It consists of working steel tube, hard polyurethane foam plastic heat preservation layer and high-density polythene outside-protective tube which is made of high-density polythene materials to prevent damage in the transportation and working process. The material of heat preservation layer is hard polyurethane foam with density 60kg/m³, and the foam completely fills the space between steel tube and outside-protective tube with a certain of viscosity, making the steel tube, outside tube and heat preservation layer into a firm unity. This product is widely used in city centralized heat supply and refrigerating project with outstanding energy saving and easy installation, so it creates good economic and social benefits.

Uses:
It is used in centralized heat supply pipeline, refrigerating pipeline and industrial pipeline, etc.


Product specifications:15-1020
Thickness:30-200


Technical index:
Density:40-70
Compressive resistance:3.5-4
Closed ratio:95
Water absorption ratio:0.2
Working temperature:-196+120

Specifications of direct-buried heat preservation tube

specs. project diameter(mm)	steel tube outside diameter x wall thickness(mm)	outer tube outside diameter x wall thickness(mm)	insulation layer thickness(mm)	length(m)	length of tube end (mm)
DN50	57x3.5	125x3.0/140x3.0	31/38	6--12	150-200
DN65	76x3.5	160x3.0	39	6--12	150-200
DN80	89x4.5	180x3.0	43	6--12	150-200
DN100	108x4.5	200x3.0	43	6--12	150-200
DN125	133x4.5	225x3.5	43	6--12	150-200
DN150	159x4.5	240x3.5/265x3.9	37/49	6--12	150-200
DN200	219x6.0	315x4.9/330x4.9	43/51	12	200
DN250	273x6.0	365x5.6/380x5.6	40/48	12	200
DN300	325x7.0	420x7.0/440x7.0	41/51	12	200
DN350	377x7.0	470x7.0/500x7.8	40/54	12	200
DN400	426x7.0	550x8.8	53	12	200
DN450	478x7.0	600x9.4	52	12	200
DN500	529x7.0	650x9.8	51	12	200
DN600	630x8.0	750x11.1/760x11.1	49/54	12	200
DN700	720x8.0	850x12	53	12	200
DN800	820x9.0	950x13	52	12	200
DN900	920x10	1054x14	53	12	200
DN1000	1020x10	1155x14.5	53	12	200
DN1200	1220x10	1380x15	65	12	200

We can also offer other sizes of protective tubes to meet the need of customers' requirements.

Technical Parameters

polythene bushing	unit	index	testing method	polyurethane	unit	index	testing method
tensile strength	Mpa	20	GB/T8804	density	Kg/m3	60	GB/T6343
breaking elongation rate	%	>350	GB/T8804	tensile strength	Kpa	200	GB/T8813
breaking elongation rate	Mpa	>20	GB/T8804	tensile strength	Kpa	200	GB/T8813
notch impact strength	T/mm	>10	ISO179-82	bonding strength	Kpa	200
vicat softening point	.	120	ISO306-74	thermal conductivity	W/m.k	0.033	IGB/T10297
brittle temperature	.	50	Astmd746-79	cold resistance	.	-50	Astmd477-76
electric breakdown strength 10%HCI NaOH NaCI	Kv/mm	>30you	GB1408-78 Astmd543-67	heat resistance water absorption	Kg/m2	<120 0.2	ISO2896-74