Why plastic processors need plastic ERP software
Plastic processing looks straightforward on paper: granules go into a machine and parts come out. In practice, a moulding or extrusion unit juggles several polymers and grades, colour masterbatches, regrind from its own scrap, dozens of moulds with different cavity counts and cycle times, and machines that switch between jobs several times a week. Plastic ERP software keeps material, moulds and machines in one system so that the plant knows what it consumed, what it produced and what it lost on every shift.
Polymer prices move often, and part weights of a few grams decide whether a job makes money. When consumption is estimated from a monthly stock count, the losses from heavy parts, high runner weight, excess rejection or unrecorded regrind stay hidden. DotOne, which we configure for injection, blow and roto moulders and extrusion units, records these at the machine and turns them into usable cost and yield information.
Materials: polymers, masterbatch, additives and regrind
- Virgin polymers: PP, HDPE, LDPE, LLDPE, ABS, PC, nylon, PET, PVC resin and compounds, stocked in kilograms by grade, melt flow index and supplier lot.
- Masterbatches and additives: colour, UV, anti-static, filler and other masterbatches tracked by shade or type and dosing percentage.
- Regrind: in-house ground scrap by polymer and colour, stocked as a separate item with its own value, and issued back within the limits your quality rules allow.
- Inserts and bought-out components: metal inserts, caps, handles and labels used in assembly.
- Packing material: polybags, cartons, crates and pallets by product.
Because many polymers are hygroscopic, drying requirements can be recorded on the material and the job card, so operators know which materials need drying and for how long before processing. Material mixing ratios for virgin, regrind and masterbatch are defined per product and checked against actual issue.
Injection moulding: moulds, cavities and cycle time
In injection moulding, the mould is as important as the machine. Each mould is set up in the ERP with its cavity count, part weight, runner weight, standard cycle time, suitable machine tonnage range and whether it is company-owned or customer-owned.
Production entry by shot
Operators record shots or cycles, working cavities, good parts and rejected parts per shift. If a cavity is blocked, output is calculated on the working cavities, and the loss is visible rather than buried in a lower count.
Material balance
Material issued to the machine is balanced against good parts multiplied by part weight, runners, start-up lumps, purging and rejected parts. Runners and rejects that go to the grinder become regrind stock.
Mould history
Each mould accumulates its shot count. Preventive maintenance can be triggered after a defined number of shots, and repairs, polishing and modifications are logged against the mould.
Common rejection reasons such as short shot, flash, sink marks, warpage, silver streaks, burn marks, flow lines and dimensional variation are configured as codes, so reports show which mould, machine and material lot generate most rejects.
Blow moulding, roto moulding and extrusion
Blow moulding
Bottles, jars and jerry cans are produced from preforms or parisons. The ERP records preform or material consumption, neck and flash waste, output by cavity and leak or drop test results.
Roto moulding
Water tanks, drums and large containers are moulded from powdered polymer. Charge weight per product, oven cycle and cooling time are recorded, and products are stocked by capacity and colour.
Pipe and profile extrusion
Pipes are produced in metres by diameter and pressure class, with weight per metre as the key control. The ERP compares actual kilograms per metre with the standard, records start-up waste and cut pieces, and stocks pipes by length and bundle. Film and sheet lines are handled in kilograms and metres with thickness and width.
Production planning and mould changeovers
A moulding shop typically has more moulds than machines, so planning is about which mould runs on which machine and when. The ERP considers customer schedules, finished stock, mould availability, machine tonnage and colour sequence, and proposes a plan that the planner can adjust.
Mould changeovers and colour changes are expensive in time and purged material, so the plan groups jobs to reduce them where delivery dates allow. Machine utilisation, downtime by reason and output against capacity are tracked for each machine. For assembly products such as household items or plastic furniture, the plan also covers bought-out parts and the assembly line. The production planning module provides the scheduling views.
Quality checks and lot traceability
Moulded and extruded products are checked at several points: first-off approval after a mould or colour change, patrol inspection during the run, and final inspection before packing. The ERP lets inspectors record dimensions, weight, visual defects and functional tests such as leak, drop or pressure tests against the job card, and blocks a lot from dispatch until it is cleared.
Each production lot carries the polymer lot, masterbatch and regrind used, the mould, the machine and the shift. When an OEM customer reports a problem, the investigation can start from that record rather than from memory. It also shows whether a particular resin lot or a particular regrind ratio is behind a rise in defects. The quality management module holds these inspection plans and records.
Costing a plastic part
Part cost in plastics is built from material cost and machine cost. Material cost depends on part weight plus its share of runner and rejection, at the current polymer and masterbatch prices, with credit for regrind reused. Machine cost depends on cycle time, cavities and the machine hour rate covering power, labour, mould depreciation and overheads.
DotOne calculates standard cost from the mould master and actual cost from shift data. Because polymer prices change frequently, many processors agree price variation clauses with OEM customers. The ERP can show the effect of a polymer price change on part cost and support the price revision discussion with data. More on this is on our costing software page.
Customers, job work and dispatch
Plastic processors serve very different markets. Component moulders supply automotive, appliance and electrical OEMs against scheduled orders with strict quality requirements. Household product, pipe and water tank makers sell through distributors and dealers with price lists and schemes. Some units mould on a job work basis using the customer material and mould.
The ERP supports all three. Customer-owned moulds and material are tracked separately and reconciled, and only moulding charges are billed for job work. For OEM supplies, part-wise inspection records and lot numbers are retained. Dispatch generates the GST e-invoice and e-way bill, and dealer orders can be booked on the mobile ERP app.
What is the best ERP for the plastic industry?
Look for plastic ERP software that understands moulds and material balance, not just finished goods. In a demo, ask the vendor to set up one of your moulds with cavities, part and runner weight, record a shift with a blocked cavity and rejections, send runners to regrind and show the cost per part. For extrusion, ask to see weight per metre control. If you work with OEM customers, check how inspection and lot traceability are recorded. Our page on plant maintenance software also explains how mould and machine maintenance are scheduled.
