Environmental Engineering Reference
In-Depth Information
figure 4.26 Coupling installation for all-metal hose.
clamp slides snugly over the hose and is then crimped tight by means of
a special hand tool or with an air-powered tool. Coupling for all-metal
hose, described earlier, involves two brazing operations, as shown in
Figure 4.26. The sleeve is slipped over the hose end and brazed to it, and
the nipple is then brazed to the sleeve.
Quick-connect, quick-disconnect hose couplings provide flexibility
in many plant process lines where a number of different fluids or dry
chemicals from a single source are either to be blended or routed to dif-
ferent vats or other containers. Quick-connect couplings can be used to
pump out excavations, manholes, and so forth. They would not be used,
however, where highly corrosive materials are involved.
4.11.5 hose Maintenance
All types of equipment and machinery require proper care and
maintenance, including hoses. Depending on the hose type and its appli-
cation, some require more frequent checking than others. The mainte-
nance procedures required for most hoses are typical and are outlined
here as an example. To maintain a hose, we should:
1. Examine for cracks in the cover caused by weather, heat, oil, or
usage.
2. Look for a restricted bore due to tube swelling or foreign objects.
3. Look for cover blisters, which allow material pockets to form
between the carcass and cover.
4. Look for leaking materials, usually caused by improper couplings
or faulty fastenings of couplings.
5. Look for corrosion damage to couplings.
6. Look for kinked or otherwise damaged hose.
Caution:
Because any of the faults listed above can result in a danger-
ous hose failure, regular inspection is necessary. At the first sign of
weakness or failure, replace the hose. System pressure and temperature
gauges should be checked regularly. Do not allow the system to operate
above design conditions—especially when hose is a component of the
system.
