Materiales

Question 1

Maximum temperature listed is based on the ATEX standard for T4 temperature classification:

Answer 1

If you are operating in a non-explosive environment, FKM fluoroelastomer’s maximum fluid temperature in aluminum or stainless steel pumps is 320°F (160°C).
Actual pump performance may be affected by prolonged usage at temperature.

Question 2

Para fluidos de mayor viscosidad:

Answer 2

Utilizar bolas mas densas. Las bolas densas sellan mas rapido –menor pulsacion.

Experimento; bola en agua…
Santoprene; flota en el agua.
PTFE; se hunde en el agua.
Thicker fluid needs more dense balls to seat properly.
SST balls instead of Geolast.

Question 3

Para alcanzar un mayor grado de succion:

Answer 3

Utilizar Asientos y Bolas mas suaves – sellan mejor – fluidos densos. El caucho y los elastomeros son tipicamente usados.

Question 4

Configuración bola/asiento para fluidos abrasivos:

Answer 4

La experiencia convencional dice que hay que tener una combinacion de duro/suave de la bola con el asiento. Por ejemplo: Bola de Santopreno y asiento de SST o vice versa.

Question 5

Materiales resistentes a la abrasión:

Answer 5

Mejor: Acero Inox.
Excelente: Santopreno, acetal, Geolast (cuando hay compatibilidad quimica)
Moderado: polipropileno, Hytrel (TPE)
Malo: PTFE (Teflon) (posibilidad de derretimiento)

Question 6

Aluminum

Answer 6

Medium corrosion and abrasion resistance. Not for use with halogenated hydrocarbons.

Question 7

Stainless Steel

Answer 7

High level of corrosion and abrasion resistance. Passivated 316 grade.

Question 8

Hastelloy

Answer 8

Good in corrosive environments. Good resistance to aggressive chemicals and compatible with high-temperature fluids. C-22 grade.

Question 9

Polypropylene

Answer 9

Wide chemical compatibility. General purpose.

Question 10

Conductive Polypropylene

Answer 10

Wide range of solvent resistant and withstands extreme fatigue. Good level of abrasion resistance. Not for use with acids or bases.

Question 11

PVDF (Kynar)

Answer 11

Wide chemical compatibility. General purpose. ATEX approved. Strong chemical resistance: Acids and bases. Good abrasion resistance. High temperature resistance.
Requiere permisos especiales en casi todos los paises, excepto Argentina.

Question 12

Thermoplastic Polyester Elastomer (TPE, Hytrel, Saniflex)

Answer 12

Good low temp properties. Good abrasion resistance.

Not for chemicals, oil& gas OK.

Question 13

Santoprene (WilFlex)

Answer 13

Blend of EPDM and Polypropylene, It does not work well with petroleum based products.
Good abrasion and chemical resistance. OK for use with some solvents, (e.g. MEK, acetone) caustic solutions, dilute acids, and alcohols. Often substituted for EPDM or EPR.
Bueno con quimicos como sustituto de PTFE pero más económico y con mayorresistencia a la abrasión.

Question 14

Geolast

Answer 14

Blend of Buna and Polypropylene, and works well with petroleum based product.
Good abrasion resistance. Approximately same chemical
compatibility as Buna.
It doesn’t have fabric in the middle as Buna.

Question 15

Buna

Answer 15

Good for petroleum-based fluids, water, oils, hydrocarbons and MILD chemicals (e.g. mineral spirits). Not for sue with strong solvents or chemicals (e.g. acetone, MEK, ozone, chrlorinated hydrocarbons, and nitro hydrocarbons)

Question 16

FKM Fluoroelastomer (Viton)

Answer 16

High heat resistance. Good resistance to aggressive chemicals including acids and some solvents (e.g. Xylene
and mineral spirits). Good resistance to steam as well as
animal, vegetable and petroleum oils. Resists unleaded
fuels. Not for use with ketones, low molecular weight ester and nitro containing compounds. Max 121C o 250F

Question 17

PTFE

Answer 17

Widest chemical compatibility, extreme corrosion
resistance, very low frictional coefficient, non-adhesive,
high heat resistance. Poor abrasion resistance. Max 93C, 82.2C

Question 18

Polychloroprene or Polychloroprene Weighted

Neoprene

Answer 18

High resilience. Good with whiskey, wine, beer and natural gas. Good with animal and vegetable oil, moderate chemicals, fats and greases. Not for use with strong oxidizing acids, esters, ketones, chlorinated aromatic and nitro hydrocarbons.

Question 19

Acetal

Answer 19

Wide range of solvent resistant and withstands extreme
fatigue. Good level of abrasion resistance. Not for use
with acids or bases.

Question 20

EPDM, used with 3A
pump (Ethylene Propylene Diene M-class rubber)

Answer 20

High heat resistance. Good resistance to gas permeability and to steam. OK with caustic solutions, dilute acids, ketones and alcohols. Recommended for use with CIP Sanitizing Agent OXONIA.
Poor petroleum oil and solvent resistance. Not for use with aromatic hydrocarbons. Up to 135C or 275F