Property Description
1.The surface of resin-rich layer should be smooth and clean, without damage, whitening, delaminating, foreign inclusion and exposed fiber. The convex-concave larger than 3mm in diameter and 0.5mm in depth (height) is not allowed; For the pssure vessel, the max. Allowable air bubble is 4mm in diameter. Within the area of 1m2, the air bubble within DN 4mm should be no more than 3, otherwise the repair should be given; the depth of crack should be no more than 0.2mm.
2.The outer surface should be smooth and even color without whitening. Fiberglass must be impgnated with resin. Foreign inclusion, exposed fiber, interlayer delaminating, delaminating and resin blister, etc. are prohibited.
3.For the resin content, it should be more than 90% in resin-rich layer, more than 75±5% in middle layer, more than 35±5% in structural layer and more than 90% in outer layer.
4.The taper angle at the inner wall of tank is no more than 1°.
5.Under the loading condition, the allowable hoop strain should not exceed 0.1%.
6.When the winding layers are wound at helical winding angel 80°, its tensile strength should be equal to or more than 15MPa.
7.Barceló hardness on product's surface should be no less than 40.
8.Water absorption should be no more than 0.3%.
9.Length tolerance (distance between the peaks of two ends) is 1%.
10. The tolerances of tower's straightness and installation verticality are both 1/1000mm towers' height.
11. The difference between the max. Diameter and min. diameter from the same section of the shell should not exceed 0.5% of shell ID.
12.Verticality between flange surface and stub should be conformed to the following table:

Nominal DN of flange stub	≤100	<250	<500	<1000	<1800	<2500	<3500	<4000
Verticality	1.5	2.5	3.5	4.5	6	8	10	13

13.Angle deviation of flange stub should be conformed to the following table:

Nominal DN of flange stub	<250	≥250
Allowable angle tolerance	1°	0.5°

Shijiazhuang JHR Import & Export Co., Ltd. is a leading manufacturer of FRP relative products. Now we mainly focus on researching and developing FRP products production lines. At present, we can supply advanced FRP pipe and tank production line, pultrusion production line, and membrane housing production lines. We not only supply these equipment, but also supply processing technical support. Our 3-axis all-in-one filament winding machine is very popular in the world.

We are also in charge of installation, engineering and maintenance service. With so many years of technological know-how, we are in capacity of manufacturing according to special design request, and aiming to supply high-quality and good performance FRP products, such as pressure vessel, pipe, cooling tower, ventilation fan, profile, grating and so on.

Our factory has obtained ISO9001: 2000 Quality System Certification, British Royal UKAS Certificate, ISO14001 Certification, ISO1800 Certification and National Grade II Installation Certification of Anti-corrosion. Because of the request of domestic and international markets, we constantly challenge with new technological development and provide high quality and reliable products and service.