Nova-Tech LMI Series G - SG Metering Pump - Manual (Page 22)

16
bevel should not face the inside of the check valve
(refer to Figure 14A or 14C). Use a flat surface
such as a board to press the seat into the ball
guide with firm, even pressure.
THE ORDER OF ASSEMBLY AND ORI-
ENTATION OF THE SUCTION AND DIS-
CHARGE CHECK VALVES IS
DIFFERENT. REFER TO FIGURE 8, 10,
12, 14A, AND 14C FOR PROPER
ASSEMBLY ORDER AND ORIENTA-
TION. IF CHECK VALVE CARTRIDGES
ARE INSTALLED INCORRECTLY, ONE
OF THE FOLLOWING WILL OCCUR: (A)
IMMEDIATE SEVERE DAMAGE TO
PUMP MECHANISM, (B) NO PUMPING,
(C) REVERSE PUMPING ACTION
(FROM DISCHARGE LINE INTO SUC-
TION LINE).
4. Position the union end (445) onto the correct
end of the ball guide. Refer to Figure 14A or 14C,
as the correct end is determined by whether the
valve is intended for the suction or discharge port
of the liquid end. Slip the union nut (435) over the
union end and screw tightly (hand tight only) onto
the ball guide.
5. Screw the valve assembly into the liquid end
body
(hand tight only). DO NOT OVER
TIGHTEN.
4.4.1.2 Models SG6 & SG7 Liquid Ends - Stain-
less Steel Check Valves (Figure 14D):
Disassembly
1. Unscrew the three screws (441 & 442) and
remove them and their three washers (439).
2. Remove the valve clamp (437).
3. The connection (435), seat (420), ball (422)
and ball guide (424) should all now slip apart eas-
ily.
4. Remove and discard the three gaskets (419).
5. Carefully clean any parts to be reused. If any
chemicals are used in the cleaning process,
ensure that they are compatible with the process
liquid.
Reassembly
1. Drop the ball into the curved inner chamber
end of the ball guide.
DO NOT REUSE OLD GASKETS (419).
EVEN IF BALL AND SEAT ARE NOT
WORN AND DO NOT NEED REPLAC-
ING, NEW GASKETS MUST BE USED
ANY TIME THE CHECK VALVES ARE
DISASSEMBLED.
2. Place a new gasket on the rim of the ball guide
(424), and sit the seat on top of the ball guide, trap-
ping the ball and gasket between the seat and ball
guide.
THE ORDER OF ASSEMBLY AND ORI-
ENTATION OF THE SUCTION AND DIS-
CHARGE CHECK VALVES IS
DIFFERENT. REFER TO FIGURE 11, 13,
AND 14D FOR PROPER ASSEMBLY
ORDER AND ORIENTATION. IF CHECK
VALVE CARTRIDGES ARE INSTALLED
INCORRECTLY, ONE OF THE FOLLOW-
ING WILL OCCUR: (A) IMMEDIATE
SEVERE DAMAGE TO PUMP MECHA-
NISM, (B) NO PUMPING, (C) REVERSE
PUMPING ACTION (FROM DISCHARGE
LINE INTO SUCTION LINE).
3. Position the connection (435) onto the correct
end of the ball guide with a gasket trapped
between the two metal surfaces. Refer to Figure
14D, as the correct end is determined by whether
the valve is intended for the suction or discharge
port of the liquid end.
4. Position the check valve assembly onto the liq-
uid end, trapping a gasket between the two metal
surfaces (seat and pump head).
5. Slide the valve clamp (437) over the connec-
tion (435) and screw into the liquid end using the