Mining cable sheathing compound
This series of product is produced according to requirements of national standard GB7594.7-87 and complies with the provisions of the coal industry standard MT818-2009. 
Indicator requirements and measured performance

No.	Test item		Unit	Requirements	Results
Before aging	Tensile strength		Mpa	≥11.0	12.9
	Elongation at break		％	≥250	460
Air oven aging test	Ageing condition	Temperature	ºC	75±2	75±2
		Time	h	10×24	10×24
	Tensile strength after aging	/	Mpa	/	13.1
		Change rate	％	≤-15	2
	Elongation at break after aging	/	％	≥200	421
		Change rate	％	≤-25	-8
Thermal extension test	Test conditions	Air temperature	ºC	200±3	200±3
		Load time	min	15	15
		Mechanical stress	N/cm2	20	20
	Elongation under load		％	≤175	38
	Permanent deformation after cooling		％	≤25	7
Oil immersion test	Test conditions	Oil temperature	ºC	100±2	100±2
		Oil immersion time	h	24	24
	Tensile strength change rate		％	≤-40	-8
	Change rate of elongation at break		％	≤-40	-3
Tear test	Tearing strength		N/mm	≥5.0	8.5