The D/A MM6UC is a universal mounting 3-valve manifold that performs all the necessary functions of a 3-valve system by utilizing two 3-way valves working together instead of 3 independent 2-way valves. This sensible concept allows the operator to dial the desired function rather than manipulating a cluster of independent valves. The unique design of the UNIMOUNT properly groups and interlocks the porting to provide automatic fool-proof sequencing, drastically reducing the costly errors of improper operation inherent in 3-valve systems.
This same unique manifold excels in the ability to perform as both a manifold and a sturdy transmitter mount for systems that require remote mounting to a 2" pipe, direct mounting to the meter run flanges and direct mounting to an integral orifice block.
The Unimount design allows the completion of all piping prior to installation of the transmitter. The built in manifold mounting system permits easy removal of the transmitter without disturbing the process lines or mounting connections.
The D/A UNIMOUNT - A Truly Universal Instrument Adding an Extra Dimension of Simplicity, Convenience and Safety to Manifolding Practices.
Direct Mounting to Meter Run Flanges
Direct Mounting to Integral Orifice Block
Remote Mounting to a 2" Pipe
With both valve handles in the normal position, the MM6UC is in the normal mode with both process inlets open and the equalizing port blocked.
By dialing the Zeroing Valve handle to the ZERO position, the MM6UC is automatically switched to the zeroing mode which completely and properly prepares the transmitter for zeroing by (1)first blocking one inlet impulse line and (2) then opening the equalizing port which bypasses the blocked inlet to equalize the P cell at process pressure. Because it basically operates like a 3-way valve, this forced zeroing sequence provides fool-proof operation and safety. After correcting for zero offset, the transmitter is returned to service by simply redialing the handle to the NORMAL position which, again, correctly sequences back to the service mode by closing the equalizer first and then reopening the blocked inlet.
The first step in depressurizing a transmitter is to equalize the H.P. and L.P. sides to avoid possible damage to the transmitter. This is done by dialing the Zeroing Valve to the ZERO position. Next, the Blocking Valve can be dialed to the DEPRESS position which blocks off the process pressure allowing both cavities of the transmitter to be simultaneously depressurized thru the common vent valve.
By dialing the Zeroing Valve and Blocking Valve handles to the ZERO and BLOCKED positions respectively, the MM6UC is automatically switched to the islolation mode where both inlets are blocked and the equalizing port is closed. The transmitter is now safely isolated and prepared for field servicing, recalibration or removal. The transmitter is returned to service by simply redialing the handles to their NORMAL positions which, again, correctly sequences back to the service mode by leaving the equalizer blocked and reopening both inlets.
Testing for Equalizer Leakage
Equalizer leakage can be checked by leaving the Zeroing Valve in the NORMAL position and dialing the Blocking Valve to the BLOCKED position. In this mode, the equalizers on the 3-way Zeroing Valve and 3-way Blocking Valve are both closed. The cavity between these blocked equalizers can now be vented to check for leakage. If leakage is detected, slightly tighten the Zeroing Valve packing nut.
Note: Because of the unique fool-proof design, the Zeroing Valve and Blocking Valve handles can be dialed to their respective positions in any order without causing improper operation.
6000psi @ -150ºF to 150ºF
2500psi @ 220ºF
Flanged instrument x Flanged process
ANSI B31.1, B16.5, NACE MR-01-75(special order)
Barstock, A479 - 316, A276-316;
Cast, ASTM-A743 CF3M, ASTM-A-351 CF3M, A 276-316.
Materials of Construction:
Body: Investment cast 316SS or low grade (non-certified) SS
Wetted Plug: 316SS
Plug Liner: Teflon or Glass Filled Teflon
Face Seals: Ryton reinforced Teflon
Non-Wetted Trim: 303SS
Handle: Cast aluminum arrowhead - PVC coated
Plugs / Bleed Valve:303SS
Exotic materials: Hastelloy C, Monel, Alloy 20, etc. consult factory.
All units are supplied with 4 transmitter mounting bolts, 2 face seals and
Assurance of Satisfaction: When properly installed, D/A guarantees the MM6UC to be free from defective workmanship and material under normal use and service for a period of one year from date of shipment.