Spray polyurea elastomers for pipeline antisepsis

1. Plan
A. Material
polyurea: ILSAN Polyurethane (Shanghai) Co., Ltd., without impregnant
primer: ILSAN Polyurethane (Shanghai) Co., Ltd. one component, solidify in humidity
protective coating: ILSAN Polyurethane (Shanghai) Co., Ltd. with impregnant
B. design for coat
pipeline surface + primer + polyurea + (protective coating)
If there is higher requirements on the appearance of outside elastomer, another layer of protective coating should be added on it. If the elastomer is underfloor or not directly exposed outdoors, the protective coating is not needed.

2. pretreatment of steel tube surface

Before construction, completely clear the dust, oil stain and other foreign matters on the base level of pipeline. Then warm up the steel tube at a temperature of 40℃-60℃, then do pretreatment. The above sequence can not be changed, especially spraying sand. The pressure can compress the chipping into the clearance in the surface on steel tube. It is quite complex to clear the chippings, and may affect the adhesive strength of polyurea.
Pretreat the steel tube surface by spraying sand or shot blasting, and the quality should up to Sa21/2 class of GB/T 8923 in "the Class of rust and descaling of steel surface before application", the
depth of should reach 50μm-75μm.
Level the surface with grinding wheel.
After pretreatment, clear the surface of steel tube and prevent humidity, rustiness and secondary pollution. Clean the surface with impregnant, when it completely volatilizes, coat the primer or spray elastomers within 4h, after 4h or it rusts again, please pretreat another time.
If the condition allows，take away the impregnant with high pressure dry air.
3. spray polyurea
1) calculation of raw material dosage
2) equipment condition:
core: America GUSMER Company H-20/35 series, HV-20/35 series，FF-3500，FF-2500 etc.
ejection gun: GX-7 DI，GX-7 400，GX-8
mixing space: 453#
regulate the pressure and temperature that the provider recommended
3)Finished the preparation of raw materials and equipments and the installation, spray polyurea according to the technological process that the provider recommended.
Please contact ILSAN Polyurethane (Shanghai) Co., Ltd. to learn more detail technological process.
4. construction of protective coating
coat protective coating on the surface of polyurea elastomers in order to prevent yellow stain
5. quality guarantee
Perdon in charge of the project should carry out a progress report to guarantee that the project is in accordance with the requirements of provider.
The manufacturers promised that they will provide services of on-the-spot examination, technique support and guide for material usage, etc. if is necessary before the construction finished.
When the construction finished, examine the finished products and solve the problems left over. Manufacturers can ask the third party to finish the service. Then, tidy the scene.
After the beginning, spray small pieces of elastomers sample periodically, examine their capabilities, make a record and keep them until the finish of construction.