Maintenance transfer hoses

In small plants and especially in those in which certain items of equipment have multiple uses, temporary connections are relatively common. Transfer hoses are often used to make such connections. This practice increases operating flexibility, reduces costs, and often helps to avoid cross-contamination between batches. However, it also presents new hazards in handling of the hoses, potential exposure to dangerous material, possibly wrong connections at hose switch stations, and more frequent leaks. The use of hard piping cormections is therefore preferable to the use of transfer hoses. If this is not practicable, there should be, at a mmimum, a conscientious program of replacement, inspection, maintenance, and proof of correct connection of hoses. 

Code of Practice No. 14, Hoses for the transfer of LPG in bulk. Installation, inspection, testing and maintenance. Code of Practice No. 15, Valve for LPG cylinders. Part 1. Safety valves for LPG cylinders. Part 2. Outlet valves for butane cylinders - quick coupling types Code of Practice No. 17, Purging LPG vessels and systems... 

The local fire department arrivedjust after the explosion at 11 22 A.M. With the limited water supply on two of the fire trucks and the utilization of another fire truck to pump water directly from a nearby cooling water tower basin, the firemen were able to slow the fire spread. By 11 30 A.M., the Maintenance Department was able to transfer the set of batteries from the impaired diesel fire pump to the other diesel fire pump. On completion of this task, this diesel fire pump was started. The automatic deluge sprinkler protection was severely damaged by the fire/explosions and had to be valved into the off position. Three fixed monitors were turned onto lull flow and directed at the fire. Also, the firemen and fire brigade used two hose streams olF nearby fire hydrants for fire fighting purposes. At 11 58 A.M., the fire was under control. Final fire extinguishment was accomplished by 12 10 p.m. 

The procedure was to clear the transfer fine of the waxy material with compressed air supply just before the transfer fine was put in service. On the evening of the accident, an operator connected an air hose to a 90 psig (6 bar) supply to clear the entire 200 meters (600 ft.) of feed line. The operator then walked to the elevated tank to determine if air could be heard rushing out of the tank vent. He heard nothing. The operator spoke to two maintenance employees working near the end of the 20-m3 (700 ft3 or 5,300 gallon) tank and left the area to find his supervisor. Shortly after that, one end of the tank blew off, and the two maintenance mechanics plunged some 40 ft. (12 m) to their deaths. [7]... 

Figure 7.12 shows a typical combination negative-positive pressure vacuum system. Vacuum from the pump draws material into either a cyclone separator or filter receiver. The pellets are passed through a rotary airlock and enter the blower discharge airstream, which is at positive pressure. The air/material mixture is transferred to the silos via stainless-steel flex-hose and fill lines. Combination units tend to be high-capacity systems used primarily with multiple silo systems. One advantage is that they require no equipment whatsoever on top of the silo, only a simple fill line. All maintenance is performed at ground level. 

Water supply is the safest bulk supply operation but it must comply with certain hygienic standards. Potable water tanks must be solely used for this purpose, maiataiaed under vessel s planned maintenance plan and audited under International Safety Management (ISM). Pumps and pipework should be flushed with super chlorinated water and than with fresh potable water prior refilling tanks. Hoses used for water transfer should be dedicated for this purpose and cleaned with chlorinated water on weekly basis. Each year hose need to be replaced. Water in potable water tanks of PSV typically may be stored for 7 da3 . After this time water is transferred to drill water tanks. Specific rules regarding water quality management usually are given in national regulations. 

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