Relays Series 63 Constant Differential Flow Controllers Introduction Features & Benefits Versatile and design accommodates liquids or gases and wide range of OEM needs Powder coating provides improved corrosion resistance Description The Series 63 Constant-Differential Relays are used in conjunction with an external needle valve to provide constant volume flow rates of liquids or gases over a continuously adjustable range. For gas flow applications, compressibility must be considered if a constant mass flow is desired. Therefore, models are available for constant upstream or downstream reference pressure. Supply Pressure For liquids, which are not compressible, the constant volume flow will also be a constant mass flow, regardless of Minimum: At least 5 psig greater than the maximum upstream or downstream pressures. As such, mass flow is downstream pressure of the needle valve-controller combination independent of pressure changes. Maximum: Needle Valve The relay’s needle valve determines rangeability and capacity. Model Open Four models are available. 63BD 250 psig 63BDL 250 psig 63SD 500 psig Specifications 63SDL 500 psig Range Limits Ambient Temperature Limits @20 psig supply o o Model 63BD & BDL: -40 to 180 F (-40 to 82 C) Model 63BU & Model 63SU o o Model 63SD & SDL: -40 to 250 F (-40 to 121 C) Maximum: 1.1 scfm Controlled Differential Minimum: 0.01 scfm 3.1 ±.5 psig (others optional) Model 63BUL & Model 63SUL Maximum: 2800 sccm Materials Minimum: 13 sccm Brass 316 SS Supply Pressure Units Units Minimum: At least 5 psi greater than the maximum Body Brass 316 SS downstream pressure of the needle valve-controller Diaphragm Neoprene KYNAR combination 7 Differential Spring 18-8 SS 316 SS Maximum: Needle Valve Valve Plunger & Seat 303 SS 316 SS Model Closed Open 63BU 100 psig 250 psig Plunger Spring 63BUL 50 psig 250 psig (used in “D” 63BD 316 SS 316 SS 63SU 50 psig 500 psig models only) 63BD-L Phos. Br. 316 SS 63SUL 250 psig 500 psig Ratings Ambient Temperature Limits Ambient Temperature o o Model 63BU & Model 63BUL: -40 to 180 F (-40 to 82 C) o o -40 to 180 F (-40 to 82 C) o o Model 63SU & Model 63SUL: -40 to 250 F (-40 to 121 C) 7.23 Relays Series 63 Constant Differential Flow Controllers Technical data Flow Capacity Formula Higher Range Low Flow Models 63BD and 63SD; Models 63BD-L and 63SD-L; 63BU and 63SU 63BU-L and 63SU-L GAS FLOW-CAPACITY � Maximum at less than SCCM = 4000 ΔP x Pd x 530 SCCM = 400 ΔP x Pd x 530 1 critical flow SG T � SG T 1 Maximum at critical flow SCCM = 2000 Pu 1 x 530 SCCM = 200 Pu 1 x 530 � SG T �SG T Minimum controllable flow Approximately 1/200 of maximum SCCM = 8 ΔP (Pu + Pd) Rv T LIQUID FLOW-CAPACITY Maximum CCM = 470� ΔP CCM = 47 ΔP SG � SG Minimum Approximately 1/200 of maximum CCM = .06 ΔP Rv NEEDLE VALVE SIZING (With 3 psi drop across valve) CCM For any liquid Kn = 6550 � 1 SG SCCM For any gas Kn = � 49000 1 x Pn x 530 SG T Mounting Dimensions Model DIM. A DIM. B 7 63BU 2 1/8” 3 1/4” 63BUL 2 1/8” 3 1/4” 63SU 2 3/8” 3 1/2” For gases with constant For gases with constant 63SUL 2 3/8” 3 1/2” downstream pressure upstream pressure 63BD 2 1/8” 3 1/2” 63BDL 2 1/8” 3 1/2” 63SD 2 3/8” 3 3/4” 63SDL 2 3/8” 3 3/4” Note: Dimensions for 63D are mirrored from 63U 1) Critical flow exists when the ratio of upstream pressure (Pu) to downstream pressure (Pd) is equal to or less than approximately 0.53 7.24