Calculator in php for 1c Bitrix Site Management (web programming)

It is necessary to develop and implement in CMS Bitrix Site Management (small business edition) Calculator for calculating the weight of the heating main of pipes in insulation in Eurofuru 20t. As a result, the mass in kg and volume in %. It is possible to send a reply to the mail, as well as calculate the calculation. Examples of such calculators I can provide, you can pull out of there. I can provide all the mathematical formulas.