NOTA 8 ACTIVO FINANCIERO A VALOR RAZONABLE (5.11.20.00)
8.2 DERIVADOS DE COBERTURA E INVERSION
8.2.4 OPERACIONES DE VENTA CORTA
4.2.1.4.1 Operating Procedure of ASWM:
Before starting the machine, oil in power packs is to be checked. Check wash water temperature, whether wash pump valves are opened or not. Anode scraps are placed on the loading beam by crane. Wagon lifts the set and places it on the receiving conveyor. From the receiving conveyor scrap is transferred to the wash conveyor by a transfer device. Wash conveyor moves through wash chamber that consist two pipelines for washing, one on the topside and one at the bottom side. Each line is having seven nozzles through which water is sprayed on the scrap so that slime adhering to the scrap gets washed and goes to the tank. In the wash conveyor scrap moves horizontally and after washing it passes through dryer so as to wipe water from the scrap. From the wash chamber scrap is moved by stacker and stacks it on the stacking table. The stacking table rotates 900 anti clock wise after every two stack so as to make uniform bundle. Each stack consists of two scraps.
After completing the number of stack set in stack selector switch the table goes down. A set of fork comes in and takes away the bundle of scraps from the table to the stack conveyor.
From the stack conveyor forklift unload the bundle and keep it scrap yard. The scraps are weighed for individual banks to find out scrap % for the particular bank. Wash water temperature is maintained at 800C for effective washing. Temperature is maintained with help of steam. After one bank washing is over wash water with slime sent to storage tank and tank
36 IMPROVIG THE OPERATIOAL EFFICIECY AD PROFITABILITY OF EXPORT ORIETED UIT
is cleaned. Fresh water is filled for next washing. Machine is usually operated in auto mode.
It can be operated in manual and local mode when ever required.
FLOW DIAGRAM OF ASWM Scrap anode from cellhouse by crane
Washing
Stacking & bundling
To SMELTER for recasting as anodes 4.2.1.4.2 STADARD MACHIE HOURS REQUIRED:
The machine speed for ASWM is 350 anodes /hr.
Total no of SPENT ANODES in one bank =56anodes X 28 cells
= 1540 anodes
Standard time for washing spent anodes for one bank = 1540/350
= 4hrs 24mins
Major areas that cause the functioning delay for APM and the consolidated occurrence for the period of NOV’09-MARCH’10 is provided below:
AREAS TOTAL TIME PERCENTAGE
CUMULATIVE PERCENTAGE
WAGO 880 29.38230384 29.38230384
WASH COVEYOR 580 19.36560935 48.74791319
DISCHARGE COVEYOR 318 10.61769616 59.36560935
TD 305 10.1836394 69.54924875
STACKER 290 9.682804674 79.23205342
STACK TABLE 190 6.343906511 85.57595993
COTROL PAEL 125 4.173622705 89.74958264
MISCELLAEOUS 100 3.338898164 93.0884808
RECEIVIG COVEYOR 97 3.238731219 96.32721202
FLAPPER 75 2.504173623 98.83138564
WASH CHAMBER 35 1.168614357 100
TOTAL 2995
Table 4.5
37 IMPROVIG THE OPERATIOAL EFFICIECY AD PROFITABILITY OF EXPORT ORIETED UIT
4.2.1.4.3 PARETO AALYSIS:
Fig 4.7
In ASWM the most common area where the majority of the problems occur is wagon. Of the total delay time wagon has the largest share. Some of the common and frequently occurring problem in wagon area is:
1. Loading wagon hoist not working.
2. Loading wagon trolley damaged.
3. Anode stucked at unloading wagon.
4. Unloading wagon home position sensor malfunctioning.
Secondly, the wash conveyor area is more prone to malfunction and cause the delays. Some of the commonly occurring delays in wash conveyor are:
1. Wash conveyor stuck up.
2. Wash conveyor link got broken.
3. Weak scrap stucked @ wash .conveyor.
0 10 20 30 40 50 60 70 80 90 100
WAGON WASH CONVEYOR DISCHARGE CONVEYOR TD STACKER STACK TABLE CONTROL PANEL MISCELLANEOUS RECEIVING CONVEYOR FLAPPER WASH CHAMBER
Series1 Series2
38 IMPROVIG THE OPERATIOAL EFFICIECY AD PROFITABILITY OF EXPORT ORIETED UIT
The delay problems are also divided among the departments as mechanical, electrical, process, instrumentation and cranes. The consolidated delay distribution of the departments from NOV’09-MARCH’10 is pro
As we see in the Pareto chart, the major delay occurs in the process. Some of the process
1. Stacker- Week scraps stucked at stack table.
2. Wash conveyor- Week scrap stucked at wash conveyor.
3. Receiving conveyor- Bridge broken
4. Stack Table- Week scrap stucked at stack table.
5. TD- scraps continuous fallen in TD.
The second major cause of delays comes under mechanical. Some of these delays are:
1. Wash conveyor- Wash conveyor link got cut.
2. Stacker- Flapper topside guider got bent.
3. Wash conveyor- wash conveyor guider bent.
0
IMPROVIG THE OPERATIOAL EFFICIECY AD PROFITABILITY OF EXPORT ORIETED UIT
The delay problems are also divided among the departments as mechanical, electrical, process, instrumentation and cranes. The consolidated delay distribution of the departments
MARCH’10 is provided below:
As we see in the Pareto chart, the major delay occurs in the process. Some of the process delays are:
Week scraps stucked at stack table.
Week scrap stucked at wash conveyor.
Bridge broken scrap stucked at receiving conveyor.
Week scrap stucked at stack table.
scraps continuous fallen in TD.
The second major cause of delays comes under mechanical. Some of these delays are:
Wash conveyor link got cut.
Flapper topside guider got bent.
wash conveyor guider bent.
MECHANICAL ELECTRICAL INSTRUMENTATION
IMPROVIG THE OPERATIOAL EFFICIECY AD PROFITABILITY OF EXPORT ORIETED UIT
The delay problems are also divided among the departments as mechanical, electrical, process, instrumentation and cranes. The consolidated delay distribution of the departments
CUMULATIVE
As we see in the Pareto chart, the major delay occurs in the process. Some of the process
scrap stucked at receiving conveyor.
The second major cause of delays comes under mechanical. Some of these delays are:
INSTRUMENTATION
Series1 Series2