Crimping a Chemical Hose
What does crimping a chemical hose assembly mean? Chemical hose crimping is the process by which a chemically resistant hose tube and cover has a metal ferrule or sleeve compressed against it with a measured set of die pieces. This prepares the chemical hose assembly for use by forming an industrial seal between the hose fitting, hose tube, and ferrule or sleeve.
Why make sure your hose is crimped? Crimping a hose has become the prevailing process for finishing any hose assembly in the industrial marketplace. For a chemical transfer hose assembly, correctly completing the hose crimp is arguably an even more important part of the quality control process. Imagine an acid resistant hose is crimped incorrectly or mistakenly not crimped at all. While the faulty hose assembly may be physically able convey the acidic media at lower pressure, over time the chances of failure increase to an unsustainable risk level. Whether that failure occurs in a forceful unintentional disconnection between the fitting and hose tube during the operation, or in leakage during the chemical conveyance process where an environmental hazard event is created, the situation is dangerous for all involved.
Whether you work with Hose Fab Shop or a separate chemical hose supplier we strongly recommend ensuring your hose is correctly crimped before installation. This quality control measure reduces inefficiencies, increases safety of your chemical transport system, and prevents leakage of the media being conveyed over the working life of your transfer system.
How is the crimping process completed? To complete the crimping process for a chemical hose assembly our specialists will select the appropriate tube, cut the hose to a requested size, and identify the needed fitting configuration. If applicable, our hose assembly technician will select the correct gasket type based on customer request or communication with the customer on needed application. (Always consider letting us know the details of your application so that we can create a customer chemical transfer hose designed for your exact need).
The end of the cut hose is then cleaned and flattened to ensure a flush fit. The hose is then marked for the fitting and if applicable, grounded with tubing wire. The ferrule or sleeve is placed over the cut hose end and the fitting is lubricated and then inserted.
Our specialists open the jaw of the crimping machine and select the correct die size for the hose being crimped. After the correct die is chosen it is loaded onto the crimping machine and the jaw is closed with the die pieces locked. The hose is placed on the die and the machine’s cylindrical collar moves in to crimp the ferrule or sleeve with the hose tube and fitting. After the collar is released, the specialist will inspect the hose to make sure the hose fitting’s position did not move during crimping.
After the crimping process the full chemical hose assembly should be pressure tested to ensure there are no manufacturing issues and that the crimping process was completed correctly. At Hose Fab Shop every one of our chemical hoses is tested by one of our specialists onsite.
What about banded or field made chemical hoses? While band clamped hoses were used for years, this practice is no longer considered a safe for use with chemical hoses. Over the years, many spills we caused by improperly installed clamps, or clamps that had worn and loosened with age. This type of coupling attachment method should be used only for non-critical water applications.