Pingxiang Daier Separation Tech Aug 26, 2026

How Should Random Packing Supplier Quotations Be Compared Beyond Unit Price?

Introduction

Random packing quotations should not be compared only by price per cubic meter, kilogram or piece. Two suppliers may both quote “25 mm SS316L Pall Rings” while supplying products with different geometry, wall thickness, bulk density, material documentation, hydraulic data, packaging, quantity basis and commercial scope.

This is one reason tower-packing quotations can appear surprisingly different.

A buyer may receive:

Supplier A: USD/m³;
Supplier B: USD/kg;
Supplier C: USD/piece;
Supplier D: a lower EXW price but much larger freight volume;
Supplier E: a higher unit price but clearer technical data and material traceability.

If these offers are compared only by the headline unit price, the purchasing decision may be misleading.

The correct question is:

Are the suppliers actually quoting technically equivalent packing under the same commercial and quantity basis?

A useful quotation comparison should normalize:

Packing Geometry + Material + Size + Wall Thickness + Bulk Density + Hydraulic Basis + Quantity + Documentation + Packaging + Incoterm + Freight + Lead Time

before comparing final price.

1. Start by Confirming That Every Supplier Is Quoting the Same Packing Type

The first comparison point is product identity.

Verify whether every quotation actually refers to:

Pall Ring;
Raschig Ring;
Cascade Mini Ring;
Intalox Saddle;
another random packing geometry.

Two products may both be described broadly as:

“Metal tower packing”

while having very different:

open area;
surface area;
pressure drop;
bulk density.

Do not compare them as equivalent simply because both can be installed in a packed tower.

2. Confirm the Nominal Packing Size

Compare the same nominal size.

Examples:

16 mm;
25 mm;
38 mm;
50 mm;
76 mm.

Packing size affects:

specific surface area;
pressure drop;
capacity;
fouling tolerance;
piece count per unit volume.

A lower quotation for 50 mm packing should not be compared directly with a 25 mm packing quotation unless the engineering design allows both options.

3. Same Size Does Not Always Mean Same Geometry

Two suppliers may both quote:

25 mm Pall Ring

but the actual geometry may differ in:

height-to-diameter ratio;
opening shape;
number of tabs;
wall pattern;
material thickness.

These differences can affect:

bulk density;
surface area;
pressure drop.

Therefore:

Product name + nominal size is not always enough to prove technical equivalence.

Request a datasheet or drawing when comparison matters.

4. Material Grade Must Be Compared on the Same Basis

For metal packing, confirm the actual alloy.

Examples include:

carbon steel;
SS304;
SS316;
SS316L;
duplex or specialty alloys.

A quotation for SS304 cannot be compared directly with SS316L only by price.

Likewise, plastic packing may be quoted in:

PP;
PE;
PVDF.

Ceramic products may also have different compositions and physical properties.

Material is part of the technical specification, not simply a commercial label.

5. Do Not Use Generic “Stainless Steel” as an Acceptance Basis

A quotation that only states:

Stainless Steel Pall Ring

is incomplete if the project requires a specific alloy.

Ask the supplier to identify:

exact material grade;
applicable certificate or material information.

For corrosion-sensitive service, alloy identity may significantly affect service life.

6. Compare Wall Thickness for Metal Random Packing

Metal packing wall thickness can significantly influence quotation price.

A supplier using:

thinner sheet

may quote a lower price than one using:

heavier gauge material.

This does not automatically mean one is good and the other bad.

The correct question is:

Does the quoted wall thickness match the approved packing specification and provide the required mechanical integrity?

Compare on an equal basis.

7. Thicker Is Not Automatically Better

More metal increases:

weight;
material cost;
bed load.

Excessive thickness does not necessarily improve:

mass-transfer efficiency;
hydraulic capacity.

The target should be:

Correct geometry and mechanical integrity at the specified thickness

—not the heaviest available packing.

8. Compare Bulk Density

Bulk density is often one reason quotations differ.

It indicates approximate packing mass per unit bulk volume.

For example:

Bulk Density = kg/m³

A heavier packing design may require more raw material per cubic meter.

This may increase:

product price;
freight weight;
support-grid load.

But higher bulk density does not automatically mean higher performance.

9. Why Bulk Density Matters When Comparing USD/kg Quotations

Suppose:

Supplier A

USD 5.00/kgBulk density = 150 kg/m³

Approximate packing value:

5.00 × 150 = USD 750/m³

Supplier B

USD 5.80/kgBulk density = 110 kg/m³

Approximate packing value:

5.80 × 110 = USD 638/m³

Supplier B appears more expensive per kilogram but may actually be less expensive per packed cubic meter.

Therefore:

USD/kg comparisons can be misleading without bulk density.

10. Why USD/m³ Can Also Be Misleading

Price per cubic meter is often convenient because packed-bed quantity is volumetric.

But the comparison still requires technical equivalence.

Supplier A may quote a lower USD/m³ because the packing has:

thinner walls;
different geometry;
different material;
lower documentation scope.

Normalize technical specifications first.

11. Be Careful with USD/Piece Quotations

Piece pricing is common for some packing products and small quantities.

But pieces per cubic meter can vary significantly with:

packing size;
geometry;
manufacturing design.

To compare piece pricing, obtain:

approximate pieces/m³;
bulk density if relevant.

Then convert all offers to the same basis.

12. Choose One Normalized Commercial Basis

A good comparison sheet should convert all quotations to one basis such as:

USD/m³;
total packed-bed cost;
total delivered project cost.

For engineering procurement, total project cost is often more useful than unit cost alone.

13. Compare Specific Surface Area Where Relevant

Specific surface area is commonly expressed as:

m²/m³

It represents the geometric surface area available per unit packed volume.

Higher surface area may support greater mass-transfer opportunity.

But it should not be considered alone.

Higher area may also accompany:

smaller passages;
higher pressure drop;
increased fouling sensitivity.

Compare it together with hydraulic characteristics.

14. Compare Void Fraction

Void fraction indicates how much of the packed bed is open space.

Higher void fraction can support:

gas passage;
liquid drainage;
lower hydraulic resistance.

But void fraction alone does not define mass-transfer performance.

A technically meaningful comparison should examine:

Void Fraction + Surface Area + Geometry + Hydraulic Data

together.

15. Compare Packing Factor Carefully

Packing factor may be used in preliminary hydraulic calculations.

However, suppliers may report packing characteristics using:

different methods;
different definitions;
different test bases.

Do not assume two values from different datasheets are automatically directly comparable unless the calculation/test basis is understood.

16. Ask Whether Hydraulic Data Are Available

Useful engineering information may include:

pressure-drop data;
flooding/capacity correlations;
packing factor;
application references.

A supplier that provides only:

size + material + price

may still supply acceptable packing.

But for engineering-sensitive applications, stronger technical data make evaluation easier.

17. Be Careful with Unexplained Performance Claims

Statements such as:

“30% higher efficiency”;
“50% lower pressure drop”;
“best packing in the market”

are not sufficient without context.

Ask:

compared with what packing?
at what gas/liquid load?
under what test conditions?

Technical comparison should favor measurable information over marketing language.

18. Compare the Quantity Calculation

One supplier may quote:

exactly the requested packed volume;

while another includes:

installation allowance;
spare quantity;
additional volume.

Therefore, compare the actual quantity offered.

For example:

Supplier A

20.0 m³

Supplier B

21.0 m³ including 5% spare

Their total quotation cannot be compared fairly without normalizing quantity.

19. Packed Volume Should Match the Engineering Requirement

The basic packed volume is generally:

Tower Cross-Sectional Area × Packed Height

For multiple beds, calculate each bed separately.

Do not accept a supplier quantity blindly simply because it appears on the quotation.

Verify:

tower ID;
packed height;
total volume.

20. Check Whether Spare Packing Is Included

Some projects want additional packing for:

commissioning;
future replacement;
damaged pieces.

Others do not.

The quotation should clearly identify:

operating quantity;
spare quantity.

This avoids comparing one supplier's exact quantity with another supplier's quotation including spares.

21. Compare Material Documentation

Depending on the project, required documents may include:

Certificate of Conformity;
material certificate;
chemical analysis;
dimensional inspection report;
COA;
test report.

Do not compare suppliers based on the number of certificates alone.

Compare whether they can provide the documents actually required by the project.

22. Material Traceability Can Matter

For critical metal applications, buyers may want traceability between:

raw material;
production batch;
finished packing.

This can be important when:

alloy identity matters;
EPC QA plans require documentation.

For less critical applications, extensive traceability may not justify extra cost.

Use a risk-based approach.

23. PMI Requirements Should Be Defined Clearly

If Positive Material Identification is required, clarify:

who performs it;
which samples are tested;
whether third-party witnessing is required;
whether the cost is included.

A quotation without PMI should not be compared directly with another quotation that includes full PMI and inspection.

24. Compare Plastic Material Documentation

For plastic packing, ask whether the supplier can identify:

polymer type;
material grade where required;
relevant chemical compatibility information.

Do not rely only on:

“PP is acid resistant.”

Suitability depends on:

chemical species;
concentration;
temperature;
oxidizers;
solvents.

25. Compare Ceramic Packing Test Requirements

Depending on the application, ceramic quotation review may include properties such as:

acid resistance;
water absorption;
composition;
mechanical characteristics.

The required parameters should follow the project specification.

Do not require unrelated tests merely because another supplier's brochure lists them.

26. Compare Packaging Method

Random packing freight cost can be strongly affected by packaging.

Possible packaging includes:

cartons;
woven bags;
pallets;
wooden crates.

Different packing methods affect:

shipment volume;
protection;
handling;
breakage risk.

This is particularly important for ceramic packing.

27. Net Weight and Gross Weight Both Matter

A quotation should distinguish where possible between:

product net weight;
shipping gross weight.

Freight is frequently calculated using gross shipping data.

For large projects, packaging weight can become significant.

28. Ask for Estimated Packing Dimensions

Before comparing delivered cost, obtain estimated:

package quantity;
package dimensions;
total volume;
gross weight.

This allows freight evaluation.

A lower EXW packing price may become more expensive after transportation.

29. Freight Can Change the Supplier Ranking

Imagine:

Supplier A

Packing price: USD 20,000Freight: USD 10,000

Total: USD 30,000

Supplier B

Packing price: USD 22,000Freight: USD 6,000

Total: USD 28,000

Supplier A has the lower product price but the higher delivered cost.

For low-density plastic random packing, freight volume can be especially important.

30. Plastic Random Packing Is Often Freight-Volume Sensitive

Plastic packing may be:

lightweight;
bulky.

Therefore, the shipment can reach volumetric capacity before reaching heavy weight.

When comparing suppliers, consider:

Packing Price + Packaging Efficiency + Shipment Volume

not just USD/kg.

31. Metal Packing Is More Weight Sensitive

Metal packing typically has higher density.

Freight economics may depend more strongly on:

gross weight;
pallet/crate weight;
shipping mode.

For air freight, weight becomes particularly important.

32. Ceramic Packing Requires Both Weight and Breakage Consideration

Ceramic packing is relatively heavy and brittle.

A supplier may reduce freight volume using tighter packaging, but packaging must still protect the product.

An overly aggressive packaging method that produces excessive breakage is not a real cost saving.

33. Compare Incoterms Correctly

A quotation under:

EXW;
FOB;
CIF;
DAP;
DDP

does not include the same cost scope.

Therefore, do not compare:

USD 10,000 EXW

with:

USD 12,000 CIF

as though the second supplier is simply more expensive.

Normalize commercial scope first.

34. EXW Price

EXW generally leaves more transport responsibility and cost with the buyer.

The buyer may need to arrange:

pickup;
export logistics;
freight;
destination handling

depending on the actual transaction structure.

Use it when comparing factory-level pricing.

35. FOB Price

FOB includes a different cost boundary than EXW and applies to sea shipment under the relevant Incoterms framework.

When comparing FOB offers, confirm:

named port;
included export charges;
packaging.

36. CIF Is Not the Same as Delivered-to-Site Cost

CIF typically covers cost, insurance and freight to the named destination port under the applicable Incoterms definition.

It does not automatically mean:

all destination charges, duties and delivery to the plant are included.

Clarify the scope.

37. DDP or DAP Can Simplify Comparison—but Scope Still Matters

Delivered quotations can be convenient.

But confirm:

final delivery address;
import duties/taxes;
unloading;
customs clearance;
remote-area charges.

The quotation should clearly define what is and is not included.

38. Compare Lead Time

Tower packing may be needed during:

scheduled shutdown;
emergency replacement;
new-project construction.

A lower-priced supplier with an unacceptable lead time may create a much larger plant cost.

Compare:

production lead time;
documentation lead time;
freight time.

39. Emergency Replacement Changes the Buying Decision

During an unplanned shutdown, the dominant question may become:

Who can supply technically acceptable packing quickly enough to restart the tower?

In that case:

availability;
material stock;
manufacturing speed;
logistics capability

may outweigh small unit-price differences.

40. Compare Supplier Ability to Confirm Engineering Inputs

A competent quotation should preferably confirm basic project information such as:

tower diameter;
packing size;
packing material;
packed height;
quantity.

For more complex projects, suppliers may also need to understand:

operating service;
support-grid compatibility;
distributor arrangement;
replacement constraints.

This reduces the risk of supplying technically correct packing for the wrong tower configuration.

41. Supplier Responsiveness Has Engineering Value

If a supplier responds clearly to questions about:

dimensions;
material;
certificates;
packaging;
shipping weight;

the procurement process becomes easier.

Slow or unclear technical communication can create delays later during:

approval;
production;
inspection;
shipment.

The cheapest quotation can become expensive if every technical clarification takes a week.

42. Compare Drawing and Datasheet Quality

Useful supplier documentation should make it possible to understand:

product geometry;
dimensions;
material;
basic physical properties.

For custom or project-specific internals, drawing quality becomes even more important.

The purpose is not beautiful documentation.

It is preventing misunderstanding.

43. Compare Batch Consistency for Large Orders

A large tower may require many cubic meters of packing.

Production may involve multiple batches.

Ask how the supplier manages:

dimensions;
raw materials;
batch traceability;
inspection.

Consistency matters because the tower should not contain several substantially different packing geometries sold under one product name.

44. Compare Quality-Control Scope

Depending on the product, relevant checks may include:

dimensions;
material verification;
wall thickness;
visual condition;
quantity;
packing condition.

Ask what is routinely checked and what requires special customer specification.

45. Do Not Automatically Prefer the Supplier with the Most Documents

More paperwork can increase cost without improving the actual packing.

For a small standard PP Pall Ring order, a full third-party inspection program may be unnecessary.

For a critical alloy packing project, stronger QA may be justified.

The correct level depends on project risk.

46. Compare Technical Deviations Explicitly

A supplier may propose a deviation such as:

different wall thickness;
different packing size;
alternative alloy;
alternative geometry.

Do not allow these differences to remain hidden inside the quotation.

Create a:

Technical Deviation List

and evaluate each item.

47. An Alternative Is Not Automatically a Bad Offer

Sometimes a supplier may suggest an alternative because:

original material is difficult to source;
another packing provides lower pressure drop;
requested size is unsuitable for the tower diameter.

The buyer should evaluate the engineering basis.

The correct response is not automatically:

“No deviation allowed.”

It is:

Does the alternative satisfy the actual process requirement?

48. Compare Replacement Availability

For long-term plant operation, consider whether replacement packing can be supplied later.

Useful questions include:

Is the design standard?
Is the tool/mold still available?
Can partial replacement quantities be produced?
Is the product custom?

This matters for maintenance planning.

49. Compare Supplier Experience with the Actual Service

Experience may be useful when the project involves:

highly corrosive service;
fouling;
vacuum distillation;
gas scrubbing;
specialty absorbers.

But experience claims should not replace actual engineering checks.

A long customer list cannot make an incompatible material suitable.

50. Why the Lowest Unit Price Can Become the Highest Total Cost

A low-cost quotation can become expensive if it leads to:

excess freight;
wrong packing size;
insufficient quantity;
material mismatch;
poor documentation;
delayed shutdown;
rejection at incoming inspection.

Therefore, evaluate:

Total Technical and Commercial Risk

not only unit price.

51. Create a Technical Comparison Table Before the Price Comparison

A useful procurement approach is to compare technical parameters first.

Example:

Parameter

Supplier A

Supplier B

Supplier C

Packing Type

Pall Ring

Size

25 mm

Material

SS316L

SS304

Wall Thickness

Specified

Different

Bulk Density

Available

Surface Area

Available

Not stated

Certificates

Included

Partial

Quantity Basis

m³

Only after technical differences are understood should price ranking begin.

52. Then Normalize the Commercial Comparison

A second table may include:

Commercial Item

Supplier A

Supplier B

Supplier C

Normalized Packing Cost

USD/m³

Total Packing Quantity

—

Packaging

—

Freight

—

Incoterm

—

Lead Time

—

Total Delivered Cost

—

This separates:

Technical Equivalence

from:

Commercial Competitiveness

53. Common Mistake 1: Comparing Only USD/kg

A heavier packing may appear cheaper per kilogram but cost more per cubic meter.

Correct approach:

normalize by the actual packed-bed quantity.

54. Common Mistake 2: Assuming the Heaviest Packing Is the Best

Higher bulk density can mean more raw material.

It does not automatically mean better hydraulic or mass-transfer performance.

55. Common Mistake 3: Comparing Different Incoterms

EXW, FOB and delivered quotations include different cost scopes.

Normalize before comparison.

56. Common Mistake 4: Ignoring Wall Thickness

Two metal Pall Ring quotations may differ substantially in raw material consumption because of wall thickness.

Compare the specified design.

57. Common Mistake 5: Ignoring Freight Volume

Especially for plastic packing, low product price can be offset by high shipping volume.

58. Common Mistake 6: Comparing Certificates Instead of Requirements

One supplier may provide ten documents while another provides four.

The relevant question is:

Which required technical and QA documents are actually covered?

59. Common Mistake 7: Ignoring Supplier Quantity Assumptions

A quotation may use the wrong:

tower diameter;
packed height;
quantity basis.

Always verify the calculated volume.

60. Common Mistake 8: Selecting Price Before Resolving Technical Deviations

Once the lowest supplier has been selected internally, teams may become reluctant to reconsider technical differences.

Resolve major deviations first.

61. Data Needed to Compare Random Packing Quotations

Tower Information

tower internal diameter;
packed height;
number of beds.

Packing Requirement

packing type;
nominal size;
material;
quantity.

Metal Packing Requirements

wall thickness;
alloy grade;
certificate requirements.

Hydraulic Requirements

pressure-drop/capacity data if required;
surface area;
void fraction;
packing factor where applicable.

QA Requirements

COA;
material certificate;
inspection;
PMI if required.

Commercial Requirements

Incoterm;
destination;
delivery date;
packing method;
freight scope.

62. Random Packing Quotation Comparison Workflow

Step 1 — Freeze the Technical Requirement

Confirm:

type;
size;
material;
quantity;
required documentation.

Step 2 — Identify Every Technical Deviation

Do not compare non-equivalent offers as equivalent.

Step 3 — Normalize Quantity

Convert quotations to:

required m³;
total bed quantity.

Step 4 — Normalize Unit Price

Where useful, convert:

USD/kg;
USD/piece

into a common basis such as:

USD/m³

Step 5 — Compare Physical and Hydraulic Data

Review:

bulk density;
surface area;
void fraction;
packing factor;
hydraulic information.

Step 6 — Compare QA Scope

Confirm required:

material certificates;
inspection reports;
test data.

Step 7 — Compare Packaging and Freight

Obtain:

gross weight;
dimensions;
total shipment volume.

Step 8 — Normalize Incoterms

Compare offers at the same delivery boundary.

Step 9 — Compare Lead Time and Supply Risk

Check whether delivery matches the project schedule.

Step 10 — Evaluate Supplier Technical Responsiveness

Review:

clarity;
documentation;
response to deviations.

Step 11 — Calculate Total Delivered Project Cost

Not only unit packing price.

Step 12 — Select the Best Technically Acceptable Offer

The goal is:

Lowest appropriate total cost—not simply lowest unit price.

Frequently Asked Questions

Why do two suppliers quote very different prices for the same Pall Ring?

Possible reasons include differences in:

material;
wall thickness;
geometry;
bulk density;
documentation;
packaging;
commercial scope.

First confirm that the products are technically equivalent.

Should random packing be compared by kilogram or cubic meter?

Packed-bed requirements are normally related to volume, so comparing total required packed volume is often useful. If quotations are in kilograms, bulk density can help convert them to a common basis.

Is heavier random packing better?

Not automatically.

Higher bulk density may increase mechanical weight and cost without guaranteeing better mass-transfer or hydraulic performance.

Is thicker metal Pall Ring always better?

No.

Wall thickness should meet the approved design requirement. Excessive thickness is not automatically an engineering benefit.

What technical data should I request from a random packing supplier?

Depending on the project:

packing geometry;
nominal size;
material;
bulk density;
surface area;
void fraction;
packing factor;
hydraulic data;
wall thickness for metal packing.

Why should packaging be included in quotation comparison?

Packaging affects:

freight volume;
gross weight;
breakage protection;
handling.

It can significantly change total delivered cost.

Should the lowest EXW quotation win?

Not necessarily.

Compare:

technical equivalence;
freight;
documents;
lead time;
quality risk;
total delivered cost.

Can two 25 mm SS316L Pall Rings have different technical performance?

Yes.

Differences in geometry, wall thickness and manufacturing design can affect physical and hydraulic properties even when nominal size and alloy are the same.

What is the best way to compare three tower-packing suppliers?

Use two stages:

Technical comparison
Normalized commercial comparison

Eliminate unacceptable technical deviations before ranking price.

Engineering Takeaway

Random packing quotations should be compared only after the offers have been normalized to the same technical, quantity and commercial basis.

A strong comparison sequence is:

Confirm Packing Type → Confirm Size → Confirm Material → Compare Geometry/Wall Thickness → Normalize Quantity → Compare Hydraulic Data → Review QA Scope → Compare Packaging/Freight → Normalize Incoterms → Evaluate Lead Time → Compare Total Delivered Cost

The key purchasing question is not:

“Who quoted the lowest USD/kg or USD/m³?”

It is:

“Which supplier is offering the required packed-bed performance and material specification at the lowest acceptable total project cost and risk?”

That distinction prevents false savings caused by:

non-equivalent packing;
incorrect quantity;
freight differences;
missing documentation;
unsuitable material;
late delivery.

Need help comparing several random-packing quotations on the same engineering basis?

Prepare:

tower diameter · packed height · packing type/size/material · supplier datasheets · quoted unit basis · bulk density · wall thickness where applicable · quantity · Incoterm · freight data · documentation requirements

DAIER Tower Packing Engineering Assistant can support preliminary packing and quantity screening before detailed commercial and procurement review.