Name: Press Felt — Batt-on-Base Series — PAPTEX-PF-1500
Brand: PAPTEX
SKU: PAPTEX-PF-1500

Question 1

What paper grades is the Batt-on-Base Press Felt designed for?

PAPTEX Engineering Team · Accepted Answer

The Batt-on-Base Series covers the full paper grade range: tissue (12–40 g/m²), graphic paper (60–150 g/m²), fine paper (60–120 g/m²), packaging and kraft (80–300 g/m²), linerboard and testliner (100–300 g/m²), corrugated medium and fluting (100–180 g/m²), duplex board and white board (200–500 g/m²), newsprint (40–60 g/m²), and specialty grades including release paper and filter paper. Batt weight, needling density, and surface finish are customized per paper grade — a tissue-grade press felt uses finer batt fiber (3.3–6.7 dtex) on the sheet side for smooth surface finish, while a packaging-grade felt uses coarser batt (17–67 dtex) for wear resistance and higher void volume.

Question 2

What is the difference between single-layer, double-layer, and laminated base press felts?

PAPTEX Engineering Team · Accepted Answer

Single-layer base: one woven fabric layer. Lowest cost. Suitable for machines with nip pressure up to 200 kN/m (suction press, blind-drilled press). Weight range: 1,000–1,500 g/m². Double-layer base: two woven layers in a single weave. Higher void volume and better dimensional stability. Suitable for nip pressure up to 600 kN/m. Weight range: 1,300–1,800 g/m². Laminated base: two independent woven base fabrics needled together with batt fiber between and around them. Maximum void volume, highest dimensional stability, and longest service life. Suitable for shoe presses up to 1,200 kN/m. Weight range: 1,500–2,200 g/m². Our application engineer recommends the base construction based on your press configuration and nip pressures — this is included in every quotation.

Question 3

What batt fiber fineness should I specify for my paper grade?

PAPTEX Engineering Team · Accepted Answer

Batt fiber fineness determines sheet surface smoothness and water handling. General guidance: 3.3–6.7 dtex for tissue and fine paper (smoothest surface, lower void volume); 6.7–17 dtex for graphic paper and newsprint (balanced surface and water handling); 17–44 dtex for packaging, kraft, and linerboard (higher void volume, faster water removal); 44–67 dtex for heavy grades and machine-side batt layers (maximum wear resistance). Most press felts use layered batt: finer fiber on the sheet side for smoothness, coarser fiber on the machine side for durability. Our engineer specifies the batt fiber layout in every quotation.

Question 4

Can your press felt run on a shoe press?

PAPTEX Engineering Team · Accepted Answer

Yes. Our laminated base press felts are rated for shoe press operation at nip pressures up to 1,200 kN/m. We have supplied press felts for Valmet OptiPress and SymPress shoe presses, Voith NipcoFlex, and ANDRITZ PrimePress X. Key design features for shoe press applications: (a) laminated base fabric construction for maximum dimensional stability under extended nip residence time, (b) high batt weight (1,800–2,200 g/m²) for adequate void volume to handle the higher water load from shoe press dewatering, (c) PA66 batt fiber on the machine side for superior abrasion resistance against the shoe press belt, (d) reduced surface batt density to prevent sheet-side marking during extended nip dwell. Specify your shoe press model and nip pressure when requesting a quotation.

Question 5

What is void volume and why is it the most important press felt specification?

PAPTEX Engineering Team · Accepted Answer

Void volume is the percentage of felt volume available to absorb water from the paper sheet during the press nip. It is the single most important press felt specification because it directly determines dewatering capacity. Our felts achieve 35–55% void volume at 2 kPa reference pressure: 35–42% for tissue felts (finer batt, smoother surface), 42–50% for graphic and packaging felts, 48–55% for shoe press felts (laminated base). Higher void volume = more water absorbed per nip pass = higher sheet dryness exiting the press. Void volume is verified on every production felt at 12 measurement points across the width. A 1% increase in sheet dryness after the press section reduces dryer section steam consumption by approximately 4% — this is why press felt selection has the highest ROI of any paper machine clothing decision.

Question 6

How do I select the right press felt weight for my machine?

PAPTEX Engineering Team · Accepted Answer

Press felt weight (g/m²) is selected based on press configuration, nip pressure, and paper grade. General guidance: 1,000–1,300 g/m² for tissue and lightweight grades up to 80 g/m² (suction press, ≤ 200 kN/m nip); 1,300–1,600 g/m² for graphic and fine paper (suction/blind-drilled press, ≤ 400 kN/m nip); 1,500–1,900 g/m² for packaging and kraft (suction/blind-drilled press, ≤ 600 kN/m nip); 1,800–2,200 g/m² for shoe press applications and heavy linerboard grades (shoe press, up to 1,200 kN/m nip). Higher weight = more batt fiber = greater void volume and longer service life, but also higher cost and longer break-in. Our engineer calculates the optimal weight from your press parameters — included in every quotation.

Question 7

What information do you need to recommend a press felt?

PAPTEX Engineering Team · Accepted Answer

Required: machine brand, model, press configuration (suction press / shoe press / blind-drilled press), number of press nips, nip pressure range (kN/m), machine width (mm), design speed (m/min), paper grade(s), basis weight range (GSM), Uhle box vacuum level (kPa or mbar). Helpful but not required: current felt specifications (weight, caliper, base construction, batt fiber), felt conditioning system details (high-pressure shower pressure, chemical conditioning agents), felt roll diameters and condition, current pain points (low sheet dryness after press, short felt life, sheet marking, shadow marking, felt edge wear). Download our Machine Parameter Submission Form for the complete checklist.

Question 8

How long does a press felt typically last?

PAPTEX Engineering Team · Accepted Answer

Expected service life by application: tissue (1,200–2,200 m/min): 30–60 days — high nip frequency and fine batt fiber result in fastest wear. Graphic/fine paper (800–1,500 m/min): 45–90 days — surface wear and batt compaction are primary wear modes. Packaging/kraft (400–1,000 m/min): 60–180 days — longer life at lower speeds but higher contamination load from recycled fiber. Linerboard (300–800 m/min): 90–180 days — heaviest felts, longest life. Actual life depends on: nip pressure (higher = faster batt compaction), Uhle box vacuum level and maintenance, high-pressure shower condition (clogged nozzles cause uneven felt cleaning), felt conditioning chemical compatibility, and press roll condition (worn or grooved rolls accelerate felt wear). Our installation guide includes a felt condition monitoring schedule based on vacuum level trend and air permeability decline.

Question 9

What causes premature press felt failure?

PAPTEX Engineering Team · Accepted Answer

Seven common causes in the press section: (1) Batt compaction — the felt loses void volume over time due to repeated nip compression. This is the normal wear mechanism, but excessive nip pressure or insufficient felt conditioning accelerates it. (2) Filling — stickies, pitch, fillers, and fiber fines pack into the batt structure, blocking void volume. High-pressure shower and chemical conditioning are essential. (3) Chemical degradation — PA6/PA66 batt fiber is susceptible to hydrolysis below pH 4 and above pH 10. Monitor press section pH and avoid aggressive acid or caustic cleaning without chemical compatibility verification. (4) Uhle box wear — worn or misaligned Uhle box covers abrade the felt machine side, causing uneven thickness. (5) Seam failure — incorrect seam installation or excessive nip pressure at the seam. (6) Guide roll misalignment — causes uneven edge wear and felt drift. (7) Over-tensioning — press felts run at lower tension than dryer fabrics (typically 2–5 kN/m); excess tension causes permanent elongation and batt delamination. Our installation guide covers all seven with inspection criteria.

Question 10

What felt conditioning is required?

PAPTEX Engineering Team · Accepted Answer

Continuous conditioning during operation is critical for press felt performance and life. Three systems work together: (1) Uhle box (suction box) — removes water from the felt on the return run. Vacuum level: 25–60 kPa depending on felt weight and speed. Uhle box cover must be checked for wear at every felt change. (2) High-pressure needle shower — 20–40 bar, oscillating, on the felt return run before the Uhle box. Removes fillers and stickies from the batt structure. Nozzle spacing: 100–200 mm. Must use filtered water (≤ 50 μm) to prevent nozzle clogging. (3) Chemical conditioning — batch or continuous application of felt conditioner (alkaline for organic contaminants, acid for inorganic scale). Frequency: continuous low-concentration for high-contamination grades, batch every 4–8 hours for standard operation. Never use solvents containing phenol or chlorinated hydrocarbons. Our installation guide includes a complete felt conditioning setup checklist and chemical compatibility chart.

Question 11

What seam type do you recommend for press felts?

PAPTEX Engineering Team · Accepted Answer

Standard: pin seam — interlocking loops at each felt end connected by a pintle wire. Pin seam installation takes 45–90 minutes for press felts (batt thickness at the seam requires careful alignment). Seam strength retention ≥ 85% without reinforcement, ≥ 90% with seam reinforcement (recommended for shoe press applications). Loop seam: woven-in loops at both ends, connected by pintle — slightly higher strength, used for high-nip applications. Spiral seam: spiral coil inserted into felt ends — used for wide machines (> 7 m) or when frequent felt changes are prioritized. Seam reinforcement (additional batt needled over the seam zone) is recommended for: shoe presses, nip pressures above 600 kN/m, and positions where the seam passes through the nip. Seam type and reinforcement are confirmed during the quotation process.

Question 12

How do I measure my press section for a new felt order?

PAPTEX Engineering Team · Accepted Answer

We need: (1) Machine width — face width of the press rolls (mm). (2) Felt length — total loop length along the felt path through the press section (m). For press felts, length measurement must account for felt stretch during break-in — press felts elongate 1–3% in the first 24–48 hours of operation. We add the appropriate allowance based on your base fabric type and nip pressure. Length must be accurate within ± 0.5%. (3) Press configuration — number of nips, type of each nip (suction/shoe/blind-drilled), nip pressures, felt run drawing (if available). (4) Current felt specifications (if replacing). If you have a press section layout drawing, send it and we calculate dimensions. If not, our Machine Parameter Submission Form includes a measurement guide with press section diagrams.

Question 13

How is the press felt packed for international shipping?

PAPTEX Engineering Team · Accepted Answer

Each press felt is rolled on a 200 mm rigid PVC core with moisture-barrier polyethylene film — press felts must be kept completely dry during transport (moisture absorption changes caliper, weight, and void volume). Labeled with order number, machine position, dimensions, weight, felt type, seam type, running direction arrow, and "STORE HORIZONTAL — KEEP DRY — DO NOT COMPRESS" warning. Packed in reinforced plywood crate with desiccant packs. Crates are fumigated (ISPM 15 compliant). Standard crate weight: 120–400 kg depending on felt size (press felts are heavier than dryer fabrics). Storage before installation: horizontal, dry (≤ 60% RH), 15–30°C, away from direct sunlight (UV degrades PA6/PA66 batt fiber). Never stack crates — batt compression from stacking causes permanent caliper loss.

Question 14

How long does press felt installation take?

PAPTEX Engineering Team · Accepted Answer

Typical installation: 3–6 hours for a single press section position (from lifting to running tension). This includes: lifting felt onto machine (20–30 min — press felts are heavier than dryer fabrics), threading through press section — press rolls, Uhle boxes, felt rolls, guide rolls, stretch roll (60–120 min), seam installation (45–90 min for pin seam), tensioning and alignment (45–60 min), felt conditioning startup — verify Uhle box vacuum, high-pressure shower operation, and chemical conditioning system before running (15–30 min), break-in run at 70% nip pressure (6–8 hours before full-pressure operation). Full operating pressure after 24–36 hours of progressive increase. We provide a step-by-step installation checklist with felt path diagrams for suction press, shoe press, and combination press configurations.

Question 15

What is the minimum order quantity for a press felt?

PAPTEX Engineering Team · Accepted Answer

1 piece per press position. Each press felt is custom-manufactured to your exact machine dimensions, batt weight, base fabric type, and surface finish specification. No minimum beyond this. Single-position orders accepted. Multi-position orders benefit from consolidated packing, shipping, and quantity-based pricing. Most mills order 2–3 felts per position to ensure continuous operation during felt changes — we can hold inventory and ship on a scheduled release basis.

Question 16

What quality inspections does each press felt undergo?

PAPTEX Engineering Team · Accepted Answer

25+ inspection points per felt: raw material (batt fiber — fineness, tensile strength, elongation; base fabric yarn — diameter, tensile strength), in-process (batt weight distribution at 6 points across width, needling density verification, base fabric weave integrity, visual defects, seam loop integrity), post-production (weight ISO 9073-2 at 16 points across width, caliper at 16 points, density calculation, air permeability ISO 9237 at 16 points, water permeability ISO 11058 at 12 points, void volume measurement at 12 points, tensile strength ISO 13934-1 warp/weft, elongation at break, nip pressure simulation test, surface topography scan, seam strength test with actual pintle wire, dimensional check ± 0.5% of ordered length), pre-shipment (visual final inspection, packing integrity — moisture-barrier seal verified). Quality certificate and lot-specific test report shipped with every order.

Question 17

Can I visit the factory to inspect press felt production?

PAPTEX Engineering Team · Accepted Answer

Yes. Factory visits can be scheduled with 2 weeks notice. You will see: needling looms for batt-on-base production, TEXO (Sweden) high-speed looms for base fabric weaving, JAGER (Germany) automated heat-setting line, batt weight distribution inspection station, void volume and water permeability testing rig, nip pressure simulation equipment, surface topography scanner, quality inspection laboratory, R&D testing center, packing and shipping area. Address: Industrial Park, Shenqiu County, Zhoukou City, Henan Province, China. Nearest international airport: Zhengzhou Xinzheng (CGO), approximately 2.5 hours by car. Hotel and transfer arranged on request.

Question 18

What is your warranty policy for press felts?

PAPTEX Engineering Team · Accepted Answer

Standard: the felt is guaranteed to meet the agreed specifications (weight, caliper, void volume, air permeability, water permeability, tensile strength, dimensional accuracy) at the time of shipment. If a felt fails before expected service life, we analyze the returned sample (free) and provide a failure analysis report within 10 business days. Manufacturing defect → replacement felt at no charge or pro-rated credit. Operational failure (batt compaction from over-pressure, chemical damage, Uhle box abrasion, insufficient conditioning) → we provide recommendations to prevent recurrence. Our press felt failure analysis reports frequently identify root causes mills were unaware of — clogged shower nozzles, incorrect Uhle box vacuum settings, and incompatible felt conditioning chemicals being the most common.

Question 19

Can your press felt match the specifications of my current supplier?

PAPTEX Engineering Team · Accepted Answer

Yes. Send us a sample of your current felt (A4 size) or its full specifications (weight, caliper, base fabric construction, batt fiber composition, air permeability, water permeability, void volume). Our lab analyzes the sample within 5 business days at no charge and provides: (a) complete reverse-engineering report with all measured parameters, including batt fiber cross-section analysis, (b) our proposed felt design that matches or exceeds each parameter, (c) competitive quotation. Most mills achieve equivalent or improved sheet dryness and felt life on the first trial felt. This is our standard new-customer process.

Question 20

What are your payment terms?

PAPTEX Engineering Team · Accepted Answer

Standard: 30% T/T deposit with order confirmation, 70% before shipment. L/C at sight: available for orders above USD 10,000. Long-term customers (> 3 orders): flexible payment schedule available. All prices quoted FOB Shanghai or CIF destination. Pro forma invoice issued within 24 hours of order confirmation.

Question 21

How does your press felt compare to Voith OEM press felts?

PAPTEX Engineering Team · Accepted Answer

Voith: OEM-specified press felt, designed and tested specifically for Voith press sections (NipcoFlex, DuoCentri). PAPTEX: independent aftermarket alternative. Same PA6/PA66 batt fiber, same PET base fabric materials, same ISO test standards (ISO 9073-2, ISO 9237, ISO 11058, ISO 13934-1). Key operational differences: (a) 30–50% lower cost than OEM felt, (b) we provide void volume, water permeability, and nip simulation data in every quotation — not all OEMs provide this level of detail, (c) direct engineer access — you discuss press felt design with the engineer who designs it, not a sales representative, (d) 15–25 day delivery. Mills that switch from Voith OEM typically run a single trial felt first — we reverse-engineer your current felt and match or improve each parameter. Sheet dryness after press is measured and compared.

Brand	Compatible Models	Typical Width	Typical Speed
Valmet	SymPress, OptiPress, Press Section	3,500 – 8,600 mm	up to 2,200 m/min
Voith	NipcoFlex, DuoCentri, QualiPress	3,000 – 7,800 mm	up to 2,000 m/min
ANDRITZ	PrimePress, PrimePress X	3,000 – 8,000 mm	up to 1,800 m/min
Bellmer	TurboPress, Press Section Standard	2,500 – 5,500 mm	up to 1,200 m/min
Toscotec	TT Press	2,800 – 6,000 mm	up to 2,000 m/min
A.Celli	AC-Press Series	2,500 – 5,600 mm	up to 1,500 m/min
Recard	Press Section	2,200 – 4,800 mm	up to 1,200 m/min
Over Meccanica	OM-Press	2,400 – 5,200 mm	up to 1,000 m/min

Material	Batt fiber: 100% Polyamide (PA6/PA66). Base fabric: 100% Polyester (PET) or PET/PA6 hybrid. Batt-to-base ratio: 45:55 to 65:35 (application-dependent).
Construction	Needle-punched batt-on-base. Woven base fabric (single-layer / double-layer / laminated) with batt fiber needled from one or both sides. Batt weight and needling density adjusted per application.
Weight	1,000 – 2,200 g/m² (application-dependent; higher weight = greater void volume = more water removal per nip)
Weight Tolerance	± 3% across full width
Caliper	2.0 – 5.5 mm (measured at 2 kPa, ISO 9073-2)
Caliper Tolerance	± 0.08 mm across full width
Density	0.30 – 0.50 g/cm³ (lower density = higher void volume = better water handling)
Air Permeability	15 – 120 CFM (at 125 Pa, ISO 9237). Press felts have significantly lower air permeability than dryer fabrics — water removal is by mechanical pressing, not air flow.

Press Felt — Batt-on-Base Series

Paper Grades & Machine Conditions

Paper Grades

Machine Types

Operating Range

Compatible Paper Machine Brands & Models

Complete Technical Parameters

Differentiation & Selection Guide

vs Other PAPTEX Models

vs Competitor Alternatives

Technical Documents

Press Felt — Technical Datasheet

Press Felt — Installation & Conditioning Guide

Machine Parameter Submission Form

PAPTEX Press Felt Batt-on-Base Series — Technical Datasheet

PAPTEX Press Felt — Installation & Conditioning Guide

PAPTEX Press Felt — Machine Parameter Submission Form

Procurement Questions

Request Press Felt Recommendation

Press Felt Working Principle