Application of Products

The use of metal bellows seal gate and globe valves has been successfully applied for over 30 years. Bellows seal valves reduce fugitive emissions of toxic, lethal, or regulated fluids/gases, minimize maintenance, reduce life cycle costs, and optimize productivity in process plants. This includes steam, cryogenic, and vacuum systems. The following is a list of the fluids and gases processed with metal bellows seal gate and globe valves:

ACETALDEHYDE                    ETHYLIDENE DICHLORIDE      2,2,4-TRIMETHYLPENTANE
ACETAMIDE                                 (1,1-DICHLOROETHANE)    VINYL ACETATE
ACETONITRILE                       FORMALDEHYDE                     VINYL BROMIDE
2-ACETYLAMINOFLORIDE     GLYCOL ETHERS                     VINYL CHLORIDE
ACROLEIN                               HEXACHLORONBENZENE       VINYLIDENE CHLORIDE
ACRYLIC ACID                        HEXACHLOROBUTADIENE         (1,1-DICHLOROETHYLENE)
ACRYLONITRILE                     HEXACHLOROETHANE           XYLENES (ISOMERS
ALLYL CHLORIDE                   HEXAMETHYLENE-1,                   AND MIXTURES)
4-AMINOBIPHENYL                 6-DIISOCYANATE                    O-XYLENES
ANILINE                                   HEXANE HYDRAZINE              P-XYLENES
O-ANISIDINE                            HYDROQUINONE                     ANTIMONY COMPOUNDS
BENZENE                                 ISOPHORONE                          ARSENIC COMPOUNDS
BENZIDENE                             MALEIC ANHYDRIDE                   (INORGANIC INCLUDING
BENZOTRICHLORIDE              METHANOL                                    ARSINE)
BENZYL CHLORIDE                 METHYL BROMIDE                  ASBESTOS
BIPHENYL                                        (BROMOMETHANE)         BERYLLIUM COMPOUNDS
BIS (2-ETHYLHEXL                  METHYL CHLORIDE                 CADMIUM COMPOUNDS
  PHTHALATE (DEHP))                  (CHLOROMETHANE)           CALCIUM CYANAMIDE
BIS (CHLOROMETHYL)            METHYL CHLOROFORM          CAPTAN
ETHER BROMOFORM                 (1,1-1-TRICHLOROETHANE) CARBARYL
1,3-BUTADIENE                        METHYL ETHYL KETONE       CHLORAMBEN
CAPROLACTAM CARBON           (2-BUTANONE)                     CHLORDANE
DISULFIDE CARBON                METHYL HYDRAZINE             CHLORINE
TETRACHLORIDE                     METHYL IODIDE                    CHLOROBENZILATE
CARBONYL SULFIDE                     (IODOMETHANE)               CHROMIUM COMPOUNDS
CATECHOL                              METHYL ISOBUTYL KETONE COBALT COMPOUNDS
2-CHLOROACETOPHENONE        (HEXONE)                             COKE OVEN EMISSIONS
CHLOROBENZENE                   METHYL ISOCYANATE            CYANIDE COMPOUNDS
CHLOROFORM                        METHYL METHACRYLATE       DICHLORVOS
CHLOROMETHYL METHYL    METHYL TERT BUTYL ETHER ETHYLEBE IMINE
  ETHER                                             (MTBE)                                   (AZIRIDINE)
CHLOROPRENE                        4,4'-METHYLENE BIS               ETHYLENE
CRESOLS/CRESYLIC ACID             (2-CHLOROANILINE)          HEPTACHLOR
  (ISOMERS AND MIXTRS)       METHYLENE CHLORIDE          HEXACHLOROCYCLO-
O-CRESOL                                       (DICHLOROMETHANE)           PENTADIENE
M-CRESOL                               METHYLENE DIPHENYL           HYDROCHLORIC ACID
P-CRESOL                                DIISOCYANATE (MDI)               HYDROGEN FLUORIDE
CUMENE                                  4,4-METNYLENEDIANILINE          (HYDROFLUORIC ACID)
2,4-D,SALTS AND ESTERS      NAPHTHALENE                         LEAD COMPOUNDS

DDE                                         NITROBENZENE                          LINDANE (ALL ISOMERS)
DIAZOMETHANE                     4-NITROBIPHENYL                      MANGANESE COMPOUNDS
DIBENZPFURANS                    4-NITROPHENOL                         MERCURY COMPOUNDS
1,2-DIBROMO-3                       2-NITROPROPANE                      METHOXYCHLOR
CHLORPROPANE                    N-NITROSO-N-METHYLUREA     FINE MINERAL FIBERS
DIBUTYLPHALATE                 N-NITROSOMETHYLAMINE        NICKEL COMPOUNDS
1,4-DICHLOROBENZENE(P)    N-NITROSOMORPHOLINE          PARATHION
3,3-DICHLOROBENZIDENE      PHENOL                                     PENTACHLORONITROBENZENE
DICHLORETHYL ETHER (BIS    P-PHENYLENEDIAMINE                 (QUINTOBENZENE)
  (2-CHLORETHYL) ETHER)       PHOSGENE                              PENTACHLOROPHENOL
1,3-DICHLOROPREPENE            PHTHALIC ANHYDRIDE          PHOSPHINE
N,N-DIETHYL ANILINE             POLYCHLORINATED                PHOSPHORUS
  (N,N-DIMETHYLANILINE)       BIPHENYLS (AROCLORS)         POLYCYCLIC ORGANIC MATTER
 DIETHYL SULFATE                1,3-PROPANE SULFONE            QUINOLINE
3,3'-DIMETHOXYBENZIDINE    BETA-PROPIOLACTONE            RADIONUCLIDES
DIMETHYL                               PROPIONALDEHYDE                      (INCLUDING RADON)
  AMINOAZOBENZENE              PROPOXUR (BAYGON)              TITANIUM TETRACHLORIDE
3,3'-DIMETHYLBENZIDINE        PROPYLENE DICHLORIDE        TOXAPHENE
DIMETHYL CARBAMOYL         (1-2-DICHLOROPROPANE)            (CHLORINATED CAMPHENE)
  CHLORIDE                              PROPYLENE OXIDE                  STEAM
DIETHYL FORMAMIDE             1,2-PROPYLENEIMINE              AMMONIA
1,1-DIMETHYILYDRAZINE            (2-METHYL AZIRIDINE)        OXYGEN
DIMETHYL PHTHALATE         QUINONE                                   HYDROGEN
DIMETHYL SULFATE              STYRENE                                  CARBON DIOXIDE
 4.6-DINITRO-O-CRESOL,         STYRENE OXIDE                       ARGON
  AND SALTS                           2,3,7,8-TETRACHLORO-             NITROGEN
2.4-DINTROPHENOL                 DIBENZO-P-DIOXIN                    HELIUM
1,4-DINTROTOLUENE               1,1,2,2,-TETRACHLORO-            SULFURIC ACID
1,4-DIOXANE (1,4-                            ETHANE                             HYDROGEN CYANIDE
  DIETHYLENEOXIDE)              TETRACHLOROETHYLENE        HYDROFLOURIC ACID
1,2-DIPHENYLHYDRAZINE             (PERCHLOROETHYLENE)     HYDROCHLORIC ACID
EPICHLOROHYDRIN (1-CHL.    TOLUENE                                   HYDROGEN BROMIDE
  -2,3-EPOXYPROPANE)            2,4-TOLUENE DIAMINE               PHOSGENE
1,2-EPOXYBUTANE                  2,4-TOLUENE DIISD­-                   POTASSIUM
ETHYL ACRYLATE                         CYANATE                           SODIUM
ETHYL BENEZENE                   O-TOLUIDINE                             CHLORINE
ETHYL CARBAMATE               1,24-TRI-                                    TRITIUM
  (URETHANE)                                  CHLOROBENZENE              URANIUM HEXAFLOURIDE
ETHYL CHLORIDE                    1,1,2-TRI-                                   SILANE
  (CHLOROETHANE)                          CHLOROETHANE               HOT OILS
ETHYL DIBROMIDE                  TRICHLOROETHANE                 SOUR GAS
  (DIBROMOETHANE)                TRIETHYLAMINE                      OIL
ETHYL DICHLORIDE                 TRICHLOROETHYLENE             FREON
  (1,2-DICHLOROETHANE)          2,4,5-TRICHLOROPHENOL         CAUSTIC SOLUTIONS
ETHYL GLYCOL                        2,4,6-TRICHLOROPHENOL         HOT GYCOLS
ETHYL OXIDE                           TRICHLOROETHYLENE             ETHYL MERCAPTAN
ETHYL THIOUREA                    TRIETHYLANINE                       SYNTHETIC HEAT
                                                 TRIFLURALIN                                 TRANSFER FLUIDS

Eagle America bellows seal valves have been designed to increase the durability of a packed stem seal valve with the addition of a reliable metal bellows to seal the moving stem. A standard packed valve has a compression packing sealing system on the stem along with a full open shut-off metal to metal back seat between the stem and body. The bellows seal is the primary stem seal of the bellows seal valve, but includes the packing and back seat in the design. Bellows cycle testing has been conducted at room temperature and elevated temperatures to the requirements of MSS SP-117 and API 602. Eagle America has selected a number of standard valve designs and material combinations to offer a competitive approach to sealing a majority of gate and globe valves.

Theory Behind Metal Bellows

Metal bellows are deep corrugated piping which are flexible and pressure resistant. Metal bellows may be manufactured with deep corrugations mechanically or hydraulically formed into a thin walled, welded tube (or multi-layered thin walled tubes) or by alternately welding the inside and outside diameters of thin, formed washers (single or multiple plys). The radial corrugations give the bellows flexibility to be attached (weld or static seal) and compress and/or extend to allow the ends to move relative to each other. The pressure resistance of the bellows is increased above that of an equivalent thin walled tube because of the corrugations. The bellows supports external pressures better because the pressure is acting on the inside corrugation (smaller diameter of the bellows) and the “column” is stabilized with the external pressure.

Welded metal bellows are designed to “nest” together and to be “rippled” in the axial direction, which combines to create a short height and low axial stiffness. The welds are susceptible to stress concentrations and “HAZ” (Heat Affected Zone) material strength reductions. These affects limit the use of welded metal bellows in extension. The manufacturing process is more expensive than formed metal bellows due to the material requirements to make the rippled washers and the welding time.

Formed metal bellows have the advantage of a naturally pressure supporting shape, a half taurus at the inside and outside corrugations. The flat shape of the span between the inner and outer corrugations makes the formed bellows have a higher spring rate than the welded bellows. The rounded shape of the corrugations limits the compressed height of each corrugation, but allows the bellows to have equivalent stroking capabilities in extension and compression. The formed metal bellows costs need to be considered along with the additional costs associated with the increased lengths of the body/bonnet and stem.

Bellows Seal Valves

In order to incorporate a metal bellows stem seal into a standard packed valve, the body/bonnet and stem must be redesigned with added length. Formed bellows typically provide a more economical valve, although some globe valve designs allow the addition of a welded bellows stem seal without additional height added to the body/bonnet/stem designs.

Eagle America incorporates formed bellows into all of our standard gate and globe valves, with the exception of the large diameter (>2”) globe valves.

Eagle America uses a variety of materials in welded bellows seal valves. The standard material is Inconel™ 625. This material provides excellent corrosion resistance in most applications along with exceptional strength and cycle life capabilities. Additonal materials include 321 Stainless Steel, Hastelloy™ C276, Inconel™ 718, and others. The bellows have been laboratory and field tested to provide an extended service life.

In order to monitor the bellows and packing performance, the valve may be manufactured with ports in the Bonnet in order to access the cavity between the bellows and the packing. The ports may be used for leak testing purposes, as well as leak detection monitoring in service. Valves that are not equipped with ports in the bonnet have the bellows leak tested at final assembly prior to compressing the packing.

Eagle America valves are designed for field replacement of bellows, discs/gates, packings, and gaskets during maintenance cycles, rather than replacing the entire valve.