The African nation have won a medal in seven of the eight categories and boast four golds, with today's double added to those won by Yakubu Adesokan and Ivory Nwokorie.
Oyema was first up at the ExCeL in the women's -48kg and matched the world record set by compatriot Lucy Ejike with an opening lift of 130kg.
The 30-year-old broke that with her second attempt of 132kg and then extended it to 135kg, although she did miss out on a fourth attempt at 140kg.
'The people of Nigeria will feel so happy,' said Oyema, who finished ahead of Russian world champion Olesya Lafina and China's Shi Shanshan.
'For the Paralympians to bring medals back to our country, they will feel very happy.
'I'm not surprised because I worked very hard for it.
'I feel very, very good. I decided to be a world recorder and to be a champion. I never doubted it.
'There are more records to come. I will keep going, by the grace of God.'
Nigeria's Powerlifting dominance continued in the -52kg category as Tamara Podpalnaya of Russia and China's Xiao Cuijuan were beaten into second and third respectively.
Sapele-born Onaolapo dominated proceedings and after breaking the category's Paralympic record with a second lift of 130kg, she successfully completed 131kg to break the world record.
'We are doing well because we have determination, discipline and focus,' she said of Nigeria's success.
'We take it very seriously. It is our job. We don't get paid, but we treat it as our job and take it very seriously.'
That was shown once again in the last session of the day as Ifeanyi Nnajiofor took silver in the men's -60kg category with a lift of 188kg.
Nader Moradi ensured gold would go to Iran with a best of 196kg.