绝缘铜管母线绝缘层:difference是可数名词吗

可数，也可以不可数：
difference 表示"差异,差别",可数:
There are many differences between living in a city and living in the country.生活在城市和生活在乡村有许多不同之处.
difference 表示"差额,差数",不可数:
The difference between 5 and 11 is 6.十一和五的差是六.
Flowers make no/a lot of difference to a room. 一个房间里有没有鲜花没有/有很大差别.
It doesn't make much/any/the least difference to me what you do .你干什么对我都没有多大/任何/丝毫关系.
When you're learning to drive, having a good teacher makes all the difference.初学驾驶如有好的老师指导,差别很大.
difference 表示"不和,分歧",可数:
They've settled their differences and are friends again.他们已消除芥蒂,重归于好.

difference是可数名词。

例：differences in color and size;
颜色和尺寸间的差别；

a difference of opinion.
观点的差异。

difference 可用作可数名词亦可用作不可数名词，常与介词 between 连用，表两者间的不同。

典例 ：

It's hard to see many differences between the two parties.

很难看出两党之间有多少不同。（两党之间并没有很多差异。）

What is the difference between American food and Chinese food?

中国食物与美国食物有什么不同？

There is not much difference in price. 在价格上没有太大差异

通常是用为可数的,但有时也是不可数的
eg.1,There are many differences between living in a city and living in the country(不同之处，差异）
2, make all the difference (非常重要；作用很大）

是可数名词．

yes