strength – Antonello Di Cesare, the company’s director, told us – lies in our ability to deal with every type of problem, from the simplest to the most complex, from hose pipe connections to plant management. And this is possible thanks to our thirty years of experience in the field of hydraulics”.

The first step: accurate analysis and identification of the cause of the problem
The first step in solving the problem was the technical analysis of the damaged hose pipe samples, carried out in synergy with both the vehicle manufacturer and the final customer. The analysis highlighted two critical issues: first of all, the excessive length of the hose pipe which brought it in contact with mechanical parts, causing early wear; secondly, the use of a rubber compound not suitable for the application, in terms of operating temperature and environment.
A technical report was therefore prepared taking into account the operating specifications and technical drawings, which had not been respected.

The solution: hoses in the right size made with appropriate compounds, supplied in traceable kits
Connessioni & Tenute therefore proposed an adequate solution: hoses in the right size, made with a rubber compound suitable for the application.
“The customer was provided with a first sample kit of tested hose pipes – Ivan Vanzini, sales engineer, pointed out – so that the manufacturer could carry out all the necessary checks by testing the hoses within the engine compartment.
Following this test, we made the necessary changes and, having defined everything, we began preparing the supply”.
In this application the same hose pipe model is used both for the endothermic engine cooling circuit and for the radiator fan control circuit connected to a hydraulic motor. A kit consisting of four hose pipes is assembled on each vehicle.
In this application the tube carries out a double function: it conveys the cooling liquid to both the radiator and the hydraulic motor. This is why a kit made up of four hose pipes is mounted on each vehicle.
Connessioni & Tenute has been entrusted with the supply of 600 revision kits, in total 2,400 original Parker hose pipes fitted according to specifications, labelled, tested and individually packed. Connessioni & Tenute also fitted all the hose pipes, a further demanding task carried out with success.
The company also acts as a certified fitting centre, using staff trained for this purpose, and can therefore provide a guarantee on the quality of the fitting itself.
In agreement with the vehicle manufacturer, it was decided to proceed with a check of all the vehicles in circulation where the pipes from previous suppliers were installed.

Traceability: the identity card of each individual pipe
The hose pipe kits were supplied with a PTS tag, a service offered by Parker to allow traceability.
Di Cesare explains: “Thanks to the PTS tag, each pipe is provided with a serial number. This system is also a great help in terms of predictive maintenance; in such applications it is essential to be able to replace the hose pipe before the fault occurs.
Traceability is also essential when vehicles are moved or sold in other cities or other countries.
Thanks to the traceability system every Parker distributor, in Italy and worldwide, is able to detect all the technical specifications of the hose pipe and its history, operation, working life, possible damages and so on.

A solution identified and refined at record speed
The time required to respond to the problem and solve it, prepare the supply and deliver it was the determining factor which represented the real added value in this critical application. “The speed and precision with which the diagnosis was made, and the capability to prepare the delivery in such a short time by Connessioni & Tenute – Marco Cattaneo, MarCom Leader at Parker, explained – represented the focus of this success story. “After this experience, the manufacturer certainly pays more attention to the products mounted on buses – Di Cesare concluded. For Connessioni & Tenute this has represented an important challenge, which it was able to face and win: we were supportive in all phases and we were able to establish a direct relationship with the Service of the manufacturer which, hope, will amplify our intervention potential”.