Russian Version | English Version

Main page Sitemap Feedback Search the site

EPS blocks and sheets manufacturing equipment

Clinker Panel

Insulated Concrete Forms (ICF) manufacturing equipment

Molded styrofoam

PV-1 and PV-3 preexpanders

/images/oborudovanie_pps/predvspenivatel.jpg Preexpander is designed for preexpansion of EPS beads by heat treatment. Saturated water steam is used as heat conductive medium.


There are two types of preexpanders:

  • continuous operation
  • batch operation

We manufacture BATCH OPERATION preexpanders (hereinafter referred to as Preex).

We opt to manufacture a Preex of this type as it has a number of advantages over the continuous operation variety.


Disadvantages of continuous operation preexpanders:

1) Bead density is adjustable by the following three methods, usually, in the following order:

  • steam supply adjustment
  • infeed rate adjustment
  • bypass height adjustment, if any

All the above three methods rely on adjustment of the time the beads are stored inside the chamber.

2) Steam pressure can only be reduced (by mixing it with air) but never increased, as the process runs at ambient pressure (continuous operation preexpanders are open and unsealed). This disadvantage leads not only to a risk of a possible process irregularity but also to increased steam flow and higher costs of steam generation.


3) Average time the material is inside the continuous operation preexpander is about 3 minutes, however, minimum target density of expanded beads is directly related to pentane content.


Advantages of batch operation preexpander:

1) The pressure is adjustable, as the result steam temperature can be selected so as to match the required EPS density or pentane content of the raw material. !!! If steam temperature is outside the required range, steam can damage the cells.

Conforming cell structure

Damaged cell structure

 /images/oborudovanie_pps/yacheyki_good.jpg

 /images/oborudovanie_pps/yacheyki_bed.jpg

The lower is pentane content, the later is the preexpansion and the higher is the temperature required.

2) Batch operation preexpander is a sealed receptacle that supports lower steam flow and higher preexpansion rate as compared to the continuous operation Preex.

Bead density is adjusted as follows during batch operation of the preexpander:

  • adjustment of steam treatment time;
  • adjustment of the raw material volume for each feed;
  • adjustment of the height of the preexpanded bead layer inside the operating chamber;
  • steam pressure adjustment;
  • steam volume adjustment.

As we can see from the above, batch operation preexpanders are more flexible and can support lower densities even for relatively small beads. Switching between volumes is quick and the loss is very small.

Standard preexpander types

preexpander EPS

PV-1
A preexpander with the capacity of 10 cub.m. per hour, suitable for the complete line with the capacity of 70 to 90 cub.m. per 8 hour shift depending on the skills of operators.

Raw material is fed manually through a funnel on top of the receptacle. Beads are discharged through a manually or pneumatically operated discharge door (customer selected option).

preexpander EPS

PV-1A (automatic)
High-capacity preexpander that could be integrated into the 200 cub.m./shift manufacturing line.

Remotely controlled, supports full automatic and manual modes. Raw material is fed using an additional loading screw-type hopper. Batching is by weight. Expanded beads are discharged to a dryer and then to silo hoppers. Expanded beads are transported by air transport with a Venturi tube to avoid deformation.

       ()

PV-3

 
A small-sized cost-effective batch operation preexpander, capacity: 0,75 cub.m./hour. Ideal for processes where expandable polystyrene is not a primary raw material, such as lost foam casting (LFC), EPS concrete manufacture, production of bean bags, stuffed toys with EPS-based filling; production of tourist and sports gear, etc.

Manual feed through a funnel, discharge through a door. Custom manual drive option is available upon request.

Preexpander specifications
(for 25 grade EPS)

Parameter

Value

PV-1 manual

 PV-1a automatic

PV-3
Rated capacity per cycle, cub.m

 1,0

 1,0

0,05
 Machine capacity, cub.m/hour, at least

 10

 15

0,75
Operating volume, cub.m

 1,2

 1,2

0,08
Bottom and stirrer material

stainless steel

EPS density grade

15, 25, 35, 50

Bulk weight of beads after preexpansion, kg/cub.m

 11...40

Operating steam pressure, MPa, max

 0,01...0,03

Activator rotation rate, rpm

 90

Operating steam temperature, °C

 100...108

Dimensions (receptacle diameter), mm

1100x1050x2800

 341010504370

10308201400
Weight, kg

 530

 750

180
Serviced by, operators

 1

Electric specifications

Supply current

alternating, three-phase

Rated current frequency, Hz

 50

Rated supply voltage, V

 380

Number of installed electric drives, pcs

 1

3 1
Rated drive power, kW

 4

 22

2

Watch the preexpander and dryer in action

Production

Production techniques

Production plant

Production area demands

Equipment

Preexpander

Silo bunkers

Blockmold

Vacuum system

EPS cutter

Prebreaker/grinder

Steam boiler

Steam accumulator

Production line variants

40 sq. m. output

55 sq. m. output

60 sq. m. output

Prices

All about EPS
Properties   
Description   
Structural application   
Molded EPS   
EPS furniture   
Russian State Standard (GOST)   
How to purchase?

Where you can see our equipment in action

Prices

How to purchase?

Contact

How to find us?

Address: Russia, Kirov, ul. Proizvodstvennaya, 21a
Telephone: +7 (8332) 522-661, 521-121, 252-861
Fax: +7 (8332) 511-445, 51-33-22
E-mail: info@v-s-d.ru

Find us on the map

Information of interest

video presentations

Frequently Asked Questions

© Vyatkastroydetal, 2007

Designed by Infinity, 2007