PROCESS CONTROL VALVES
MODEL 988/989 Models 988 and 989 are globe-style control valves with pneumatic spring-return actuator. Originally designed for chemical plants and corrosive service, they have large diameter stems, special finishes on the stem and packing boxes, close-coupled guiding, and live-loaded packing systems. Rugged construction, longevity, and low maintenance make these valves a popular choice in industrial process applications. The main difference between the 988 and 989 are in the face-to-face dimensions.
Body sizes:
End connections:
Temperature range: -20° F to +750° F (-28 °C to +398 °C) Pressure drop:
3/4” (988 only), 1”, 1-1/2”, 2”
988 – NPT, SW, separable flanges for Classes 150#, 300#, and PN40 989 – separable flanges for Classes 150# and 300#, flanges in ASME or DIN
Maximum Cv:
From 0.25 to 50
TFE seat – up to 1480 psid, (102 bard) Metal seat – 740 psid, (51 bard)
Materials:
Body – CS, 316L SST, Ni-Mo-Cr, CW-12MW (988 only) Trim – 316L SST, HC-22
Face-to-face:
The Models 988 and 989 are versatile, heavy- duty throttling
988 – ISA - 75.08.07 (long) 989 – ISA - 75.08.01 (short)
valves for general or corrosive chemical service.
MODEL 988-MB Model 988-MB is a modified version of our Model 988 designed to handle hazardous fluids. To minimize fugitive emissions, it is fitted with a metallic bellows stem seal subassembly and live-loaded secondary stem packing seal. Inlet pressure is from full vacuum to 200 psig. This model protects against fugitive emissions.
Body sizes:
Temperature range: -20° F to +450° F (-28 °C to + 232 °C) Pressure drop: 200 psid, (13.8 bard) Seat leakage: Class IV and Class VI Options: High temperature service, NACE service,
3/4", 1”, 1-1/2”, 2”
Maximum Cv:
The Model 988-MB is a heavy duty control valve with maximum protection against leakage.
From 0.25 to 50
Materials:
Body – CS, 316L SST, Ni-Mo-Cr, CW-12MW (988 only) Trim – 316L SST, HC-22
End connections:
NPT, SW, separable flanges for Classes 150#, 300#, and PN40, flanges in ASME or DIN
multiple packing variations, stellited seat surfaces
Face-to-face:
ISA - 75.08.07 (long)
4
8
Powered by FlippingBook